Part 5: Fire and Safety – Measures and Features

RULES FOR BUILDING AND CLASSING

MOBILE OFFSHORE DRILLING UNITS

2018

PART 5
FIRE AND SAFETY – MEASURES AND FEATURES

American Bureau of Shipping

Incorporated by Act of Legislature of
the State of New York 1862

 2017 American Bureau of Shipping. All rights reserved.

ABS Plaza
16855 Northchase Drive
Houston, TX 77060 USA
R u l e C h a n g e N o t i c e ( 2 0 1 8 )

Rule Change Notice (2018)

The effective date of each technical change since 1993 is shown in parenthesis at the end of the
subsection/paragraph titles within the text of each Part. Unless a particular date and month are shown, the
years in parentheses refer to the following effective dates:
(2000) and after 1 January 2000 (and subsequent years) (1996) 9 May 1996
(1999) 12 May 1999 (1995) 15 May 1995
(1998) 13 May 1998 (1994) 9 May 1994
(1997) 19 May 1997 (1993) 11 May 1993

Listing by Effective Dates of Changes from the 2017 Rules

EFFECTIVE DATE 1 January 2018 – shown as (2018)
(based on the contract date for new construction between builder and Owner)
Part/Para. No. Title/Subject Status/Remarks
5-1-1/3.17ii) <No Title> To align the requirements with 9.2.9 of the IMO MODU Code.
5-1-1/33 <No Title> To align the requirements with 9.3.17 of the IMO MODU Code.
5-1-1/Figure 1 Pipes Penetrating “A” Class Divisions To add PVC material, in line with SOLAS Chapter II-2 Regulation 9.3.
5-1-1/Figure 2 Pipes Penetrating “B” Class Divisions To add PVC material, in line with SOLAS Chapter II-2 Regulation 9.3.
5-1-1/Figure 4 Ventilation Ducts Penetrating “B” To align the requirements with 9.3.17 of the IMO MODU Code.
Class Divisions
5-2-3/1.3.1 Fixed Fire Extinguishing Systems on To require that the closed moonpool area is also to be protected for
Drilling Area and Temporary Well firefighting at the same level as the drillfloor.
Test Area, and Moonpool Area
5-2-3/3.1.2 Design To provide a clear instruction for the pressure rating of the distribution
pipe.
5-2-3/9.1 General To specify provisions for the use of aluminum helidecks.
5-2-4/Table 2 Hand Portable Fire Extinguishers and To align the requirements with Table 9-3 of IMO MODU Code 2009
Semi-portable Fire-Extinguishing (refer to MSC.1/Circ.1275).
Systems
5-2-5/1.1.2 Machinery Spaces To align the requirements with ABS practice.
5-2-5/5.3 Alarms To clarify the requirements and to specify that “the high level alarm”
should immediately activate the toxic alarm without waiting for
crew’s acknowledge at the main control panel.
5-3-1/3 Means of Access and Egress To clarify the requirements for aluminum helideck escape stairs and
intermediate platforms.
5-3-1/9.9 Floor Plating in Machinery Spaces of To specify that FRP is not allowed in machinery spaces of Category
Category A A.

ii ABS RULES FOR BUILDING AND CLASSING MOBILE OFFSHORE DRILLING UNITS . 2018
PART Table of Contents

5
Fire and Safety – Measures and Features

CONTENTS
CHAPTER 1 Passive Fire Protection.......................................................................... 1
Section 1 General .................................................................................. 2

CHAPTER 2 Active Fire Protection Systems and Equipment ................................ 15

Section 1 General ................................................................................ 17
Section 2 Fixed Fire Fighting Systems ................................................ 19
Section 3 Additional Fixed Fire Fighting Systems ............................... 23
Section 4 Portable Fire Fighting Systems ............................................ 32
Section 5 Fire and Gas Detection ........................................................ 36

CHAPTER 3 Outfitting ............................................................................................... 39

Section 1 General ................................................................................ 41

Appendix 1 Fiber Reinforced Plastic (FRP) Gratings ............................. 46

Appendix 2 Fiber Reinforced Plastic (FRP) Guard Railings ................... 49

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This Page Intentionally Left Blank
PART Chapter 1: Passive Fire Protection

5
CHAPTER 1 Passive Fire Protection

CONTENTS
SECTION 1 General .................................................................................................... 2
1 General ............................................................................................... 2
1.1 Administration Review ..................................................................... 2
1.3 ABS Review .................................................................................... 2
1.5 Materials Containing Asbestos ........................................................ 2
1.7 Alternative Design and Arrangements ............................................. 2
3 Structural Fire Protection .................................................................... 2
5 Protection of Accommodation Spaces, Service Spaces and
Control Stations .................................................................................. 7

TABLE 1 Fire Integrity of Bulkheads Separating Adjacent Spaces ......... 3

TABLE 2 Fire Integrity of Decks Separating Adjacent Spaces ................ 4

FIGURE 1 Pipes Penetrating “A” Class Divisions ...................................... 6

FIGURE 2 Pipes Penetrating “B” Class Divisions ...................................... 7
FIGURE 3 Ventilation Ducts Penetrating “A” Class Divisions .................. 11
FIGURE 4 Ventilation Ducts Penetrating “B” Class Divisions .................. 13

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PART Section 1: General

5
CHAPTER 1 Passive Fire Protection

SECTION 1 General

1 General (1993)
All mobile offshore drilling units are to meet the requirements of this Chapter with regard to structural fire
protection, protection of accommodation spaces, service spaces and control stations.

1.1 Administration Review

When a Mobile Offshore Drilling Unit Safety Certificate is issued to a MODU by an Administration or its
agent other than ABS, such certificate will be accepted as evidence that the unit is in accordance with the
requirements of this Chapter.

1.3 ABS Review

In all other cases, the required information and plans are to be submitted to ABS for review.

1.5 Materials Containing Asbestos (2011)

Installation of materials, which contain asbestos, is prohibited.

1.7 Alternative Design and Arrangements (2012)

When fire safety design or arrangements deviate from the prescriptive provisions of the Rules, including
innovative means of passive fire protection, an engineering analysis, evaluation and approval of the alternative
design and arrangements has to be carried out in accordance with SOLAS Regulation II-2/17 and ABS
Guidance Notes on Alternative Design and Arrangements for Fire Safety.

3 Structural Fire Protection (1993)

3.1 Construction Materials

These requirements apply to mobile offshore drilling units with their hulls, superstructures, structural
bulkheads, decks and deckhouses constructed of steel.

3.3 Alternate Materials

Construction of other materials may be accepted, provided that they provide an equivalent standard of safety.

3.5 Details, Materials and Methods of Construction (2017)

Structural fire protection details, materials and methods of construction are to be in accordance with the
International Code for Application of Fire Test Procedures (Resolution MSC.307(88)) (FTP Code), as
applicable, and SOLAS Regulations II-2/5.3 and II-2/6, as applied to cargo ships.

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3.7 Fire Integrity of Bulkheads and Decks (2017)

In addition to complying with the specific provisions for fire integrity of bulkheads and decks in this
Section and in 5-1-1/5, the minimum fire integrity of bulkheads and decks is to be as prescribed in 5 1-
1/Table 1 and 5-1-1/Table 2. These requirements apply to all normally occupied permanent structures,
temporarily installed modular building and portable accommodation modules. The exterior boundary of
normally occupied superstructures, deckhouses enclosing accommodations and modular building,
including any overhanging decks supporting such accommodations, are to be an “H-60” Class boundary
for the whole of the portion which faces and is within 30 m (98 ft) of the center of the rotary table. The 30
m (98 ft) is measured with the rotary at its closest drilling position to the normally occupied permanent
structures, modular building, and accommodation. If worst fire risk analysis indicates the radiant heat flux
of exterior boundaries of such buildings are not exceeding 100 kW/m2, “A-60” standard can be considered.
Notes:
1 Class “A” or Class “B” divisions and their associated insulation index are as defined in SOLAS
Regulation II-2/3.2 or 3.4, respectively.
2 H-class divisions are fire barriers that have been tested to a fire test using the hydrocarbon time-
temperature furnace heating curve as defined in ISO 834/1363-2 or ASTM E 1529. They are rated
similarly to "A" class divisions as defined in SOLAS regulation II-2/3.2.

TABLE 1
Fire Integrity of Bulkheads Separating Adjacent Spaces (2017)
Spaces (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11)
Control Stations (1) A-0 (4) A-0 A-60 A-0 A-15 A-60 A-15 A-60 (5) A-60 * A-0
Corridors (2) C B-0 B-0 B-0 A-60 A-0 A-0 (5) A-0 * B-0
A-0 (2)
Accommodation Spaces (3) C B-0 B-0 A-60 A-0 A-0 (5) A-0 * C
A-0 (2)
Stairways (4) B-0 B-0 A-60 A-0 A-0 (5) A-0 * B-0
A-0 (2) A-0 (2) A-0 (2)
Service Spaces (low risk) (5) C A-60 A-0 A-0 A-0 * B-0
Machinery Spaces of Category A (6) *Note 1 A-0 (1) A-60 A-60 * A-0
Other Machinery Spaces (7) A-0 (1,3) A-0 A-0 * A-0
Hazardous Areas (8) — A-0 — A-0
Service Spaces (high risk) (9) A-0 (3) * A-0
Open Decks (10) — *
Sanitary and Similar Spaces (11) C

Notes: To be applied to both 5-1-1/Table 1 and 5-1-1/Table 2, as appropriate.

1 Where the space contains an emergency power source or components of an emergency power source that adjoins a
space containing a unit’s service generator or the components of a unit’s service generator, the boundary bulkhead
or deck between those spaces is to be an “A-60” Class division.
2 For clarification as to which note applies, see paragraphs 5-1-1/5.5 and 5-1-1/5.9.
3 (2012) Where spaces are of the same numerical category and superscript (3) appears, a bulkhead or deck of the
rating shown in the tables is only required when the adjacent spaces are for a different purpose, e.g., in category
(9), a galley next to a galley does not require a bulkhead, but a galley next to a paint room requires an “A-0”
bulkhead. Where a bulkhead is installed between two spaces of the same numerical category which are for the
same purpose, the separating bulkhead is to be made of non-combustible material (except for spaces separated for
redundancy in units with DPS-3 notation, where the separating bulkhead is to be “A-60” rating).
4 Bulkheads separating the navigation bridge, chart room and radio from each other may be “B-0” rating.
5 (2017) An engineering evaluation is to be conducted in accordance with 5-1-1/5.1. In no case should the bulkhead
or deck rating be less than the value indicated in the table. Where it is shown that normally occupied spaces may
be exposed to a radiant heat flux in excess of 100 kw/m2, the bulkhead or deck should be constructed to at least an
“H-60” standard.
* When an asterisk appears in the tables, the division is required to be of steel or equivalent material but is not
required to be of “A” Class standard. However, where a deck is penetrated for the passage of electric cables, pipes
and vent ducts, such penetrations should be made tight to prevent the passage of flame and smoke.

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TABLE 2
Fire Integrity of Decks Separating Adjacent Spaces (2012)
Spaces ↓ Space → (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11)
Below Above
Control Stations (1) A-0 A-0 A-0 A-0 A-0 A-60 A-0 A-0 (5) A-0 * A-0
Corridors (2) A-0 * * A-0 * A-60 A-0 A-0 (5) A-0 * *
Accommodation Spaces (3) A-60 A-0 * A-0 * A-60 A-0 A-0 (5) A-0 * *
Stairways (4) A-0 A-0 A-0 * A-0 A-60 A-0 A-0 (5) A-0 * A-0
Service Spaces (low risk) (5) A-15 A-0 A-0 A-0 * A-60 A-0 A-0 A-0 * A-0
Machinery Spaces of Category A (6) A-60 A-60 A-60 A-60 A-60 *Note 1 A-60 A-60 A-60 * A-0
Other Machinery Spaces (7) A-15 A-0 A-0 A-0 A-0 A-0 (1) *Note 1 A-0 A-0 * A-0
(5) (5) (5) (5)
Hazardous Areas (8) A-60 A-0 A-0 A-0 A-0 A-60 A-0 — A-0 — A-0
Service Spaces (high risk) (9) A-60 A-0 A-0 A-0 A-0 A-60 A-0 A-0 A-0 (3) * A-0
Open Decks (10) * * * * * * * — * — *
Sanitary and Similar Spaces (11) A-0 A-0 * A-0 * A-0 A-0 A-0 A-0 * *

Notes: See Notes under 5-1-1/Table 1.

3.9 Application of Tables

The following requirements govern application of the tables:
3.9.1
5-1-1/Table 1 and 5-1-1/Table 2 apply, respectively, to the bulkheads and decks separating adjacent
spaces.
3.9.2
For determining the appropriate fire integrity standards to be applied to divisions between adjacent
spaces, such spaces are classified according to their fire risk, as shown in Categories (1) to (11)
below. The title of each category is intended to be typical rather than restrictive. The number in
parenthesis preceding each category refers to the applicable column or row in the tables:
(1) (2017) Control Stations are those spaces in which
• Radio or main navigation equipment is located, or
• Where the fire monitoring or fire control equipment is centralized, or
• Where the dynamic positioning system controls or activation of fire-extinguishing
systems serving various location are situated, or
• Centralized ballast control station in column-stabilized units.
For the purpose of the application of 5-1-1/Table 1 and 5-1-1/Table 2, fixed gas fire-
extinguishing system storage rooms are to be treated as control stations.
(2) Corridors means corridors and lobbies.
(3) Accommodation Spaces are those used for public spaces, cabins, offices, hospitals, cinemas,
game and hobby rooms and similar spaces. Public spaces are those portions of the
accommodation which are used for meeting halls, dining rooms, lounges and similar
permanently enclosed spaces.
(4) Stairways are interior stairways, lifts and escalators (other than those wholly contained
within the machinery spaces) and enclosures thereto. In this connection, a stairway which
is enclosed only at one level is regarded as part of the space from which it is not separated
by a fire door.
(5) (1999) Services Spaces (low risk) are lockers, storerooms and working spaces in which
flammable materials are not stored; drying rooms, laundries; refrigerating, ventilation and
air-conditioning machinery spaces with motors having an aggregate capacity not greater
than 7.5 kW (10 hp).

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(6) Machinery Spaces of Category A are all spaces which contain internal combustion type
machinery used either:
• For main propulsion or
• For other purposes where such machinery has in the aggregate a total power of not less
than 375 kW (500 hp) or which contain any oil-fired boiler or oil fuel unit; and trunks
to such spaces.
(7) (1999) Other Machinery Spaces are those spaces, including trunks to such spaces, containing
propulsion machinery, boilers, oil fuel units, steam and internal combustion engines,
generators and major electrical machinery (SCR, MCC and switchgear); oil filling station;
refrigerating, ventilation and air-conditioning machinery with motors having an aggregate
capacity greater than 7.5 kW (10 hp); and similar spaces, but are not machinery spaces of
Category A.
(8) Hazardous Areas are all those areas where, due to the possible presence of a flammable
atmosphere arising from the drilling operation, the use without proper consideration of
machinery or electrical equipment may lead to fire hazard or explosion. See Section 4-3-6.
(9) Services Spaces (high risk) are lockers, storerooms and working spaces in which flammable
materials are stored, galleys, pantries containing cooking appliances, paint rooms and
workshops other than those forming part of the machinery space.
(10) Open Decks are open deck spaces excluding hazardous spaces.
(11) Sanitary and Similar Spaces are communal sanitary facilities such as showers, baths,
lavatories, etc., and isolated pantries containing no cooking appliances. Sanitary facilities
which serve a space and with access only from that space shall be considered a portion of
the space in which they are located.

