HOT WORK PROCEDURE
TABLE OF CONTENTS
1. PURPOSE................................................................................................................................ 4
2. SCOPE..................................................................................................................................... 4
3. TERMS & DEFINITIONS.......................................................................................................... 4
4. REFERENCES......................................................................................................................... 4
5. RESPONSIBILITIES................................................................................................................ 4
6. PROCEDURE.......................................................................................................................... 5
6.1. Defining Hot Work........................................................................................................... 5
6.2. Hazard of Hot Work........................................................................................................ 6
6.3. Controlling Hot Work....................................................................................................... 7
6.4. Hot Work Implementation............................................................................................... 9
6.5. Requirements................................................................................................................ 11
7. ATTACHMENTS.................................................................................................................... 11
1. PURPOSE
Risks are inherent part of any work. Risks exist in the work itself and/or in the area
adjacent to the work to be carried out. Work permit system is established to control
the risks to manageable level.
2. SCOPE
This procedure provides guideline to project key personnel in implementation of Work
Permit System at any Contractor work places.
3. TERMS & DEFINITIONS
3.1. COMPANY
The organization that gives order to, and receives products from, Contractor
3.2. CONTRACTOR
Organization that receives order from the Company and subcontracts the work
package to Subcontractors
3.3. SUBCONTRACTOR
Organization that receives order from, and gives products to, Contractor
3.4. HSSE
Health, Safety, Security, and Environment
3.5. SUBORGANIZATIONS
Departments / Disciplines / Subcontractors / Other Suborganizations
3.6. COMPANY’S CONTROLLED AREA
Refer to COMPANY’s definition, normally an area where COMPANY’s
operating facilities exist.
4. REFERENCES
4.1. General HSSE Procedure
4.2. OSHA 1910.252 Welding, Cutting and Brazing
4.3. All other applicable regulations
5. RESPONSIBILITIES
5.1. DEPARTMENT MANAGER
Ensure preparation, socialization, maintenance, and continual improvement of
this procedure and its implementation
5.2. HSSE MANAGER
Manage (plan, organize/do, lead, and control) preparation, socialization,
maintenance, and continual improvement of this procedure and its
implementation
5.3. HSSE ENGINEER(S)/OFFICER(S)
Assist HSSE Manager in preparation, socialization, maintenance, and
continual improvement of this procedure and its implementation.
5.4. SUB-ORGANIZATION REPRESENTATIVES
Under HSSE Sub-organization coordination; socialize, maintain, and
continually improve implementation of this procedure/relevant procedure for
their scope.
5.5. OTHER EMPLOYEES
Assist their Sub-organization Representatives in socialization, maintenance, and
continual improvement of implementation of this procedure/relevant procedure for
the project for their scope
5.8. AREA AUTHORITY
Area Authority shall check the work permit to ensure the work will be performed
in an inherently safe method and sequence, by relating the permit to the work
execution procedure as applicable.
Safety personnel shall check the work permit to ensure that preventive
precautionary prerequisites such as JSA, TBM, PPE, fall protection, fire
protection, etc will be adequately provided with the work.
5.9. PERFORMING AUTHORITY
PA shall be responsible to prepare work permit and get approval prior to start the
work, and shall instruct his/her subordinates not to start there before.
5.10.FIRE WATCHER (FW)
A fire watcher is responsible to monitor the work area while fire and gas system are
inhibited for naked flame hot work
5.11. AUTHORIZED GAS TESTER
Authorized gas tester is person nominated by the Contractor to conduct the gas
test. The gas tester must attend gas test course and passed examination.
6. PROCEDURE
6.1. Defining Hot Work
Hot work refers to any task uses (or could create) a flame, spark or other energy
discharge that might in turn ignite a fire or explosion. It is normal practice to
consider two types of hot work:
- High energy – naked flame
- Lower energy – spark potential
5.5.1. Hot work – naked flame
Hot work naked flame is any work with equipment and tools that, when used
in a normal manner, are likely to ignite a flammable or explosive
atmosphere, solid materials, and liquids.
High energy is present in the form of a flame, electric-arc, incandescent
sparks or the equipment has a surface temperature that exceeds 200o C.
Hot work naked flame could involve any of the following activities (note this
list is not exhaustive):
- Naked flames (welding, flame cutting), electrical welding.
- Electrical induction pre-heating, stress relieving or use of high
temperature thermal calibrators (above 200oC), except in authorised
workshops
- Use of portable grinders and abrasive wheels
- Use of flare guns
- Use of heat shrink blowers in hazardous zones
- Use of equipment or work on pipe work vessels contaminated or
potentially contaminated with pyrophoric scale.
5.5.2. Hot work – spark potential
Hot work spark potential is work with equipment and tools that when used in
normal manner or due to errors or malfunctions, may create lower energy
sparks and ignites a flammable atmosphere.