3.11
Continuous “B” class ceilings or linings in association with the relevant decks or bulkheads will be accepted
as contributing to the required insulation and integrity of a division.

3.13 (2012)
Structural fire protection details are to avoid the risk of heat transmission at intersections and terminal
points of required thermal barriers. The insulation of a deck or bulkhead is to be carried past the penetration,
intersection or terminal point for a distance of at least 450 mm in the case of steel and aluminum structures.
If a space is divided with a deck or a bulkhead of “A” class standard having insulation of different values,
the insulation with the higher value is to continue on the deck or bulkhead with the insulation of the lesser
value for a distance of at least 450 mm.

3.15
Windows and sidescuttles, with the exception of navigation bridge windows, are to be of the non-opening
type. Navigation bridge windows may be of the opening type, provided the design of such windows permits
rapid closure. Windows and sidescuttles outside of hazardous areas may be of the opening type.

3.17 (2011)
i) The fire resistance of doors are to be equivalent to that of the division in which they are fitted.
ii) (2018) External doors in superstructures and deckhouses are to be at least “A-0” class standard and
be self-closing, where practicable. Where external doors in bulkheads of superstructures and deckhouses
are required to be watertight, they need not be self-closing; however, they are to be fitted with a
notice on both sides of the door stating that the doors are to be kept closed unless an adjacent self-
closing fire rated door is provided.
iii) (2017) Watertight doors in a watertight division fitted below the bulkhead deck need not be tested
to the Fire Test Procedure Code (Resolution MSC.307(88)) requirements for the fire rating of the
division in which the door is fitted. The bulkhead deck is the highest deck to which watertight
bulkheads extend and are made effective.

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iv) (2017) Watertight doors fitted in a fire rated division above the bulkhead deck are to be tested to
the Fire Test Procedure Code (Resolution MSC.307(88)) requirements for the fire rating of the
division in which the door is fitted and, if applicable, the watertight door are to meet the self-closing
requirements. Watertight doors are to meet the requirements of ii), when applicable.
v) Where a watertight door is located adjacent to a fire door, both doors are to be capable of independent
operation, remotely if required and from both sides of each door.
vi) (2012) Self-closing doors in fire rated bulkheads are not to be fitted with hold-back hooks. However,
hold-back arrangements incorporating remote release fittings of the fail-safe type may be utilized.

3.19 (1999)
Arrangements are to be made to ensure that the fire resistance is not impaired when
i) “A” and “B” class divisions are penetrated for the passage of electrical cables, pipes, trunks, ducts, etc.
ii) “A” class divisions are penetrated for girders, beams or other structural members, or
iii) “B” class divisions are penetrated for the fitting of ventilation terminals, lighting fixtures and similar
devices.

3.21 (2011)
Where pipes penetrate “A” class divisions, such penetrations are to be tested in accordance with the Fire
Test Procedures Code. If the penetration is constructed of steel or fitted with a steel sleeve at least 3 mm
(0.12 in.) thick and at least 900 mm (35.4 in.) long (preferably 450 mm (17.7 in.) on each side of the
division) and provided with fire insulation having the same length and fire integrity as the division, testing
is not required. See 5-1-1/Figure 1.
Uninsulated metallic pipes penetrating “A” class divisions are to be of materials having a melting
temperature which exceeds 950°C (1742°F).

FIGURE 1
Pipes Penetrating “A” Class Divisions (2018)
“A” Class Division (Pipe material: Steel, Copper, Al-alloy, PVC)
(1) “A-0” Class (2) “A-15”, “A-30”, “A-60” Class
steel penetration piece
Division t mm  Division

L L L L
pipe

steel sleeve
Division t mm  Division

L L L L
pipe

Lmin mm (in.) min mm (in.) t mm (in.)

All sizes 450 (17.7) 450 (17.7) 3.0 (0.12)

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3.23 (2011)
Where pipes penetrate “B” class divisions, such penetrations are to be tested in accordance with the Fire
Test Procedures Code. Testing is not required however if:
i) Pipes having diameters greater than or equal to 150 mm (5.91 in.) penetrating “B” class divisions
are steel or lined with steel sleeves at least 1.8 mm thick and at least 900 mm (35.4 in.) long
(preferably 450 mm (17.7 in.) on each side of the division). See 5-1-1/Figure 2.
ii) Pipes having diameters less than 150 mm (5.91 in.) are to be steel or lined with steel sleeves at
least 1.8 mm thick and at least 600 mm (23.6 in.) long (preferably 300 mm (11.81 in.) on each side
of division). See 5-1-1/Figure 2.
iii) Pipes other than steel or copper are connected to the ends of the sleeve defined in i) and ii) by
flanges or couplings; or the clearance between the sleeve and the pipe is not to exceed 2.5 mm; or
any clearance between pipe and sleeve is to be made tight by means of non-combustible or other
suitable material. Uninsulated metallic pipes (including copper) penetrating “B” class divisions
have a melting temperature which exceeds 850°C (1562°F).

FIGURE 2
Pipes Penetrating “B” Class Divisions (2018)
“B” Class Division
(1) Steel Pipe, Copper (1) (2) Al-alloy Pipe, PVC Pipe

Division

Gap to be kept minimum

(max. 2.5 mm (0.10 in.)

Steel sleeve or L L
t ≥ 1.8 mm (0.07 in.) penetration piece
t ≥ 1.8 mm (0.07 in.)

L = 450 mm (17.7 in.) for diameters of 150 mm (5.9 in.) or more

L = 300 mm (11.8 in.) for diameters of less than 150 mm (5.9 in.)
1 Copper penetrations are required to have a melting temperature which exceeds 850°C (1562°F).

5 Protection of Accommodation Spaces, Service Spaces and Control

Stations (1993)

5.1 (2016)
In addition to the requirements of 5-1-1/3.7, accommodation spaces, service spaces and control stations, in
general, are not to be located adjacent to hazardous areas. However, where this is not practicable, an
engineering evaluation is to be performed to verify that the level of fire protection and blast resistance of
the bulkheads and decks separating these spaces from the hazardous areas are adequate for the likely
hazard. A Risk Analysis is to be submitted for review addressing the possible fire and explosion hazardous
and identifying the worst foreseen hazards (fire and/or explosion). Depending on the type of hazard as
determined from the risk analysis a Fire Load Analysis and/or a Blast Analysis are to be submitted for
review with the mitigation measures (where needed) to allow safe operations.

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5.1.1
Where a blast analysis is needed based on the risk analysis, the analysis is to show for the worst
foreseen blast scenario that the space is protected.
i) Plastic deformation of the spaces’ structure is acceptable.
ii) Attention is to be paid to penetrations through the bulkheads such as doors and HVAC
openings.
iii) No penetration of the blast overpressure is allowed to enter the space through the division
panels. Overpressures of 0.07 bar (0.07 kgf/cm2; 1 psi) are allowable through penetrations
of the division; the point of measurement of the overpressure is where the overpressure
enters the open air of the space (i.e., the vent duct grill). Unmanned service spaces can
have higher overpressures through penetrations if justified.
iv) Windows subject to blast overpressures are to remain intact.
For simplified blast analysis, the overpressure values in API RP 2FB, Table C.6.4.1 may be used.
Justification for the level of congestion (congested/non-congested) that an area has must be
provided. Justification on the duration of the assumed blast impulse must be provided.
5.1.2
Where a fire analysis is needed based on the risk analysis, the analysis is to show that for the worst
foreseen fire scenario the following internal temperature and structural criteria:
i) The temperature of the protected side of the fire division (bulkhead or deck) does not
increase more than:
a) 139°C (282°F) on average above ambient temperature for the time period of the
event, but need not exceed 120 minutes and
b) 180°C (356°F) at any point above ambient temperature for the time period of the
event, but need not exceed 120 minutes
ii) The structure of the division (bulkhead or deck) is to remain intact with the main structure
of the vessel, and is to maintain its structural integrity for two (2) hours. Structural Integrity
means that the structure will not fall under its own weight, nor will it crumble or break
upon normal contact after exposure to a fire lasting two (2) hours.
Buildings with bulkheads and decks that are H-120 Class fire divisions facing hazardous areas
would not need a fire analysis; thus, only blast loads would need to be considered. Division sides
not facing the fire hazard but which share a common edge with a division that faces the hazard are
to have a 3 meter extension of the H-120 Class fire rated division. See Chapter 2, Section 1 of the
ABS Rules for Building and Classing Facilities on Offshore Installations (Facilities Rules) for the
definition of “H-120” divisions.
5.1.3 (2017)
Where it is shown that normally occupied spaces may be exposed to a radiant heat flux in excess
of 100 kw/m2, the bulkhead or deck should be constructed to at least an “H-60” standard.

5.3 (2012)
All bulkheads that are to be “A” class divisions are to extend from deck to deck and to the deckhouse side
or other boundaries.

5.5 (2012)
All bulkheads forming “B” Class divisions are to extend from deck to deck and to the deckhouse side or
other boundaries, unless continuous “B” Class ceilings and/or linings are fitted on both sides of the bulkhead, in
which case the bulkhead may terminate at the continuous ceiling or lining. In corridor bulkheads, ventilation
openings are to be provided only in and under the doors of cabins, public spaces, offices and sanitary spaces.
The openings are to be provided only in the lower half of the door. Any such opening in or under a door is to

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have a total net opening no larger than 0.05 m2 (0.54 ft2) and is to be fitted with a noncombustible grill. Such
openings are not to be provided in a door in a division forming a stairway enclosure.

5.7 (2012)
Stairs are to be constructed of steel or other equivalent material which would not be rendered ineffective
by heat.

5.9 (2012)
Stairways which penetrate only a single deck are to be protected at least at one level by “A” or “B” Class
divisions and self-closing doors so as to limit the rapid spread of fire from one deck to another. Elevator
trunks are to be protected by “A” Class divisions. Stairways and elevator trunks which penetrate more than
a single deck are to be surrounded by “A” Class divisions and protected by “A” Class self-closing doors at
all levels.

5.11 (2012)
Air spaces enclosed behind ceilings, paneling or linings are to be divided by close fitting draft stops spaced
not more than 14 m (46 ft) apart. In the vertical direction, such enclosed air spaces, including those behind
linings of stairways, trunks, etc., are to be closed at each deck.

5.13 (2012)
Except for insulation in refrigerated compartments, insulating materials, including pipe and vent duct lagging,
ceilings, linings and bulkheads are to be of non-combustible material. Vapor barriers and adhesive used in
conjunction with insulation, as well as insulation of pipe fittings for cold service systems need not be
noncombustible, but they should be kept to a minimum and their exposed surfaces are to have low flame
spread characteristics. In spaces where penetration of oil products is possible, the insulation surfaces are to
be impervious to oil or oil vapors.

5.15
The framing, including grounds and the joint pieces of bulkheads, linings, ceilings and draft stops are to be
of noncombustible material.

5.17
In accommodation and service spaces and control stations, the following surfaces are to have low flame-
spread characteristics:
i) All exposed surfaces in corridors and stairway enclosures;
ii) Surface in concealed or inaccessible spaces;
iii) Exposed surfaces of ceilings.

5.19 (2012)
Bulkheads, linings and ceilings may have combustible veneers, provided that the thickness of such veneers
does not exceed 2.5 mm (0.10 in.) within any space other than corridors, stairway enclosures and control
stations where the thickness is not to exceed 1.5 mm (0.06 in.). Combustible materials used on these surfaces
are to have a calorific value not exceeding 45 MJ/m2 of the area for the thickness used.

5.21 (2012)
Primary deck coverings, if applied, within accommodation and service spaces and control stations, are to be
of approved materials which will not readily ignite, this being determined in accordance with the FTP Code.

5.23 (2012)
Paints, varnishes and other finishes used on exposed interior surfaces are not to be capable of producing
excessive quantities of smoke and toxic products, this being determined in accordance with the FTP Code.

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Part 5 Fire and Safety – Measures and Features
Chapter 1 Passive Fire Protection
Section 1 General 5-1-1

5.25
Ventilation ducts are to be of a noncombustible material, unless they are no more than 2 m (6.6 ft) long and
have a cross-sectional area no more than 0.02 m2 (0.22 ft2) and:
i) Are of a material which has a low fire risk
ii) Are used only at the end of the ventilation device
iii) Are not situated less than 600 mm (23.5 in.), measured along the duct, from its penetration of any
“A” or “B” class division, including continuous “B” class ceilings

5.27 (2012)
Ventilation ducts having an internal cross-sectional area greater than 0.02 m2 (0.22 ft2) penetrating “A”
class divisions are to be steel or lined with a steel sheet sleeve that:
i) Are at least 3 mm (0.118 in.) thick and at least 900 mm (35.4 in.) long (preferably 450 mm (17.7 in.) on
each side of the division), provided with fire insulation having the same fire integrity as the division;
and
ii) Those exceeding 0.075 m2 (0.81 ft2), except those serving hazardous areas, are to also have automatic
fire damper capable of being closed manually from both sides of the bulkhead or deck and with a
position indicator which shows whether the damper is open or closed. The fire dampers are not
required where ducts pass through spaces surrounded by “A” class divisions, without serving those
spaces, provided those ducts have the same fire integrity as the divisions which they penetrate.
iii) For control stations, where the duct line serves other category spaces, a fire damper is to be provided
regardless of size.
iv) (2017) Where a fire damper is located within a ventilation coaming and cannot be examined by
other means, an inspection port or opening at least 150 mm (6 in.) in diameter is to be provided in
the coaming to facilitate survey of the damper without disassembling the coaming or the ventilator.
The closure provided for the inspection port or opening is to maintain structural integrity of the
coaming and, if appropriate, the fire integrity of the coaming.
Ventilation ducts less than or equal to 0.02 m2 (0.22 ft2) penetrating “A” class divisions are to be steel or
lined with steel sheet sleeves that are at least 3 mm (0.12 in.) thick and at least 200 mm (7.88 in.) long
(preferably 100 mm (3.93 in.) on each side of bulkhead or, in the case of the deck, wholly laid on the lower
side of the deck pierced) and provided with fire insulation having the same fire integrity as the division.
See 5-1-1/Figure 3.

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Chapter 1 Passive Fire Protection
Section 1 General 5-1-1

FIGURE 3
Ventilation Ducts Penetrating “A” Class Divisions (2012)
(1) “A-0” Class (2) “A-15”, “A-30”, “A-60” Class

steel sleeve
Division t mm  Division

L L L L
steel duct

L mm (in.)  mm (in.) t mm (in.) Automatic Damper**

S > 750 cm2 450 (17.7) 450 (17.7) 3.0 (0.12) Required *
750 cm2 ≥ S > 200 cm2 450 (17.7) 450 (17.7) 3.0 (0.12) Not required
200 cm2 ≥ S min. 100 (3.94) min. 100 (3.94) 3.0 (0.12) Not required
* Not required if duct passes through spaces surrounded by "A" class divisions, without serving those spaces, provided
the duct has the same fire integrity as the divisions it pierces.
** Automatic fire damper capable of being closed manually from both sides of the division.
S = Sectional area of duct

5.29 (2016)
Ventilation systems include the air handling units and/or fans, associated supply, return and/or exhaust
ducting, and miscellaneous components.
Ventilation systems for machinery spaces of category A, galleys, and hazardous areas are to be separated
from each other and from the ventilation systems serving other spaces, (see also 4-3-6/9.1).
Ducts serving hazardous areas are to not pass through accommodation spaces, service spaces, or control
spaces.
Ducts provided for the ventilation of machinery spaces of category A and galleys are not to pass through
accommodation spaces, control stations or service spaces unless:
i) Constructed of steel at least 3 mm (0.12 in.) thick for ducts 300 mm (12 in.) wide or less, and at
least 5 mm (0.20 in.) for ducts 760 mm (30 in.) wide and over.
The minimum thickness is to be interpolated for widths or diameters between 300 and 760 mm
(12 and 30 in.);
ii) Fitted with an automatic fire damper close to the boundaries penetrated;
iii) Insulated to “A-60” standard from the machinery space or galleys to a point at least 5 m (16.4 ft)
beyond each fire damper; and
iv) The ducts are to be suitably supported and stiffened;
or
v) Constructed of steel in accordance with 5-1-1/5.29i) and 5-1-1/5.29iv) above; and
vi) Insulated to “A-60” standard throughout the accommodation spaces, service spaces or control stations.

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Chapter 1 Passive Fire Protection
Section 1 General 5-1-1

5.29.1
The galley ventilation system may also serve other spaces associated to the galley (pantry with no
cooking appliances, provisions store, dry goods store, scullery room) if all the following conditions
are satisfied:
i) The galley and the associated space have a common boundary,
ii) The associated space is surrounded by A-rated divisions,
iii) An automatic fire damper with manual closures from both sides and fitted with position
indicator is to be installed at the common boundary penetrated, regardless of the size of the
duct,
iv) The fire damper is to be connected to the Air-conditioning and Heating Unit (AHU) control
panel such that upon loss of power to the AHU fan, the fire damper closes,
v) Fire detection in accordance with the requirements of 5-2-5/1.1 is to be installed in the
associated space, such that upon detection of fire, the AHU shuts down and the fire damper
in the common bulkhead closes, and
vi) At least one means of egress for the associated space, independent from the galley egress, is
to be provided.

5.31
Ducts provided for ventilation of accommodation and service spaces or control stations are not to pass through
machinery spaces of Category A hazardous areas or galleys. However, a relaxation from this requirement,
except for the ducts passing through hazardous areas, will be considered, provided:
i) The ducts where they pass through a machinery space of category A or a galley are constructed of
steel in accordance with 5-1-1/5.29i) and 5-1-1/5.29iv).
ii) Automatic fire dampers are fitted close to the boundaries penetrated; and
iii) The integrity of the machinery space or galley boundaries is maintained at the penetrations;
or
iv) The ducts where they pass through a machinery space of category A or a galley are constructed of
steel in accordance with 5-1-1/5.29i) and 5-1-1/5.29iv); and
v) Are insulated to “A-60” standard within the machinery space or galley.

5.33 (2018)
Ventilation ducts having an internal cross-sectional area greater than 0.02 m2 (0.22 ft2) penetrating “B”
class bulkheads are to be steel or lined with steel sheet sleeves at least 1.8 mm (0.07 in.) thick and at least
900 mm (35.4 in.) long (preferably 450 mm (17.7 in.) on each side of the division). Ventilation ducts having
an internal cross-sectional area 0.02 m2 (0.22 ft2) or less are to be steel or lined with steel sheet sleeves at
least 1.8 mm (0.07 in.) thick and at least 200 mm (7.88 in.) long (preferably 100 mm (3.93 in.) on each side
of division). See 5-1-1/Figure 4.

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Chapter 1 Passive Fire Protection
Section 1 General 5-1-1

FIGURE 4
Ventilation Ducts Penetrating “B” Class Divisions (2018)
(1) Steel Duct (2) Non-steel (non-combustible) Duct

Division

Gap to be kept minimum

(max. 2.5 mm (0.10 in.)

L L
t ≥ 1.8 mm (0.07 in.) Steel sleeve
t ≥ 1.8 mm (0.07 in.)

L = 450 mm for sectional area greater than 200 cm2

= 100 mm for sectional area of 200 cm2 or less

5.35
Exhaust ducts from galley ranges are to be “A” class fire division integrity or equivalent where they pass
through accommodation spaces or spaces containing combustible materials.

5.37 (2012)
Each galley exhaust duct is to be fitted with:
i) A grease trap readily removable for cleaning;
ii) A fire damper located in the galley end of the duct which is automatically and remotely operated
and, in addition a remotely operated fire damper located in the exhaust end of the duct;
iii) Arrangements, operable from within the galley, for shutting off the exhaust fans; and
iv) Fixed means for extinguishing a fire within the duct.

5.39
All ventilation systems’ main inlets and outlets are to be capable of being closed from outside the space
being ventilated.

5.41
Power ventilation of accommodation spaces, service spaces, control stations, machinery spaces and hazardous
areas are to be capable of being stopped from an easily accessible position outside the space being served
and in the event of a fire in the space served. The means for stopping the power ventilation serving machinery
spaces or hazardous areas are to be entirely separate from the means provided for stopping ventilation of
other spaces.

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Section 1 General 5-1-1

5.43
Windows and sidescuttles in boundaries which are required to meet an “A-60” standard which face the
drill floor area are to be:
i) Constructed to an “A-60” standard; or
ii) (1999) Protected by a water curtain system on the exposed wall. The water curtain system should
be designed to provide a discharge rate of 6.0 liters per minute per square meter (0.15 gpm per
square foot); or
iii) Fitted with shutters of steel or equivalent material.

5.45
The ventilation of the accommodation spaces and control stations are to be arranged in such a way as to
prevent the ingress of flammable, toxic or noxious gases, or smoke from surrounding areas.

5.47 (2012)
In addition to the air balancing openings as permitted in 5-1-1/5.5, air balancing ducts (jumper ducts) may
be fitted only when all the following conditions are complied with:
i) The air balancing ducts are connecting two service spaces or a service space with a machinery
space other than a Category A machinery space or two machinery spaces other than Category A
machinery spaces.
ii) The spaces connected are located outside the accommodation deckhouse.
iii) The air balance duct is 3 mm (0.12 in.) thick, 900 mm (35.4 in.) long (preferably 450 mm (17.7 in.)
on each side) and fitted with a fire damper close to the boundary penetrated.
iv) The fire damper is to be automatically operated upon detection of smoke in any of the spaces
connected and remotely operated from a normally manned control station where the fire-detection
main indicator board for the spaces concerned is located. In addition, the fire damper is to be capable
of being closed locally.
Air balancing openings between hazardous areas, such as openings between mud tank room and mud
tanks, will be specially considered.

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PART Chapter 2: Active Fire Protection Systems and Equipment

5
CHAPTER 2 Active Fire Protection Systems and Equipment

CONTENTS
SECTION 1 General .................................................................................................. 17
1 Governmental Authority .................................................................... 17
3 Plans and Specifications ................................................................... 17
3.1 General.......................................................................................... 17
3.3 Fire Control Plans .......................................................................... 17

SECTION 2 Fixed Fire Fighting Systems ............................................................... 19

1 Fire Main Systems ............................................................................ 19
1.1 Fire Pumps .................................................................................... 19
1.3 Fire Main ....................................................................................... 21
1.5 Hydrants, Hoses and Nozzles ....................................................... 21

FIGURE 1 International Shore Connection .............................................. 22

SECTION 3 Additional Fixed Fire Fighting Systems ............................................. 23

1 Fixed Fire Fighting Systems ............................................................. 23
1.1 Spaces Containing Specific Equipment ......................................... 23
1.3 Drilling and Industrial Areas........................................................... 23
3 Gas Smothering ................................................................................ 24
3.1 General.......................................................................................... 24
3.3 Carbon Dioxide Systems ............................................................... 26
5 Foam ................................................................................................. 26
5.1 Fixed High Expansion Foam Systems ........................................... 26
5.3 Low Expansion Foam System ....................................................... 26
7 Fixed Pressure Water Spraying and Automatic Sprinkler
Systems ............................................................................................ 26
8 Clean Agent Fire Extinguishing Systems.......................................... 26
8.1 Fire Suppression Agent ................................................................. 27
8.3 Fire Tests ...................................................................................... 27
8.5 System Components ..................................................................... 27
8.7 System Installation ........................................................................ 27
9 Protection of Helicopter Decks and Refueling Facilities ................... 28
9.1 General.......................................................................................... 28
9.3 Firefighting Systems ...................................................................... 29
11 Paint and Flammable Liquid Lockers................................................ 30
11.1 Lockers of 4 m2 (43 ft2) or More Floor Area and Lockers with
Access to Accommodation Spaces ................................................ 30
11.3 Lockers of Less Than 4 m2 (43 ft2) Floor Area Having no Access
to Accommodation Spaces ............................................................ 30

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 13 Spaces Containing Equipment with Oil Filled Capacitors .................31

TABLE 1 Minimum Steel Pipe Wall Thickness for CO2 Medium

Distribution Piping ...................................................................25

SECTION 4 Portable Fire Fighting Systems ........................................................... 32

1 Portable Fire Extinguishers and Sand ..............................................32
1.1 Extinguishers ................................................................................. 32
1.3 Sand .............................................................................................. 32
3 Fire-Fighters’ Outfit ...........................................................................32
3.1 Number .......................................................................................... 32
3.3 Breathing Apparatus ...................................................................... 32
3.5 Recharging of Air Cylinders ........................................................... 32
3.7 Lifeline ........................................................................................... 33
3.9 Safety Lamp and Axe .................................................................... 33
3.11 Boots and Gloves .......................................................................... 33
3.13 Helmet ........................................................................................... 33
3.15 Protective Clothing......................................................................... 33
3.17 Two-way Portable Radiotelephone ................................................ 33

TABLE 1 Classification of Portable and Semi-portable Extinguishers ...33

TABLE 2 Hand Portable Fire Extinguishers and Semi-portable Fire-
Extinguishing Systems ...........................................................34

SECTION 5 Fire and Gas Detection ........................................................................ 36

1 Other Fire Protection Requirements .................................................36
1.1 Fire Detection and Alarm Systems ................................................ 36
1.3 General Alarm ............................................................................... 37
1.5 Public Address ............................................................................... 37
1.7 Mud Tank Level Alarm ................................................................... 37
1.9 Ventilation System Alarms ............................................................. 37
3 Gas Detection and Alarm Systems ...................................................37
5 Hydrogen Sulfide Detection and Alarm.............................................38
5.1 Areas for Protection ....................................................................... 38
5.3 Alarms ........................................................................................... 38
5.5 Portable Hydrogen Sulfide Gas Detectors ..................................... 38
7 Respiratory Protection Equipment for Hydrogen Sulfide ..................38
7.1 Self-contained Breathing Apparatus (SCBA) ................................. 38
7.3 Air Line Breathing Equipment ........................................................ 38

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PART Section 1: General

5
CHAPTER 2 Active Fire Protection Systems and Equipment

SECTION 1 General

1 Governmental Authority (1999)

Attention is drawn to the appropriate governmental authority in each case, as there may be additional
requirements, depending on the size, type and intended service of the unit, as well as other particulars and
details. Consideration will be given to fire extinguishing systems which comply with the published
requirements of the governmental authority in which the unit is to be registered, as an equivalent alternative
or addition to the requirements of this section.

3 Plans and Specifications

3.1 General
The following plans together with supporting data and particulars are to be submitted.
• Arrangement and details of fire main systems
• Foam smothering systems
• Other fire extinguishing arrangements.
• Fire control plans
• Fire detection systems
• Fixed fire extinguishing systems
• Fire extinguishing appliances
• Control station for emergency closing of openings and stopping machinery
• Gas detection systems
• Fireman’s outfits
• (2010) The most severe service condition for the operation of the emergency fire pump (e.g., lightest
draft as shown in Trim and Stability Booklet, etc.)
• (2010) Calculations and pump data demonstrating that the emergency fire pump system can meet the
operational requirements specified in 5-2-2/1.1 with the proposed pump location and piping arrangements
(e.g., adequate suction lift, discharge pressure, capacity, etc.) at the most severe service condition

3.3 Fire Control Plans (2013)

Fire control plans are to be permanently exhibited for the guidance of operating personnel, showing clearly
for each deck provision, location, controls and particulars, as applicable, of the following:
i) Locations of fire control stations
ii) Various fire sections enclosed by various classes of fire divisions
iii) Arrangement of fire detectors and manual fire alarm stations
iv) Arrangement of combustible gas detectors

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Section 1 General 5-2-1

v) Arrangement of hydrogen sulfide gas detectors

vi) Locations of respiratory protection equipment for hydrogen sulfide
vii) General alarm actuating positions
viii) Arrangement of various fire-extinguishing appliances
ix) Locations of firefighter’s outfits
x) Location of helicopter crash kit
xi) Arrangement of water spray nozzles and sprinklers (if fitted)
xii) Locations of emergency shutdown (such as oil fuel source shutdown, engine shutdown, etc.) stations
xiii) The Ventilating system including fire dampers positions, ventilating fans control positions with
indication of identification numbers of ventilating fans serving each section
xiv) Arrangement of fire/watertight doors and their remote control positions
xv) Blowout preventer control positions
xvi) Escape route and means of access to different compartments, decks, etc.
xvii) Locations of Emergency Escape Breathing Devices (EEBD); and
xviii) Arrangement of emergency muster stations and life-saving appliances.

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PART Section 2: Fixed Fire Fighting Systems

5
CHAPTER 2 Active Fire Protection Systems and Equipment

SECTION 2 Fixed Fire Fighting Systems

1 Fire Main Systems

1.1 Fire Pumps

1.1.1 Number of Pumps (2012)
There are to be at least two independently-driven fire pumps. The pumps, their source of power,
and piping and valves are to be arranged so that a fire in any one compartment will not put all fire
pumps out of action. See 4-2-6/25 for raw water systems in self-elevating units.
1.1.2 Location of Pumps
1.1.2(a) Location. The two main fire pumps are to be in separate compartments having no direct
access between them. Where this is impracticable, special consideration will be given to accesses
as follows,
i) A watertight door capable of being operated locally from both sides of the bulkhead, and
from a safe and accessible location outside of these spaces. For unattended propulsion
machinery space operation, this door is to be operable from the fire fighting station; or
ii) An air lock consisting of two gastight steel doors. The doors are to be self-closing without
any hold back arrangements.
iii) In addition to the arrangements specified in i) or ii) above, a second protected means of
access is to be provided to the space containing the fire pumps.
Common boundaries are to be at least A-0 construction, except if more than one bulkhead or deck
is common, the boundaries are to be at least A-60 construction.
1.1.2(b) Remote Operation. Valves and pumps in the fire-fighting system which are not readily
accessible are to be provided with means for remote operation.
1.1.3 Type of Pumps
Sanitary, ballast, bilge or general-service pumps may be accepted as one of the fire pumps, provided
that they are not normally used for pumping oil and that if they are subject to occasional duty for
the transfer or pumping of fuel oil, suitable changeover arrangements are fitted.
1.1.4 Pressure (1996)
The pressure for the purpose of determining fire pump capacity in accordance with 5-2-2/1.1.5(a)
is to be at least 3.5 bar (3.5 kgf/cm2, 50 psi) at the hydrant.
The maximum pressure at any hydrant shall be such that the effective control of a fire hose can be
demonstrated.

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1.1.5 Pump Capacity

1.1.5(a) General (2017). Each of the fire pumps required by 5-2-2/1.1.1 is to have a capacity
sufficient to deliver, while maintaining the pressure specified in 5-2-2/1.1.4, two jets of water
from nozzles that are connected to the two hydrants at which the pressure drop from the fire pump
discharge pressure will be the greatest.
Where a fire pump is utilized for the foam system provided for helicopter deck protection, the
pump is also to be capable of maintaining a pressure at the foam station as specified in 5-2-3/9.3.4.
If the water consumption for any other fire protection or fire-fighting purposes exceed the rate of
the helicopter deck foam installation, this consumption is to be the determining factor in calculating
the required capacity of each of the fire pumps.
In no case is the single pump capacity to be less than 25 m3/hr (110 gal/min.).
1.1.5(b) Ship-Type Drilling Units.
i) Total Pump Capacity. For ship-type units, the fire pumps required by 5-2-2/1.1.1 are to
be capable of delivering for fire-fighting purposes a quantity of water, at the appropriate
pressure prescribed, not less than four-thirds of the quantity required under 4-2-4/7.3 to
be dealt with by each of the independent bilge pumps when employed on bilge pumping,
using in all cases L = length of the unit as defined in 3-1-1/3 of the ABS Rules for
Building and Classing Steel Vessels (Steel Vessel Rules), except that the total required
capacity of the fire pumps need not exceed 180 m3/hr (792 gal/min.).
ii) Individual Pump Capacity. Each of the fire pumps required by 5-2-2/1.1.1 is to have a
capacity not less than 80% of the total required capacity divided by the number of required
pumps but not less than that required by 5-2-2/1.1.5(a) above. Where more pumps than
required are installed, their capacity will be subject to special consideration.
1.1.6 Relief Valves
In conjunction with all fire pumps, relief valves are to be provided if the pumps are capable of
developing a pressure exceeding the design pressure of the water-service pipes, hydrants and
hoses. These valves are to be so placed and adjusted as to prevent excessive pressure in any part
of the fire main system. In general, the relief valve is to be set to relieve at no greater than 1.7 bar
(1.75 kgf/cm2, 25 psi) in excess of the pump pressure necessary to maintain the requirements of
5-2-2/1.1.4.
1.1.7 Water Supply (2013)
1.1.7(a) Water Supply Sources. At least two water supply sources (sea chests, valves, strainers
and pipes) are to be provided and so arranged that one supply source failure will not put all supply
sources out of action.
1.1.7(b) Additional Measures. For self-elevating units, the following additional fire water supply
measures are to be provided:
i) Water is to be supplied from sea water main filled by at least two submersible pumping
systems. One system failure will not put the other system(s) out of function, and
ii) Water is to be supplied from drill water system while unit is lifting or lowering. Water
stored in the drill water tank(s) is to be not less than 40 m3 (10567 gallons) plus engine
cooling water consumption before unit lifting or lowering. Alternatively, water may be
supplied from buffer tank(s) in which sea water stored is not less than the quantity as the
above mentioned.
1.1.8 Pressurized Main Water Supply
Where fire pumps take suction from a pressurized water main system (i.e., a system not utilizing
an intermediate tank supply as on self-elevating units), precautions are to be taken to ensure that
an adequate supply of water is maintained. The arrangement of water supply, their source of power,
valves, their control means and piping are to be arranged so that a fire in one compartment will
not jeopardize the essential supply of water.

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Chapter 2 Active Fire Protection Systems and Equipment
Section 2 Fixed Fire Fighting Systems 5-2-2

1.3 Fire Main

1.3.1 Size
The diameter of the fire main and water-service pipes is to be sufficient for the effective distribution
of the maximum required discharge from two fire pumps operating simultaneously, except that the
diameter need only be sufficient for the discharge of 140 m3/hr (616 gal/min.).
1.3.2 Cocks or Valves
A valve is to be fitted to serve each fire hose so that any fire hose may be removed while the fire
pumps are at work.
1.3.3 Isolation (2013)
Isolating valves and other arrangements, as necessary, are to be provided so that if a fire pump and
its associated piping within its compartment are rendered inoperable, the fire main can be pressurized
with a fire pump located in another compartment.
In addition, the fire main is to be provided with isolation valves located such that damage to any part
of the system (e.g., by fire or explosion) would result in the loss of a minimum number of hydrants,
water spray branches or foam water supplies, as practicable, and permit the optimum utilization of
the remaining fire main.
1.3.4 Cold Weather Protection
Fire main systems are to be provided with drains, circulation loops or other means for cold weather
protection.
1.3.5 Materials (1997)
Materials readily rendered ineffective by heat are not to be used for fire mains unless adequately
protected. In order to be considered not “readily rendered ineffective by heat”, a component is to
be certified as having passed an applicable recognized fire test, or the material is to have a melting
temperature higher than the test temperature specified in an applicable fire test.
1.3.6 Connections (2009)
In general, the fire main should not have connections other than those necessary for fire fighting
purposes. Connections to non-continuous services will be specially considered on the basis of the
fire main system being able to supply the required fire fighting services in conjunction with
simultaneous operations of the other connected services. Isolation valves are to be installed for all
open deck fire main branches used for purposes other than fire fighting.

1.5 Hydrants, Hoses and Nozzles

1.5.1 Hydrants (1997)
The number and position of the hydrants are to be such that at least two jets of water not emanating
from the same hydrant, one of which is to be from a single length of hose, may reach any part of
the unit normally accessible to the passengers or crew while the unit is being navigated.
The pipes and hydrants are to be so placed that the fire hoses may be easily coupled to them. In
units where equipment or stores may be carried on deck, the positions of the hydrants are to be
such that they are always readily accessible and the pipes are to be arranged, as far as practicable,
to avoid risk of damage by such equipment or stores.
Materials readily rendered ineffective by heat are not to be used for hydrants. See 5-2-2/1.3.5.
1.5.2 Hoses (2012)
Each of the hydrants required by 5-2-2/1.5.1 is to be provided with a fire hose complete with couplings
and nozzles. Additionally, at least one complete fire hose assembly is to be carried as a spare.
Fire hoses are to be certified by a competent independent testing laboratory as being constructed
of nonperishable material to recognized standards. Fire hoses are to have a length of at least 10 m
(33 ft), but not more than:

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i) 15 m (50 ft) in machinery spaces;

ii) 20 m (66 ft) in other spaces and open decks; and
iii) 25 m (82 ft) for open decks with a maximum width in excess of 30 m (98 ft).
Each hose is to be provided with a dual purpose nozzle in accordance with 5-2-2/1.5.3 and necessary
couplings. Fire hoses together with any necessary fittings and tools are to be kept ready for use in
conspicuous positions near the water-service hydrants of connections.
1.5.3 Nozzles (2013)
Dual purpose combined jet spray nozzles are to be fitted throughout the unit with a minimum nozzle
diameter of 12 mm (1/2 in.) for accommodation and service spaces and with a maximum diameter
of 19 mm (3/4 in.) for machinery spaces and exterior locations. Fire hose nozzles of plastic type
material such as polycarbonate may be accepted, subject to review of their capacity and serviceability
as marine use fire hose nozzles.
1.5.4 International Shore Connection
For surface type units, at least one international shore connection, as shown in 5-2-2/Figure 1, is
to be provided and kept aboard the unit together with gasket, bolts and eight washers. Facilities
are to be available enabling such a connection to be used on either side of the unit.

FIGURE 1
International Shore Connection
Coupling permanently attached that will
fit the vessel's hydrants and hose.
14.5 mm (9/16 in.)min.

Flat Face

64 mm
(21/2 in.)
132 mm
(51/4 in.)

178 mm
(7 in.)

19 mm
(3/4 in.)

Bolts: 4, each of 16 mm ( 5/8 in.) diameter, 50 mm (2 in.) in length

Flange Surface: Flat face
Material: Any suited for 10 bar (10.5 kgf/cm 2, 150 psi)
Gasket: Any suited for 10 bar (10.5 kgf/cm 2, 150 psi) service

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PART Section 3: Additional Fixed Fire Fighting Systems

5
CHAPTER 2 Active Fire Protection Systems and Equipment

SECTION 3 Additional Fixed Fire Fighting Systems

1 Fixed Fire Fighting Systems (2013)

1.1 Spaces Containing Specific Equipment (2014)

A fixed firefighting system complying with 5-2-3/3, 5-2-3/5 or 5-2-3/7 is to be provided in each space
containing the following equipment:
i) Main or auxiliary oil-fired boilers and other processes of equivalent thermal rating.
ii) Oil fuel units (as defined by 5-3-1/9.7)
iii) Internal combustion machinery used for main propulsion
iv) Internal combustion machinery used for purposes other than main propulsion having a total power
output of not less than 750 kW (1000 hp).
v) Settling tanks for boilers
vi) Equipment with oil filled capacitors.
Where a fixed fire extinguishing system not required by i) through v) is installed, such system is to meet
the applicable requirements of 5-2-3/3, 5-2-3/5, or 5-2-3/7 and is to be submitted for approval.

1.3 Drilling and Industrial Areas (2015)

1.3.1 Fixed Fire Extinguishing Systems on Drilling Area and Temporary Well Test Area, and
Moonpool Area (2018)
The Drilling Area is the drill floor area extending to each corner of the derrick including choke &
kill manifold. The following firefighting arrangement is to be provided for the area:
i) A fixed water spray system is to be provided to protect drilling area and temporary well test
area. The minimum water application rate is not less than 20.4 l/min/m2 (0.5 gpm/ft2), or
ii) At least two dual-purpose (jet/spray) fire monitors are to be installed to cover drilling area,
well test area, and temporary well test area. The minimum capacity of each monitor is not
less than 100 m3/h (440 gpm). The monitors may be operated either remotely or locally.
Monitor arranged for local operation should be sited on an accessible protected position.
The above firefighting arrangement is also to be provided for both inside of moonpool and the bunded
area (coaming) surrounding to the moonpool when the bottom of the moonpool is submerged
below waterline.
1.3.2 Fixed Fire Extinguishing Systems on Mud Processing Area
The Mud Processing Area includes:
i) Spaces occupied by the open mud circulating system which contain hazardous areas, such
as spaces containing gumbo box, shale shaker, degasser, desander, desilter, centrifuge, mud
cleaner, etc.
ii) Spaces with open-top mud pits which will be used for oil-based mud.

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The following firefighting arrangement is to be provided for the area:

A suitable fixed foam system is to be provided. The system is to be capable of delivering foam
solution at a rate of not less than 6.5 l/min/m2 (0.16 gpm/ft2) [(4.1 l/min/m2 (0.10 gpm/ft2) for
Aqueous Film Forming Foam or Film-Forming Fluoroprotein Foam)] for 15 minutes. Alternatively,
a gas fixed fire extinguishing system may be used for enclosed mud processing areas.

3 Gas Smothering

3.1 General
3.1.1 Storage (2013)
Where the gas smothering medium is stored outside of the protected space, the storeroom is to be
situated in a safe and readily accessible position and is to be effectively ventilated by a ventilation
system independent of all other spaces.
Spaces for storage of cylinders or tanks for extinguishing gas are not to be used for other purposes.
These spaces are not to be located forward of the forward collision bulkhead, when fitted. Access
to these spaces is to be possible from the open deck. Spaces situated below the deck are to be
located no more than one deck below the open deck.
Spaces where entrance from the open deck is not provided or which are located below deck are to
be fitted with mechanical ventilation. The exhaust duct (suction) is to be lead to the bottom of the
space. Such spaces are to be ventilated with at least six air changes per hour.
3.1.2 Design (2018)
Containers and associated pressure components are to be designed based upon an ambient temperature
of 55°C (131°F).
For CO2 fire extinguishing systems, the wall thickness of steel piping is to be suitable for the
pressure and not less than the thickness identified in 5-2-3/Table 1. Column A is for piping from
storage containers to distribution station, and column B is for piping from distribution station to
nozzles. For other fixed gas fire extinguishing systems, calculations showing compliance with
4-2-2/5.7 are to be submitted for approval.
Where the fire-extinguishing medium is used as the power source for the pre-discharge alarm, the
piping to the alarm is to comply with Column B of 5-2-3/Table 1.
The pressure rating of pipe connections such as flanges from the distribution aftermost valve to
discharge nozzles is to be not less than the maximum pressure developed during the discharge of
CO2 into protected spaces.
The relief valve of a CO2 fire extinguishing system is to discharge outside of the CO2 container
storage compartment, in a safe area. In addition, in piping sections where valve arrangements introduce
sections of closed piping, such sections are to be fitted with a pressure relief valve and the outlet
of the valve is to be led to open deck.
Gray cast iron piping components are not to be used for fixed gas fire extinguishing systems. All
discharge piping, fittings and nozzles in the protected spaces are to be constructed of materials
having a melting temperature which exceeds 925°C (1697°F). The piping and associated equipment
are to be adequately supported.
Threaded joints in CO2 systems are to be allowed only inside protected spaces and in CO2 cylinder
rooms.

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Chapter 2 Active Fire Protection Systems and Equipment
Section 3 Additional Fixed Fire Fighting Systems 5-2-3

TABLE 1
Minimum Steel Pipe Wall Thickness for CO2
Medium Distribution Piping (2013)
Nominal OD A B Nominal OD A B
size, mm mm mm mm size, in. in. in. in.
15 21.3 2.8 2.6 1/2 0.840 0.110 0.102
20 26.9 2.8 2.6 3/4 1.050 0.110 0.102
25 33.7 4.0 3.2 1 1.315 0.157 0.126
32 42.4 4.0 3.2 11/4 1.660 0.157 0.126
40 48.3 4.0 3.2 11/2 1.9 0.157 0.126
50 60.3 4.5 3.6 2 2.375 0.177 0.142
65 76.1 5.0 3.6 21/2 2.875 0.197 0.142
80 88.9 5.5 4.0 3 3.5 0.220 0.157
90 101.6 6.3 4.0 31/2 4.0 0.248 0.157
100 114.3 7.1 4.5 4 4.5 0.28 0.177
125 139.7 8.0 5.0 5 5.563 0.315 0.197
150 168.3 8.8 5.6 6 6.625 0.346 0.22
Notes:
1 The above minimum thicknesses are derived from those thicknesses available in ISO
4200 Series 1 (OD), JIS (N.P.S.), or ASTM (N.P.S.). Diameter and thickness according
to other recognized standards will be accepted.
2 For threaded pipes, where approved, the thickness is to be measured to the bottom of
the thread.
3 The internal surface of pipes outside of the engine room is to be galvanized.
4 For larger diameters the minimum wall thickness will be subject to special consideration
by ABS.
5 In general, the minimum thickness is the nominal wall thickness and no allowance need be
made for negative tolerance or reduction in thickness due to bending.

3.1.3 Alarm (1995)

(2017) Means are to be provided for automatically giving audible and visual warning of the release of
fire extinguishing gas into any space to which personnel normally have access. The audible alarms
are to be located so as to be audible throughout the protected space with all machinery operating,
and the alarms are to be distinguished from other audible alarms by adjustment of sound pressure
or sound patterns. The alarm is to operate for at least a 20 second period before the gas is released.
Alarms may be pneumatically (by the extinguishing medium or by air) or electrically operated.
3.1.3(a) Electric. If electrically operated, the alarms are to be supplied with power from the main
and an emergency source of electrical power.
3.1.3(b) Pneumatic. If pneumatically operated by air, the air supply is to be dry and clean, and the
supply reservoir is to be automatically kept charged at all times and is to be fitted with a low pressure
alarm. The air supply may be taken from the starting air receivers. Any stop valve fitted in the air
supply line is to be locked or sealed in the open position. Any electrical components associated with
the pneumatic system are to be powered from the main and an emergency source of electrical power.
3.1.3(c) Uninterruptible Power Supply (2013). For fire extinguishing systems that protect the
machinery space containing the main source of power, instead of the power supply arrangements
required above for electrically operated alarms and electrical components associated with pneumatic
alarms, an uninterruptible power supply which is supplied with power from the emergency
switchboard is to be provided.

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3.1.4 Controls
Except as otherwise permitted herein two independent manual control arrangements are to be
provided, one of them being positioned at the storage location and the other in a readily accessible
position outside of the protected space.

3.3 Carbon Dioxide Systems (2013)

In addition to the applicable requirements of 4-7-3/3.3 of the Steel Vessel Rules, fixed carbon dioxide fire
extinguishing systems are to be in accordance with Chapter II-2, Regulations 10.4.2 and 10.4.3 of the
International Convention for the Safety of Life at Sea (SOLAS) 1974 and Amendments in force, and with
Chapter 1.4 and Chapter 5 of the International Code for Fire Safety Systems. Fixed low pressure carbon
dioxide systems are to be in accordance with 4-7-3/3.5 of the Steel Vessel Rules.

5 Foam

5.1 Fixed High Expansion Foam Systems (1 July 2009)

In addition to the applicable requirements of the Rules, fixed high expansion foam systems are to be in
accordance with Chapter 6.2.1 and 6.2.2 of the International Code for Fire Safety Systems.
Fixed foam fire-extinguishing systems using inside air are to be designed, constructed and tested in
accordance with the requirements identified in MSC.1/Circ. 1271 Guidelines for the Approval of High-
Expansion Foam Systems Using Inside Air for the Protection of Machinery Spaces and Cargo Pump-Rooms.
Foam concentrates are to be of an approved type.*
* Note: Reference is made to the International Maritime Organization MSC/Circular 670 “Guidelines for the Performance
and Testing Criteria, and Surveys of High-Expansion Foam Concentrates for Fixed Fire-Extinguishing Systems.”

5.3 Low Expansion Foam System

5.3.1 Application
Low expansion foam systems may be fitted in machinery spaces in addition to the required fixed
fire extinguishing system.
5.3.2 Design (1998)
In addition to the applicable requirements of the Rules, fixed low expansion foam systems are to
be in accordance with Chapter 6.2.1, 6.2.2, and 6.2.3 of the International Code for Fire Safety
Systems. Foam concentrates are to be of an approved type.**
** Note: Reference is made to the International Maritime Organization MSC/Circular 582 “Guidelines for the
Performance and Testing Criteria, and Surveys of Low-Expansion Foam Concentrates for Fixed Fire-
Extinguishing Systems.”

7 Fixed Pressure Water Spraying and Automatic Sprinkler Systems

(2017)
In addition to the applicable requirements of the Rules, fixed water spraying systems and automatic sprinkler
systems are to be in accordance with Chapters 7 and 8 of the International Code for Fire Safety Systems.

8 Clean Agent Fire Extinguishing Systems (2013)

Fixed gas fire-extinguishing systems equivalent to those specified in 5-2-3/3 through 5-2-3/7 are to be
submitted for approval, based on the guidelines specified in the IMO MSC/Circ. 848 as amended by
MSC/Circ. 1267 and this subsection.
Fire extinguishing systems using Halon 1211, 1301, and 2402 and perfluorocarbons are prohibited. The
use of a fire-extinguishing medium, which either by itself or under expected conditions of use gives off
toxic gases, liquids and other substances in such quantities as to endanger persons, is not permitted.

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Section 3 Additional Fixed Fire Fighting Systems 5-2-3

8.1 Fire Suppression Agent

The agent is to be recognized as a fire extinguishing medium by NFPA Standard 2001 or other recognized
standard. The minimum extinguishing concentration for net volume total flooding of the protected space at
the lowest expected operating temperature, but not greater than 0°C (32°F), is to be determined by an
acceptable cup burner test. The minimum design concentration is to be at least 30% above the minimum
extinguishing concentration and is to be verified by full-scale test (see 5-2-3/8.3).
The fire extinguishing agent is to be acceptable for use in occupied spaces by U.S. EPA or other recognized
organization. The concentrations for cardiac sensitization NOAEL (No Observed Adverse Effect Level),
LOAEL (Lowest Observed Adverse Effect Level) and ALC (Approximate Lethal Concentration) are to be
submitted.

8.3 Fire Tests

The system is to pass the fire tests in the Appendix of the IMO MSC/Circ. 848 as amended by MSC/Circ.
1267. The testing is to include the system components.
The system is to pass an additional fire test (number 1 in the Appendix of MSC/Circ. 848) with the agent
storage cylinder at the lowest expected operating temperature, but not greater than 0°C (32°F).

8.5 System Components

The system is to be suitable for use in a marine environment. Major components (valves, nozzles, etc.) are
to be made of brass or stainless steel, piping is to be corrosion resistant (stainless steel or galvanized) and
the material is to have a melting point of not less than 927°C (1700°F).
The system and its components are to be designed, manufactured and installed in accordance with recognized
standards.
Containers and associated pressure components are to be designed based upon an ambient temperature of
55°C (131°F).
Minimum wall thickness for distribution piping is to be in accordance with 5-2-3/Table 1 (Columns A or B,
as applicable).

8.7 System Installation

8.7.1 Storage
As far as practicable, the fire suppression agent is to be stored outside the protected space in a
dedicated storeroom. The storeroom is to be in accordance with 5-2-3/3.1.1, except that when
mechanical ventilation is provided, the location of the exhaust duct (suction) is dependent on the
density of the agent relative to air.
When allowed by the flag Administration, the fire suppression agent may be stored inside the
protected space. In addition to the related instructions from the flag Administration, the installation
is to be in accordance with paragraph 11 of IMO MSC/Circ. 848 as amended by MSC.1/Circ. 1267.
In the case of new installation in existing units, the storage of the fire suppression agent within a
low fire risk space with a net volume at least two (2) times greater than the net volume of the
protected space may be specially considered, based on the type of agent and the possible hazards
for the personnel within the space.
8.7.2 Alarm
An audible and visual predischarge alarm in accordance with 5-2-3/3.1.3 and paragraph 6 of IMO
MSC/Circ. 848 as amended by MSC.1/Circ. 1267 is to be provided.
8.7.3 Controls (2017)
Except as otherwise permitted herein two independent manual control arrangements are to be
provided, one of them being positioned at the storage location and the other in a readily accessible
position outside of the protected space.

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Automatic actuation is not permitted when the protected space is normally manned or interferes
with the safety navigation of the vessel. If the protected space is normally unmanned and may be
entered occasionally for brief periods such as for repairs, maintenance or other purpose, automatic
actuation may be allowed in addition to manual actuation, provided that the following conditions
are met
i) The egress from the protected space is horizontal. Exit doors from the spaces are to be
outward-swinging self-closing doors (i.e., opening in the direction of escape routes) which
can be opened from the inside, including when the doors are locked from the outside.
ii) Notices that the space is protected by an automatic activation system are prominently
posted at the entrance to the space.
iii) A switch is provided near the entrance to disable the automatic release feature of the system.
The switch is to have an indicator of its status such as red pilot light to indicate when the
switch is activated (automatic release feature disabled). A sign is to be posted near the switch
indicating that the automatic release feature is to be disabled when the space is occupied
and that the automatic actuation is to be enabled when leaving the space. The sign is to
also indicate that the manual release of the system remains enabled and the space is to be
vacated immediately when the release alarm sounds.
iv) When the automatic release feature is disabled, all other controls, alarms, etc., are to remain
activated.
v) An indicator at the control console is provided to indicate when the automatic release
feature has been disabled.
vi) The medium release warning alarm is to operate for the length of time needed to evacuate
the space, but in no case less than 30 seconds for space exceeding 6000 ft3 (170 m3) and
20 seconds for spaces 6000 ft3 (170 m3) or less before the medium is released.
vii) The automatic release of a clean agent fire extinguishing system is to be approved by the
vessel’s flag Administration.
8.7.4 Nozzles
The nozzle type, maximum nozzle spacing, maximum height and minimum nozzle pressure are to
be within the limits to provide fire extinction as tested and verified in the appropriate fire test (see
5-2-3/8.3).

9 Protection of Helicopter Decks and Refueling Facilities (2011)

9.1 General (2018)

Where areas of a unit are designated for helicopter operations, details of the facilities are to be submitted
and the firefighting systems of 5-2-3/9.3 are to be provided and stored near the access to those areas.
Deckhouse tops directly below helicopter decks are to have no openings. See 4-2-6/17 for helicopter deck
drainage.
Helidecks which form the deckhead (roof) of the accommodations are to be insulated to an “A-60” class
standard.
All helidecks are to be constructed of steel or other material which provides equivalent structural and fire
integrity properties to that of steel.
If the Administration permits aluminum or other low melting point metal construction that is not made
equivalent to steel, the following provisions are to be satisfied:
i) If the helideck is cantilevered over the side of the unit, after each fire that may have an effect on
the structural integrity of the helideck or its supporting structures, the helideck is to undergo a
structural analysis to determine its suitability for further use; and
ii) If the helideck is located above the unit’s deckhouse or similar structure, the following conditions
are to be satisfied:

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a) The deckhouse top or other similar structures and bulkheads under the helideck are to
have no openings,
b) Windows under the helideck are to be provided with steel shutters. Alternatively, windows
are to be certified for A-60 applications in accordance with applicable requirements of
IMO FTP Code, and the arrangement is to be flag Administration approved.
c) After each fire on the helideck or supporting structure, the helideck is to undergo a
structural analysis to determine its suitability for further use.
A firefighting system as required by 5-2-3/9.3 is to be provided and arranged so as to adequately protect
both the helicopter deck and helicopter fuel storage areas where provided, see 4-2-6/7 for the fuel storage
requirements.

9.3 Firefighting Systems

9.3.1 Hoses and Nozzles
At least two approved combination solid stream and water spray nozzles and detachable applicators
and hoses sufficient in length to reach any part of the helicopter deck are to be provided.
9.3.2 Portable Extinguishers (2017)
The helicopter deck area is to be protected by at least two approved dry powder extinguishers of a
total capacity of not less than 45 kg (100 lb) , but not less than 9 kg each (see 5-2-4/Table 1 for
semi-portable extinguishers). At least one portable extinguisher is to be located at each helicopter
deck access point.
9.3.3 Back-up System
A back-up firefighting system is to be provided, consisting of CO2 extinguishers of a total capacity
of not less than 18 kg (40 lb) or equivalent, one of these extinguishers being equipped so as to
enable it to reach the engine area of any helicopter using the deck. The back-up system is to be located
so that the equipment would not be vulnerable to the same damage as the dry powder extinguishers
required by 5-2-3/9.3.2.
9.3.4 Fixed-Foam System (2013)
A fixed-foam fire-extinguishing system consisting of monitors or hose streams or both is to be
installed to protect the helicopter landing area in all weather conditions in which helicopters can
operate and fuel storage areas, when provided onboard. The helicopter landing area is the area
contained within a circle of diameter “D” where “D” is the distance across the main rotor and tail
rotor in the fore and aft line of a helicopter with a single main rotor and across both rotors for a
tandem rotor helicopter or the full area of the deck, whichever is less. The system is to be capable
of delivering foam solution at a rate of 6.0 liters per square meter per minute (0.15 gpm per square
foot) of the areas protected for at least five minutes. The pump is to be capable of maintaining a
pressure of 7 bar (7 kgf/cm2, 100 psi) at the foam installation. The foam agent is to meet the
performance standards for Level B foam in the International Civil Aviation Organization’s Airport
Services Manual (Part 1 Chapter 8, Paragraph 8.1.5, Table 8-1) and be suitable for use with sea water.
Foam delivery at the minimum application rate is to start within 30 seconds of system activation.
The operation of the foam system is not to interfere with the simultaneous operation of the fire
main.
9.3.5 Deck Integrated Fire Fighting System (DIFFS) (2015)
When permitted by the flag Administration, a deck integrated fire fighting system (DIFFS) may
be provided as an alternative to the fixed-foam fire-extinguishing system protecting the helicopter
landing area. DIFFS typically consist of a series of 'pop-up' nozzles, with both a horizontal and
vertical component, designed to provide an effective spray distribution of foam to the whole of the
landing area. DIFFS is to be capable of supplying performance level B foam solution at an application
rate and for a duration which at least meets the minimum requirements stated in 5-2-3/9.3.4 above.

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DIFFS performance criteria need to consider several pop-up nozzles rendered ineffective by the
impact of a helicopter on the landing area. The number of pop-up nozzles rendered ineffective by
a crash situation will depend on the pattern (spacing) of the nozzle arrangement and the type(s) of
helicopters operating to the helicopter deck, but not less than 15% of the nozzles installed. The
remaining pop-up nozzles are to be capable of delivering finished foam to the landing area at or
above the minimum application rate, considering the individual supply pipes to the damaged pop-
up nozzles ruptured.
DIFFS activation is to be initiated manually. Activation controls are to be located in at least two
positions having immediate access to the helicopter landing area and separated as far as practicable.
Foam delivery at the minimum application rate is to start within 30 seconds of system activation.
The operation of DIFFS is not to interfere with the simultaneous operation of the fire main.
Where a DIFFS is used in tandem with a passive fire-retarding system demonstrated to be capable
of removing significant quantities of unburned fuel from the surface of the helideck in the event of
a fuel spill from a ruptured aircraft tank, it is permitted to select a seawater-only DIFFS to deal
with any residual fuel burn. A seawater-only DIFFS, when permitted by the Flag Administration,
is to meet the same application rate and duration as specified for a performance level B foam
DIFFS in paragraphs 2.10 and 2.11 of CAP 437, as stated in this paragraph and 5-2-3/9.3.4 above.

11 Paint and Flammable Liquid Lockers (2001)

Paint and flammable liquid lockers or any similar service spaces used for the storage of flammable liquids
(such as solvents, adhesives, lubricants etc.) are to be protected by a fire-extinguishing arrangement enabling
the crew to extinguish a fire without entering the space. Unless required or permitted otherwise by the flag
Administration, one of the following systems is to be provided:

11.1 Lockers of 4 m2 (43 ft2) or More Floor Area and Lockers with Access to Accommodation
Spaces
Paint lockers and flammable liquid lockers of floor area 4 m2 (43 ft2) or more and also such lockers of any
floor area with access to accommodation spaces are to be provided with one of the fixed fire-extinguishing
systems specified below:
i) CO2 system, designed for 40 % of the gross volume of the space
ii) Dry powder system, designed for at least 0.5 kg/m3 (0.03 lb/ft3)
iii) Water spraying system, designed for 5 liters/m2/minute (0.12 gpm/ft2). The water spraying system
may be connected to the unit’s fire main system, in which case the fire pump capacity is to be
sufficient for simultaneous operation of the fire main system as required in 5-2-2/1.1.5 and the water
spray system. Precautions are to be taken to prevent the nozzles from being clogged by impurities
in the water or corrosion of piping, nozzles, valves and pump.
iv) Systems or arrangements other than those referenced above may be also considered, provided they
are not less effective.

11.3 Lockers of Less Than 4 m2 (43 ft2) Floor Area Having no Access to Accommodation
Spaces
For paint lockers and flammable liquid lockers of floor area less than 4 m2 (43 ft2) having no access to
accommodation spaces, portable fire extinguisher(s) sized in accordance with 5-2-4/1.1 and which can be
discharged through a port in the boundary of the lockers may be accepted. The required portable fire
extinguishers are to be stowed adjacent to the port. Alternatively, a port or hose connection may be provided
for this purpose to facilitate the use of water from the fire main.

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13 Spaces Containing Equipment with Oil Filled Capacitors (2014)

Spaces containing equipment with flammable oil filled capacitors are to be provided with any one of the
following fixed fire extinguishing systems:
i) A gas system complying with the provisions of 5-2-3/3; or
ii) Other approved fire extinguishing system suitable for the equipment voltage hazard.

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PART Section 4: Portable Fire Fighting Systems

5
CHAPTER 2 Active Fire Protection Systems and Equipment

SECTION 4 Portable Fire Fighting Systems

1 Portable Fire Extinguishers and Sand

1.1 Extinguishers (2012)

As a minimum, portable and semi-portable extinguishers are to be provided in the quantities and locations
indicated in 5-2-4/Table 1 and 5-2-4/Table 2. In all cases, the selection of the fire extinguishing medium is
to be based on the fire hazard for the space protected. The fire extinguishers are to be visible and readily
accessible.

1.3 Sand
On self-propelled units fitted with main or auxiliary oil-fired boilers, each firing space is to be provided
with a receptacle containing at least 0.28 m3 (10 ft3) of sand, sawdust impregnated with soda or other dry
material suitable for extinguishing oil fires. Alternatively, an approved portable extinguisher may be substituted
therefore.

3 Fire-Fighters’ Outfit (1993)

3.1 Number (2017)

At least two fire-fighters’ outfits, each with portable instruments for measuring oxygen and flammable vapor
concentrations acceptable of the Administration, consisting of a breathing apparatus, a lifeline, a safety lamp,
an axe, nonconductive boots and gloves, a rigid helmet and protective clothing complying with the requirements
of this paragraph are to be kept ready for use in an accessible location that is permanently and clearly marked.
They are to be stored in two or more widely separated positions so that a fire in one location would not block
access to other outfits.

3.3 Breathing Apparatus

The breathing apparatus is to be of an approved type and may be one of the following:
i) A smoke helmet or smoke mask with a suitable air pump and a length of air hose sufficient to reach
from the open deck, well clear of hatch or doorway, to any part of below deck spaces or machinery
spaces. If, in order to comply with this requirement, an air hose exceeding 36 m (120 ft) in length
would be necessary, a self-contained breathing apparatus is to be substituted or provided in addition.
ii) (2016) A self-contained breathing apparatus which is capable of functioning for a period of at least 30
minutes. Other periods of time will be specially considered. At least two spare charges are to be carried
for each required breathing apparatus carried onboard. Units that are equipped with suitably located
means for fully recharging the air cylinders free from contamination need carry only one spare
charge for each required breathing apparatus.

3.5 Recharging of Air Cylinders (2012)

The apparatus for recharging air cylinders, if provided, is to have its power supplied from the emergency
supply or be independently diesel-powered, or be so constructed or equipped that the air cylinders may be
used immediately after recharging.

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Part 5 Fire and Safety – Measures and Features
Chapter 2 Active Fire Protection Systems and Equipment
Section 4 Portable Fire Fighting Systems 5-2-4

The apparatus is to be suitably located in a sheltered space above main deck level on the unit.
Intakes for air compressors are to draw from a source of clean air. The air is to be filtered after compression
to eliminate compressor oil contamination.
The recharging capacity is to meet the requirements of SOLAS regulation II-2/10.10.2.6.

3.7 Lifeline
Each breathing apparatus is to have attached to its belt or harness, by means of a snap-hook, a fireproof
lifeline of sufficient length and strength.

3.9 Safety Lamp and Axe

A safety lamp (hand lantern) of an approved type and an axe are to be provided. Such safety lamps are to
be electric and are to have a minimum burning period of three hours.

3.11 Boots and Gloves

The boots and gloves are to be made of rubber or other electrically nonconductive material.

3.13 Helmet
A rigid helmet is to be supplied which will provide effective protection against impact.

3.15 Protective Clothing

The protective clothing is to be made of material that will protect the skin from the heat of fire and burns
from scalding steam. The outer surface is to be water resistant.

3.17 Two-way Portable Radiotelephone (2017)

A minimum of two two-way portable radiotelephone apparatus for each fire party for fire-fighter's
communication are to be carried on board. Those two-way portable radiotelephone apparatus are be of an
explosion-proof type or intrinsically safe.

TABLE 1
Classification of Portable and Semi-portable Extinguishers (2012)
Fire extinguishers are designated by types as follows: A, for fires in combustible materials such as wood; B, for
fires in flammable liquids and greases; C, for fires in electrical equipment.
Fire extinguishers are designated by size where size II is the smallest and size V is the largest. Size II is a hand
portable extinguisher, and sizes III, IV, and V are semi-portable extinguishers.

Classification Water, liters Foam, liters Carbon Dioxide, Dry Chemical, Wet Chemical,
Type Size (U.S. gallons) (U.S. gallons) kg (lb) kg (lb) liters (U.S.
gallons)
A II 9 (2.5) 9 (2.5) — 5 (11) (2) 9 (2.5)
B II — 9 (2.5) 5 (11) 5 (11) —
B III — 45 (12) 15.8 (35) 9.0 (20) —
B IV — 76 (20) 22.5 (50) 22.5 (50) —
B V — 152 (40) 45 (100) (1) 22.5 (50) (1) —
C II — — 5 (11) 5 (11) —
C III — — 15.8 (35) 9.0 (20) —
C IV — — 22.5 (50) 13.5 (30) —
F or K II — — — — 9 (2.5)
Notes:
1 For outside use, double the quantity of agent that must be carried.
2 Must be specifically approved as type A, B, or C extinguisher.

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Part 5 Fire and Safety – Measures and Features
Chapter 2 Active Fire Protection Systems and Equipment
Section 4 Portable Fire Fighting Systems 5-2-4

TABLE 2
Hand Portable Fire Extinguishers and Semi-portable Fire-Extinguishing
Systems (2018)
Space Classification* Quantity and Location
Accommodation Spaces
Cabins, lavatories, offices, pantries with no
— None required.
cooking appliances, and similar spaces.
Public spaces A-II 1 for each 250 m2 (2,691 ft2) or fraction thereof
Stairway and elevator enclosure — None required.
Travel distance to an extinguisher not to exceed 25 m
Corridors A-II
(82 ft) within each deck (May be located in stairways)
Hospital A-II 1 required.
Service Spaces
1 for each 250 m2 (2,691 ft2) or fraction thereof
B-II located in vicinity of exits, either inside or outside
Galleys the spaces (see Note 2).
F-II or K-II 1 additional for galleys with deep fat fryers
Pantries with cooking appliances and laundry 1 for each 250 m2 (2,691 ft2) or fraction thereof
A-II or B-II
drying rooms suitable for hazards involved.
Paint and lamp rooms B-II 1 outside each room in vicinity of exit. (See Note 2)
1 for each 250 m2 (2,691 ft2) or fraction thereof
Lockers and storerooms (deck area of 4 m2 or
B-II located in vicinity of exits, either inside or outside
more)
the spaces. (See Note 2)
Small lockers and storerooms (deck area less
— None required.
than 4 m2)
Workshops (not part of machinery spaces,
B-II 1 outside each space in vicinity of an exit. (See Note 2)
galley) and similar spaces
Control Stations
2 near the exit; 1 only if less than 50 m2 (538 ft2).
Wheelhouse A-II or C-II
(See Note 1)
Control rooms (other than Wheelhouse) A-II or C-II 1 required
Radio room C-II 1 outside the space in vicinity of exit. (See Note 2)
Machinery Spaces
(2018) Central control station for propulsion 1 required; when main switchboards are arranged in
machinery/Space containing the controls for the A-II and/or C-II central control station, 1 additional suitable for
main source of electrical power electrical fires
2 required in each space, in addition to the required
Machinery spaces of Category A B-II
for the machinery contained.
2 required in each space (1 at each entrance (see Note
(2018) Machinery spaces of Category A which
B-II 3)) in addition to the required for the machinery
are periodically unattended
contained.
Spaces containing oil-fired boilers, either main
B-V 1 required in each space.
or auxiliary, or their fuel units
Internal combustion engines or gas turbines 1 for each 750 kW (1000 hp) but not less than 2 nor
B-II
with total power output not less than 750 kW more than 6 in each space.
(1000 hp). B-III 1 required in each space.
Internal combustion engines or gas turbines with 1 outside the space containing engines or turbines in
B-II
total power output less than 750 kW (1000 hp). vicinity of exit. (See Note 2)
Electric generators, propulsion motors, thrusters
C-II 1 for each motor or generator.
that do not have enclosed ventilating system.
Electric generators, propulsion motors, thrusters
— None required.
that have enclosed ventilating systems.

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Part 5 Fire and Safety – Measures and Features
Chapter 2 Active Fire Protection Systems and Equipment
Section 4 Portable Fire Fighting Systems 5-2-4

TABLE 2 (continued)
Hand Portable Fire Extinguishers and Semi-portable Fire-Extinguishing
Systems (2018)
Space Classification* Quantity and Location
Machinery Spaces (cont’d)
2 required in the vicinity of the switchboards.
Main switchboards C-II
(See Note 2)
1 outside the space containing motors or generators
Electric emergency motors or generators C-II
in vicinity of exit. (See Note 2)
Steam driven auxiliary machinery — None required.
Enclosed space with oil-fired inert gas
B-II 2 required in each space.
generators, incinerators and waste disposal units
Separately enclosed room with fuel oil purifiers — None required.
Workshops forming part of propulsion
B-II or C-II 1 required in each space.
machinery spaces and other machinery spaces
Trunks to machinery spaces — None required.
Fuel tanks — None required.
Miscellaneous Areas
Open decks — None required.
Lifeboat embarkation and lowering stations and
— None required.
external escape routes
Drill floor C-II 2 required, one at each exit.
Mud pump room C-II 1 required.
1 for each enclosed space (travel distance to an
Mud pits and mud processing areas B-II extinguisher not to exceed 10 m (33 ft) for open
space)
Cranes with electric motors/hydraulics — None required.
2 required, one in cab and one at exterior of engine
Cranes with internal combustion engines B-II
compartment in vicinity of exit. (See Note 2)
Helicopter landing decks (See 5-2-3/9.3)
Helicopter fueling facilities (See 5-2-3/9.3)
Notes:
1 One of which must be placed inside. If chartroom is adjacent to wheelhouse and with direct access from it, no
additional fire extinguisher will be required for the chartroom.
2 Vicinity is intended to mean within 1 m (3 ft)
3 (2018) A portable extinguisher provided for that space may be located outside near the entrance to that space. A
portable fire extinguisher placed outside near the entrance to that space may also be considered as satisfying the
provisions for the space in which it is located.
* See 5-2-4/Table 1.

ABS RULES FOR BUILDING AND CLASSING MOBILE OFFSHORE DRILLING UNITS . 2018 35
PART Section 5: Fire and Gas Detection

5
CHAPTER 2 Active Fire Protection Systems and Equipment

SECTION 5 Fire and Gas Detection

1 Other Fire Protection Requirements

1.1 Fire Detection and Alarm Systems (2013)

1.1.1 General
1.1.1(a) Application. Spaces having a fire risk, are to be provided with an automatic fire detection
and alarm system.
1.1.1(b) Selection of Detectors. In selecting the type of detectors, the following features are to be
taken into account:
i) Capability to detect fire at the incipient stage
ii) Ability to avoid spurious alarm and trips, and
iii) Suitability to the located environment
1.1.1(c) Fire Detection Indicating Board Location. The fire detection main indicator board is to
be at a manned control station and is to be clearly to indicate where fire has been detected.
1.1.2 Machinery Spaces (2018)
1.1.2(a) Unattended Machinery Spaces. Fire detectors are to be fitted in normally unattended
machinery spaces. Detection systems using only thermal detectors, in general, are not to be permitted.
1.1.2(b) Emergency Generator Spaces. Where the emergency diesel generator is 375 kW (500 hp)
and above, its space is to be treated as a Category A machinery space in accordance with 2009
MODU Code Regulation 1.3.34. Accordingly, the fire detection for the emergency diesel generator
space is to comply with the FSS Code Chapter 9, par. 2.4.1.2 (i.e., the fire detection loop serving
the EDG space cannot be combined with that of another Category A machinery space, or control
station, or a service space, or an accommodation space).
Connection with the section of a machinery space other than Category A may be considered
provided all other requirements of FSS Code Chapter 9, as applicable, are met.
1.1.3 Accommodation and Service Spaces
An automatic fire detection and alarm system is to be provided in all accommodation and service
spaces.
Accommodation space is to be fitted with smoke detectors. Thermal detectors are to be fitted in
galleys.
1.1.4 Electrical Rooms and Control Stations
Smoke detectors are to be provided in all electrical rooms and control stations.
1.1.5 Drilling and Mud Processing Areas
Flame or thermal detectors are to be installed in open drilling and/or mud processing areas.
Smoke detectors may be used in enclosed mud processing areas.

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Part 5 Fire and Safety – Measures and Features
Chapter 2 Active Fire Protection Systems and Equipment
Section 5 Fire and Gas Detection 5-2-5

1.1.6 Manually Operated Alarm System

Sufficient manual fire alarm stations are to be installed throughout the accommodation spaces,
service spaces, and control stations. One manually operated call point is to be located at each exit.
Manually operated call points are to be readily accessible in the corridors of each deck such that
no part of the corridor is more than 20 m (66 ft) from a manually operated call point.
Measures are to be taken to prevent inadvertent operation of the manual call alarm system.

1.3 General Alarm

1.3.1 Overview
A general alarm system is to be provided and so installed as to be clearly perceptible in all parts of
the unit. Alarm signal devices are to be provided which will produce a distinctive and strong note.
The signals used should be limited to: general emergency, toxic gas (hydrogen sulfide), combustible
gas, fire alarm, and abandon unit signals.
The signals given over the general alarm system should be supplemented by instructions over the
public address system.
1.3.2 Locations
At least in the following spaces, the general alarm is to be capable of being operated:
i) Main control station
ii) Drilling console
iii) Navigating bridge (if any), and
iv) Fire control station (if any)

1.5 Public Address (2013)

See 4-3-2/15.9.

1.7 Mud Tank Level Alarm

A suitable audible and visual alarm to indicate significant increase or decrease in the level of the contents of
the active mud tanks is to be provided, both at the control station for drilling operations and at the mud tank.

1.9 Ventilation System Alarms

See 4-3-6/7 and 4-3-3/9.3.3.

3 Gas Detection and Alarm Systems (2013)

Fixed automatic combustible gas detection and alarm systems are to be provided for the following areas:
i) Cellar deck
ii) Drill floor
iii) Mud pit area
iv) Shale shaker area
v) Enclosed spaces containing open components of the mud circulation system from the bell nipple
to the mud pits.
vi) Ventilation intakes of enclosed machinery spaces contiguous to hazardous areas and containing
internal combustion engines and boilers, and
vii) Ventilation intakes and near other openings of accommodation spaces

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Part 5 Fire and Safety – Measures and Features
Chapter 2 Active Fire Protection Systems and Equipment
Section 5 Fire and Gas Detection 5-2-5

The gas detectors are to be connected to an audible and visual alarm system with indicators on the drill
floor and at the required emergency control stations (See 5-3-1/7). The alarm system is to clearly indicate
the location and concentration of the gas hazard. The combustible gas detectors are to alarm at not more
than 25% and at 60% of the lower explosive limit (LEL).
In addition to the fixed automatic gas detection system, two portable combustible gas detectors are to be
provided on the unit.

5 Hydrogen Sulfide Detection and Alarm (2013)

5.1 Areas for Protection

A fixed automatic hydrogen sulfide gas detection and alarm system are to be provided for the following areas:
i) Drill area
ii) Mud processing area, and
iii) Well test area

5.3 Alarms (2018)

The detectors are to be connected to an audible and visual alarm system with indicators in main control
room. The system is clearly to indicate where gas has been detected.
Low level alarm set at 10 ppm and high level alarm set not higher than 300 ppm are to be provided. The high
level alarm is to activate the toxic gas (hydrogen sulfide) alarm in the general alarm system (see 5-2-5/1.3).
If the low level alarm at the main control point is unanswered within 2 minutes, the toxic gas (hydrogen
sulfide) alarm and the helideck status light is to be automatically activated.

5.5 Portable Hydrogen Sulfide Gas Detectors

At least two portable hydrogen sulfide gas monitoring devices should be provided on the unit.

7 Respiratory Protection Equipment for Hydrogen Sulfide (2013)

7.1 Self-contained Breathing Apparatus (SCBA)

A self-contained breathing apparatus (SCBA) positive-pressure/pressure-demand breathing equipment
with full-face piece and rated for a minimum of 30 minutes is to be provided for each person in working
areas where hydrogen sulfide may be encountered, and each person in other areas is to be provided with a
SCBA rated for a minimum of 15 minutes, or

7.3 Air Line Breathing Equipment

7.3.1 Details
Positive-pressure/pressure-demand air line breathing equipment coupled with a SCBA-equipped
low pressure warning alarm and rated for a minimum of 15 minutes is to be provided for each
person on board the unit.
7.3.2 Locations
Breathing air supply line stations are to be provided at least in the following areas:
i) Living quarters
ii) Muster/evacuation area
iii) Drilling areas
iv) Mud processing areas, and
v) Other working areas

38 ABS RULES FOR BUILDING AND CLASSING MOBILE OFFSHORE DRILLING UNITS . 2018
PART Chapter 3: Outfitting

5
CHAPTER 3 Outfitting

CONTENTS
SECTION 1 General .................................................................................................. 41
1 Means of Escape .............................................................................. 41
3 Means of Access and Egress ........................................................... 42
3.1 General.......................................................................................... 42
3.3 Means of Escape and Access for Helicopter Decks ...................... 42
5 Guards and Rails .............................................................................. 43
5.1 Floor Deck Areas and Openings ................................................... 43
5.3 Helicopter Landing Deck ............................................................... 43
7 Emergency Control Stations ............................................................. 43
9 Arrangements in Machinery Space ................................................... 43
9.1 Ventilating Fans and Openings ..................................................... 43
9.3 Other Auxiliaries ............................................................................ 44
9.5 Oil Tank Suction Pipes .................................................................. 44
9.7 Oil Fuel Unit................................................................................... 44
9.9 Floor Plating in Machinery Spaces of Category A ......................... 44
11 Segregation of Fuel Oil Purifiers ....................................................... 44
13 Rotary Table Area ............................................................................. 44
15 Fire Precautions for Machinery Spaces ............................................ 45

APPENDIX 1 Fiber Reinforced Plastic (FRP) Gratings ............................................ 46

1 General ............................................................................................. 46
3 FRP Grating Material Systems ......................................................... 46
5 Fire Test Requirements .................................................................... 46
5.1 Structural Fire Integrity .................................................................. 46
5.3 Flame Spread ................................................................................ 47
5.5 Smoke Generation ........................................................................ 47
7 Structural Fire Integrity Test Procedures .......................................... 47
9 Structural Fire Integrity Matrix ........................................................... 47
11 Other Authorized Uses...................................................................... 48

TABLE 1 Structural Fire Integrity Matrix ................................................. 47

ABS RULES FOR BUILDING AND CLASSING MOBILE OFFSHORE DRILLING UNITS . 2018 39
 APPENDIX 2 Fiber Reinforced Plastic (FRP) Guard Railings.................................. 49
1 General .............................................................................................49
3 FRP Guard Railing Material Systems ...............................................49
5 Fire Test Requirements ....................................................................49
5.1 Fire Retardance ............................................................................. 49
5.3 Flame Spread ................................................................................ 49
5.5 Self Extinguishing .......................................................................... 50
7 Application of FRP Guard Railing .....................................................50
9 Other Requirements..........................................................................50

TABLE 1 Application of FRP Guard Railing ...........................................50

40 ABS RULES FOR BUILDING AND CLASSING MOBILE OFFSHORE DRILLING UNITS . 2018
PART Section 1: General

5
CHAPTER 3 Outfitting

SECTION 1 General

1 Means of Escape (1993)

1.1
The following requirements are to apply to accommodation spaces, service spaces and control stations:
1.1.1
In every general area that is likely to be regularly manned or in which personnel are accommodated,
at least two separate escape routes are to be provided, situated as far apart as practicable, to allow
ready means of escape to the open decks and/or embarkation stations. Exceptionally, one means of
escape may be considered, taking into account the nature and location of spaces and the number of
persons who might normally be accommodated or employed there.
1.1.2
Stairways are to normally be used for means of vertical escape. However, a vertical ladder may be
used for one of the means of escape from machinery spaces when the installation of a stairway is
shown to be impracticable.
1.1.3
Every escape route should be readily accessible and unobstructed and all exit doors along the route
are to be readily operable from both sides. Dead-end corridors exceeding 7 m (23 ft) in length are
not permitted.
1.1.4 (2012)
In addition to the emergency lighting, the means of escape in accommodation areas, including
stairways and exits, are to be marked by lighting or photoluminescent strip indicators placed not more
than 300 mm above the deck at all points of the escape route, including angles and intersections.
The marking is to enable personnel to identify the routes of escape and readily identify the escape
exits. If electric illumination is used, it is to be supplied by the emergency source of power and it
is to be so arranged that the failure of any single light or cut in a lighting strip will not result in the
marking being ineffective. Additionally, escape route signs and fire equipment location markings
are to be of photoluminescent material or marked by lighting. The lighting or photoluminescent
equipment are to be evaluated, tested and applied in accordance with the International Code for
Fire Safety Systems (Resolution MSC.98(73)) (FSS Code).

1.3 (2014)
Two means of escape are to be provided from every machinery space of Category A by either of the following:
1.3.1
Two sets of steel ladders as widely separated as practicable leading to doors in the upper part of
the space similarly separated and from which access is provided to the open deck. One of these
ladders is to be located within a protected enclosure that satisfies 5-1-1/Tables 1 and 2, category
(4), from the lower part of the space it serves to a safe position outside the space. Self-closing fire
doors of the same fire integrity standards are to be fitted in the enclosure. The ladder is to be fixed
in such a way that heat is not transferred into the enclosure through non-insulated fixing points.
The enclosure is to have minimum internal dimensions of at least 800 mm by 800 mm, and is to be
provided with emergency lighting.

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Part 5 Fire and Safety – Measures and Features
Chapter 3 Outfitting
Section 1 General 5-3-1

1.3.2
One steel ladder leading to a door in the upper part of the space from which access is provided to
the open deck. Additionally, in the lower part of the space and in a position well separated from
the ladder referred to, a steel door capable of being operated from each side is to be provided with
access to a safe escape route from the lower part of the space to the open deck.
The minimum width between stringers of the above mentioned ladders, or of any other vertical or inclined
ladder fitted to provide means of escape within and from machinery spaces, is not be less than 600 mm.

1.5
From machinery spaces other than those of Category A, escape routes are to be provided having regard to
the nature and location of the space and whether persons are normally employed in that space.

1.7
Elevators are not to be considered as forming one of the required means of escape.

1.9
At least one escape route from the superstructure and deckhouses to the survival craft embarkation area is
to be protected against radiation effects of a drill floor area fire as far as practicable

1.11 (2012)
Stairways and corridors used as a means of escape are to be not less than 700 mm (27.6 in.) in clear width
and are to have a handrail on one side. Stairways and corridors with a clear width of 1800 mm (70.9 in.)
and over are to have handrails on both sides. Clear width is considered the distance between the handrail
and the bulkhead on the other side or between the handrails. The angle of inclination of stairways is to be,
in general, 45°, but not greater than 50°, and in machinery spaces and small spaces not more than 60°.
Doorways which give access to a stairway are to be of the same size as the stairway.

1.13 (2012)
All materials that comprise the escape routes and muster stations are to be of steel or equivalent material
which would not be rendered ineffective by heat. Fiber Reinforced Plastic (FRP) gratings may be considered,
provided all conditions listed in Appendix 5-3-A1 are fully met and are accepted by the Flag Administration.

3 Means of Access and Egress (2018)

3.1 General
At least two means of escape from the unit are to be provided. They are to consist of fixed stairways or
fixed ladders constructed of steel and extending from the unit to the surface of the water. In the case of self-
elevating units, the means of escape will be specially considered. Sufficient personnel landings are to be
provided on each unit to assure safe access and egress. When, due to special construction, personnel landings
are not feasible, suitable transfer facilities to provide safe access and egress are to be installed.

3.3 Means of Escape and Access for Helicopter Decks

The helicopter deck is to be provided with both a main and an emergency means of escape and access for
fire fighting and rescue personnel. These means are to be located as far apart from each other as is practicable
and preferably on opposite sides of the helicopter deck.
Aluminum access/egress platforms and stairways leading to and from the helideck are acceptable provided
the following conditions are satisfied:
i) Conditions in Ch. II-2/Reg. 18.3.2 of IMO SOLAS or Ch 9.16.2 of IMO MODU Code, as applicable,
are to be met.
ii) Acceptance to be obtained from the flag Administration.

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Part 5 Fire and Safety – Measures and Features
Chapter 3 Outfitting
Section 1 General 5-3-1

iii) The firefighting equipment, which includes the hose reel, portable fire extinguishers, fixed foam
system, is to provide coverage for the access/egress platforms and stairways. The capacity of the
fixed foam system is to be increased to include the additional areas of protection for the aluminum
access/egress platforms and stairways.
iv) Where the helideck is also used as a firefighting station, the aluminum access/egress platforms and
stairways are to meet the L3 fire integrity test, or equivalent as per 5-3-A1/Table 1.
v) Where alternative means of fire protection (such as deluge system) are provided (typically along
stairways or access under the helideck), and the arrangement and locations of the firefighting
equipment, required in 5-3-1/3.2i) above are also available at or cover the access/egress route, the
L3 performance test will not be necessary.
vi) Where the helideck is fitted with a refueling station, there is to be sufficient distance from the
refueling station to at least one of the stairs, such that the aluminum stairs are not impacted by the
fire at the refueling station.
In case of a fire outside the helideck area, access platforms and stairways are not to be considered part of
an escape route.

5 Guards and Rails

5.1 Floor Deck Areas and Openings (2003)

Except for helicopter landing decks, which are provided for in 5-3-1/5.3, and areas not normally occupied,
the unprotected perimeter of all floor or deck areas and openings is to be protected with efficient guard
rails or bulwarks. The height of the bulwarks or guard rails is to be at least 1 m (39.5 in.) from the deck,
except that where this height would interfere with the normal operation of the unit, a lesser height may be
considered if adequate protection is provided. Where approval of a lesser height is requested, justifying
information is to be submitted, such as arrangements provided to prevent personnel going over the guard
rails or bulwarks. The opening below the lowest course of the guard rails is not to exceed 230 mm (9 in.).
The other courses are not to have more than 380 mm (15 in.) clear opening. In the case of units with
rounded gunwales, the guard rail supports are to be placed on the flat of the deck.

5.3 Helicopter Landing Deck

The unprotected perimeter of the helicopter landing deck is to be provided with safety netting or equivalent.

7 Emergency Control Stations (2017)

At least two emergency control stations are to be provided. One of the stations is to be located near the
drilling console and the other station is to be at a suitable manned location outside of the hazardous areas.
The control stations are to be provided with the following.
• Manually operated contact makers for actuating the general alarm system.
• An efficient means of communication between these stations and all locations vital to the safety of the unit.
• Emergency shut-down facilities. (See 4-3-5/7.1.1)
• Gas Detection and Alarm Panel (5-2-5/3)

9 Arrangements in Machinery Space

9.1 Ventilating Fans and Openings (2011)

9.1.1 General
Means are to be provided for stopping ventilating fans serving machinery spaces and for closing
all doorways, ventilators, annular spaces around funnels and other openings to such spaces. These
means are to be capable of being manually operated from outside of such spaces in case of fire.

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Part 5 Fire and Safety – Measures and Features
Chapter 3 Outfitting
Section 1 General 5-3-1

9.1.2 Release of Smoke from Machinery Space

Suitable arrangements are to be made to permit the release of smoke, in the event of fire, from the
machinery space of Category A. The normal ventilation may be acceptable for this purpose. The
means of control is to be provided for permitting the release of smoke and such control is to be
located outside the space concerned so that they will not be rendered inaccessible in the event of
fire in the space they serve. See also 4-3-2/5.3.12 and 4-3-3/5.17.1

9.3 Other Auxiliaries (2009)

Machinery driving forced and induced draft fans, electric motor pressurization fans, oil fuel transfer pumps,
oil fuel unit pumps and other similar fuel pumps are to be fitted with remote controls situated outside of the
space concerned so that they may be manually stopped in the event of a fire arising in the space in which
they are located. See 4-3-2/19.1.2.
In addition to the remote shutdowns required above, a means to shut down the equipment is to be provided
within the space itself.

9.5 Oil Tank Suction Pipes

Every fuel oil suction pipe from a storage, settling or daily service tank which emanates at such a level that
it will be subjected to a static head of oil from the tank is to be fitted with a positive shutoff valve capable
of being closed manually from a readily accessible location outside of the space in which the valve is located.

9.7 Oil Fuel Unit (1995)

Oil fuel unit is any equipment, such as pumps, filters and heaters, used for the preparation and delivery of
fuel oil to oil-fired boilers (including incinerators and inert gas generators), internal-combustion engines or
gas turbines at a pressure of more than 1.8 bar (1.8 kgf/cm2, 26 psi).

9.9 Floor Plating in Machinery Spaces of Category A (2018)

The floor plating of normal passageways in machinery spaces of category A is to be made of steel.

11 Segregation of Fuel Oil Purifiers (1997)

Fuel oil purifiers for heated oil are to be placed in a separate room or rooms, enclosed by steel bulkheads
extending from deck to deck and provided with self-closing doors. In addition, the room(s) is to be provided
with the following: (See also 5-3-1/9.1 and 5-3-1/9.3)
i) Independent mechanical ventilation or a ventilation arrangement which can be isolated from the
machinery space ventilation
ii) Fire detection system
iii) Fixed fire extinguishing system capable of activation from outside the room. The extinguishing
system is to be separate for the room but may be part of the main fire extinguishing system for the
machinery space.
iv) Means of closing ventilation openings from a position close to where the fire extinguishing system
is activated
If it is impracticable to locate the fuel oil purifiers in a separate room, special consideration will be given in
regard to location, containment of possible leakage, shielding and ventilation. In such cases, a local fixed
fire extinguishing system is to be provided and arranged to be activated automatically, where permitted, or
manually from the machinery control position or from another suitable location. If automatic release is
provided, additional manual release is also to be arranged.

13 Rotary Table Area

The area adjacent to the rotary table is to be free of openings through which gases or water can enter the
hull structure. Any such openings that are necessary are to be equipped with quick-acting closing devices.

44 ABS RULES FOR BUILDING AND CLASSING MOBILE OFFSHORE DRILLING UNITS . 2018
Part 5 Fire and Safety – Measures and Features
Chapter 3 Outfitting
Section 1 General 5-3-1

15 Fire Precautions for Machinery Spaces (1996)

Installation in machinery spaces which contain fired boilers, internal combustion engines, oil purifiers and
similar equipment are to comply with the following:
i) The surfaces of all internal combustion engines, gas turbines, boilers, exhaust pipes and other exposed
parts which may be heated to a temperature in excess of 220°C (428°F) and may be exposed to
flammable liquids are to be insulated. Where insulation is oil absorbing and exposed to penetration
of oil, this insulation is to be encased in sheet metal or an equivalent impervious sheet.
ii) Drip trays for collecting oil, as required in 4-2-1/11.33, are to be fitted below pumps, burners, tanks,
etc. They are to be of suitable height and provided with suitable drainage to a collecting tank
incorporating a high level alarm.
iii) Hydraulic pumps, actuators, motors and accessories are to be suitable for the intended duty, compatible
with the working fluid and are to be designed to operate safely at full-power conditions. In general,
the hydraulic fluid is to be nonflammable or have a flash point above 157°C (315°F).
iv) For unmanned machinery spaces, fuel oil heaters, purifiers, pumps and filters are to be shielded or
grouped in a special room or location ventilated by suction.

ABS RULES FOR BUILDING AND CLASSING MOBILE OFFSHORE DRILLING UNITS . 2018 45
PART Appendix 1: Fiber Reinforced Plastic (FRP) Gratings

5
CHAPTER 3 Outfitting

APPENDIX 1 Fiber Reinforced Plastic (FRP) Gratings (2013)

1 General

1.1 (2018)
FRP gratings may be used in other machinery spaces, cargo areas, and on-deck areas. FRP gratings are not
accepted in accommodation, service, control spaces, and areas where smoke and toxicity is a concern. The
floor plating and gratings in Category A machinery spaces is to be made of steel. Refer to 5-3-A1/Table 1.
FRP gratings are to meet the performance requirements of and are to be tested in accordance with ASTM
F3059-15, Standard Specification for Fiber-Reinforced Polymer (FRP) Gratings Used in Marine Construction
and Shipbuilding.

1.3
Changes in either the type, amount, and/or architecture, of either the reinforcement materials, resin matrix,
coatings, or manufacturing processes shall require separate testing in accordance with the procedures below.
Manufacturers should provide evidence, such as enrollment in a follow-up program, that the FRP gratings
being installed are the same as those which were tested and approved.

3 FRP Grating Material Systems

3.1
All fire integrity, flame spread, smoke, and toxicity testing, where required, shall be conducted on each
material system.

5 Fire Test Requirements (2018)

5.1 Structural Fire Integrity

The structural fire integrity requirements are intended for self-supporting personnel platforms or walkways,
and are not intended for grating overlaid on steel decking or used in other applications such as pipe guards,
sea chest screenings, safety guards, etc.
The structural fire integrity matrix in 5-3-A1/Table 1 establishes the structural fire integrity characteristics that
FRP gratings should possess, based on location and service. Where a specific application satisfies more
than one block in the matrix, the highest level of fire integrity is required. The test procedures required to
qualify FRP gratings to one of four levels are described in 5-3-A1/7. The location and service of the FRP
gratings are to be determined on the basis of the following considerations for each of the four performance
levels:
5.1.1 Level 1 (L1)
FRP gratings meeting the L1 performance criteria are intended to be satisfactory for use in escape
routes or access for firefighting, emergency operation or rescue, after having been exposed to a
significant hydrocarbon or cellulosic fire incident. In addition, they are also acceptable for the
services and functions described for levels L2 and L3.

46 ABS RULES FOR BUILDING AND CLASSING MOBILE OFFSHORE DRILLING UNITS . 2018
Part 5 Fire and Safety – Measures and Features
Chapter 3 Outfitting
Appendix 1 Fiber Reinforced Plastic (FRP) Gratings 5-3-A1

5.1.2 Level 2 (L2)

FRP gratings meeting the L2 performance criteria are intended to be satisfactory for use in open
deck areas where groups of people are likely to assemble, such as temporary safe refuge or lifeboat
embarkation areas. In addition, they are also acceptable for the services and functions described
for level L3.
5.1.3 Level 3 (L3)
FRP gratings meeting the L3 performance criteria are intended to be satisfactory for use in egress
routes and any areas that may require access for firefighting, rescue or emergency operations
during exposure to or shortly after exposure to a transitory hydrocarbon or cellulosic fire.
5.1.4 Level 0 (L0)
L0 FRP gratings are to be tested in accordance with ASTM E84 with a flame spread index not to
exceed 20 and a smoke developed index not to exceed 450. L0 FRP gratings have no fire integrity.
L0 FRP gratings may be used for personnel walkways, catwalks, ladders, platforms, or access
areas in cargo holds and tanks.

5.3 Flame Spread

All FRP gratings are to have low flame spread characteristics as determined by the following test procedure:
5.3.1
Tested to ASTM E84 with a flame spread rating not to exceed 20.

5.5 Smoke Generation

All FRP gratings are to have low smoke characteristics as determined by the following test procedure:
5.5.1
Tested to ASTM E84 with a smoke developed index limit not to exceed 450.

7 Structural Fire Integrity Test Procedures (2018)

Structural fire integrity tests are to be in accordance with ASTM F3059-15 according to the structural fire
integrity performance levels (L1, L2, L3, L0).

9 Structural Fire Integrity Matrix

TABLE 1
Structural Fire Integrity Matrix (2018)
Location Service Fire Integrity
Machinery Spaces of Category A(1) Steel Grating -
Walkways or areas which may be used for escape, or access for
L1(2)
firefighting, emergency operation or rescue
Other Machinery Spaces
Personnel walkways, catwalks, ladders, platforms or access areas other
L3
than those described above
Cargo Pump Rooms All personnel walkways, catwalks, ladders, platforms or access areas L1
Walkways or areas which may be used for escape, or access for
L1
firefighting, emergency operation or rescue
Cargo Holds
Personnel walkways, catwalks, ladders, platforms or access areas other
L0
than those described above
Cargo Tanks All personnel walkways, catwalks, ladders, platforms or access areas L0(3)
Fuel Oil Tanks All personnel walkways, catwalks, ladders, platforms or access areas L0(3)
Ballast Water Tanks All personnel walkways, catwalks, ladders, platforms or access areas L0(4)
Cofferdams, void spaces, double
All personnel walkways, catwalks, ladders, platforms or access areas L0(4)
bottoms, pipe tunnels, etc.

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Part 5 Fire and Safety – Measures and Features
Chapter 3 Outfitting
Appendix 1 Fiber Reinforced Plastic (FRP) Gratings 5-3-A1

TABLE 1 (continued)
Structural Fire Integrity Matrix (2018)
Location Service Fire Integrity
Accommodation, service, and
All personnel walkways, catwalks, ladders, platforms or access areas Not permitted
control spaces
Lifeboat embarkation or temporary
safe refuge stations in open deck All personnel walkways, catwalks, ladders, platforms or access areas L2
areas
Operational areas and access routes for deck foam firefighting systems
L2
on tank vessels
Walkways or areas which may be used for escape, or access for
firefighting systems and AFFF hose reels, emergency operation, or
L2
rescue on MODUs and production platforms including safe access to
Open Decks or semi-enclosed areas tanker bows
Walkways or areas which may be used for escape, or access for
firefighting, emergency operation or rescue other than those described L3(5)
above
Personnel walkways, catwalks, ladders, platforms or access areas other
L3
than those described above
Notes:
1 (2018) Machinery spaces of category A is as defined in 4-1-1/3.3 and 5-1-1/3.9.2(6).
2 If the machinery space does not contain any internal combustion machinery, other oil-burning, oil-heating, or
oil-pumping units, fuel oil filling stations, or other potential hydrocarbon fire sources, and has not more than
2.5 kg/m2 of combustible storage, gratings of L3 integrity may be used in lieu of L1.
3 If these spaces are normally entered when underway, gratings of L1 integrity shall be required.
4 If these spaces are normally entered when underway, gratings of L3 integrity shall be required.
5 (2018) Vessels fitted with deck foam or dry powder firefighting systems require gratings of L2 integrity for the
firefighting system operational areas and access routes.

11 Other Authorized Uses (2018)

11.1
The ABS Surveyor may authorize the use of FRP gratings without Main Office approval in applications
where structural fire integrity of the FRP gratings is not a concern, provided they meet the applicable flame
spread and smoke generation requirements set forth in 5-3-A1/5.3 and 5-3-A1/5.5. Applications where the
use of FRP gratings have been authorized in the past, without any structural fire integrity requirements,
include the following:
i) Sea chest coverings;
ii) Small sundeck awnings and supports;
iii) Lifeboat bilge flooring;
iv) Electrical control flooring;
v) Pipe guards on deck, in cargo holds, and in engine rooms;
vi) Removable guards over hawse holes, anchor hawse pipes, and scuppers;
vii) Personnel barriers, such as protection for electrical panels; and
viii) Ship staging and work platforms (Occupational Safety and Health Administration (OSHA)
requirements may also apply).

48 ABS RULES FOR BUILDING AND CLASSING MOBILE OFFSHORE DRILLING UNITS . 2018
PART Appendix 2: Fiber Reinforced Plastic (FRP) Guard Railings

5
CHAPTER 3 Outfitting

APPENDIX 2 Fiber Reinforced Plastic (FRP) Guard Railings

(2016)

1 General

1.1
FRP guard railings are not specifically addressed in the individual vessel regulations. However, the resins
typically used in the manufacture of these guard railings are combustible and heat sensitive; therefore, FRP
guard railings use must be limited based on the requirements discussed below.

1.3
These requirements are not intended to eliminate any other design criteria or requirement pertaining to the
material, construction, or performance of the FRP guard railings in the non-fire condition.

1.5
FRP guard railings are to comply with:
i) Appendix 5-3-A2 of the MODU Rules
ii) Flag Administration requirements
iii) A published standard from an organization recognized by ABS as being acceptable

3 FRP Guard Railing Material Systems

3.1
All flame spread, smoke, and toxicity testing, where required, are to be conducted on each material system.

3.3
Changes in either the type, amount, and/or architecture, of either the reinforcement materials, resin matrix,
coatings, or manufacturing processes shall require separate testing in accordance with the procedures below.
Manufacturers should provide evidence, such as enrollment in a follow-up program, that the FRP guard
railings being installed are the same as those which were tested and approved.

5 Fire Test Requirements

5.1 Fire Retardance

All FRP guard railings are to be fire retardant; this can be demonstrated by testing to ASTM E-84, Standard
Test Method for the Surface Burning Characteristics of Building Materials with a flame spread rating not
to exceed 25, or by meeting the requirements in 5-3-A2/5.3.1 or 5-3-A2/5.3.2 below.

5.3 Flame Spread

All FRP guard railings, except those fitted on open decks and within tanks, cofferdams, void spaces, pipe
tunnels and ducts, should have low flame spread characteristics as determined by one of the following test
procedures:

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Part 5 Fire and Safety – Measures and Features
Chapter 3 Outfitting
Appendix 2 Fiber Reinforced Plastic (FRP) Guard Railings 5-3-A2

5.3.1
Tested to ASTM E-84 with a flame spread rating not to exceed 20; or
5.3.2
Tested to IMO Resolution A.653(16), Recommendation on Improved Fire Test Procedures for Surface
Flammability of Bulkhead, Ceiling and Deck Finish Materials and meeting the criteria for bulkheads,
linings, or ceilings.

5.5 Self Extinguishing

All FRP guard railings should meet the self extinguishing requirement of ASTM D-635.

7 Application of FRP Guard Railing

Suitable locations for FRP guard railings are given in 5-3-A2/Table 1.

TABLE 1
Application of FRP Guard Railing (2016)
Location Service
Holds/Storages Personnel walkways, catwalks, ladders, platforms or access areas,
Open Decks or semi-enclosed areas except where used for escape, or access for firefighting, emergency
not protected by deck foam operation or rescue
firefighting system

9 Other Requirements

9.1
The FRP guard rails are to be fabricated in accordance with a recognized standard, such as ASTM E985,
with adequate strength to withstand the anticipated loads.

9.3
The weathering characteristics of the FRP guard rails should be in compliance with a recognized standard
(for example ASTM D4587, ASTM D4329) for testing resistance to ultraviolet degradation for those exposed
to weather.

50 ABS RULES FOR BUILDING AND CLASSING MOBILE OFFSHORE DRILLING UNITS . 2018