Hot work – spark potential include (note this list is not exhaustive):
- Dry grit/shot blasting in hazardous areas/zones
- Needle gunning and pneumatic chisels in hazardous zones
- Use of battery-operated cameras in hazardous zones
- Use of non-appropriately rated EX equipment in hazardous areas/zones
- Opening live electrical junction boxes in hazardous zones where the
terminals are exposed to atmosphere.
- Use of air or hydraulically powered tools, mechanically capable of
generating a spark in hazardous zones
- Use of electrically powered equipment capable of generating a spark in
hazardous areas
- Work involving explosives in hazardous zones.
- Use of cartridge operated fixing tools in hazardous zones
- Operation of protected portable diesel engines not tied into fire and gas
systems in hazardous and non-hazardous areas
6.2. Hazard of Hot Work
6.2.1. Hazards to personnel
Hot work presents direct hazards to those involved in the task, or working
nearby. Skin/eye burns and electric shock are obvious direct hazards.
A hot surface or a spark can burn skin, either by contact or from radiated
heat. The eyes particularly sensitive to burning, including from light radiation
– “arc eye”
Whilst the direct hazards of hot work are important, the risks from fires and
explosions are typically more significant, especially in operational areas.
6.2.2. Solid/liquid fires
Flames and incandescent sparks can ignite materials such as: wood, paper,
clothing, oil, paint, solvents, etc.
If this happens, flammable liquids and finely divided solids will burn
immediately, such fires are usually easy to observe.
But other solids material may smolder for a time before primary source of
ignitions and smoke become visible.
This is particularly the case in crevices or void spaces, where a spark may
lodge unobserved. Many large-scale fires have arisen from this cause,
because the workplaces was not monitored for long enough after the hot
work ceased.
6.2.3. Gas fire / explosion
Flammable gas and liquids with a flash point below typical ambient
temperature require much less ignition energy than solids.
Thus gases and vapors can be ignited by flames and incandescent sparks
and also by lower-energy sparks, e.g. from electrical equipment, static,
friction, etc.
If the gas or liquid is unconfined, there will be an initial “flash fire”, than
possibly a residual pool or jet fire at the point of release.
If the gas or vapour is confined, for example inside a mostly empty vessel or
tank, there can be an explosion, resulting from rapid pressure build up due
to the flash fire, followed by failure of the container.
An explosion is also result if a large gas or vapour release is ignited well
away from the release point, because the interaction of the ignited cloud
with local equipment layout can result in large overpressures and
consequent equipment damage.
6.2.4. Conducted heat
When hot work is carried out on one part of metal structure, heat will be
conducted to connected parts.
Depending on the shape and what else is in contact with the metal, the
temperature rise may be enough to ignite a fire remote from the hot work,
e.g. in a room from another side of a partition.
Conducted heat can also cause the pressure to rise inside any fully
enclosed space or equipment, especially if liquid traces are present and
become vaporized.
6.3. Controlling Hot Work
6.3.1 Minimum Requirements for Controlling Hot Work
- All personnel with assigned responsibilities for the control of hot work shall be
competent to carry out those responsibilities
- There shall be a documented local procedure for the control of hot work, as part
of the local Permit to work arrangements
- Hot work shall be subject to a Risk assessment at the planning stage and task-
specific controls implemented to ensure that :
o all combustible materials within 50 feet have been removed, isolated, and/or
protected from the source(s) of ignition
o where relevant, control measures are in place to keep oxygen levels and
flammable vapour within acceptable limits
o in hazardous areas, the atmosphere affected by the hot work is regularly
tested by a competent person as often as the Risk assessment requires
o Suitable fire fighting equipment is readily available and accessible at the hot
work site
o For primary source of ignition hot work, the area is monitored by one or more
competent firewatchers both during the hot work and subsequently to ensure
smoldering debris remains.
- All hot work tasks and their agreed controls) are approved by a competent
person in accordance with PTW Procedures
- A fire watcher must be present to monitor the work area while fire and gas
system are inhibited for naked flame hot work, e.g., welding and burning. The fire
watcher is responsible for ensuring that :
o He is in possession of a radio for immediate emergency communication, or
he is aware of the location of the nearest radio point for communicating with
the facility control point.
o Fire fighting equipment is available and ready for immediate use
o He is trained and able to demonstrate his competence in handling relevant
fire fighting equipment
o Flammable materials are cleared away from the work site
o Drains remain covered and sealed
o Sparks and welding spatter are contained (by the use of fire blankets, water
sprays etc.)
o The alarm is raised where a fire of gas release occurs in the area
o Upon completion of the task, all relevant fire fighting equipment is returned to
its appropriate storage location.
6.3.2 Hot Work Control Process
6.3.3 Hot Work Controls Hierarchy
1) ELIMINATION
Hot work must not take place until all other options have been ruled out.
2) SUBSTITUTIONS
The use of alternative techniques and equipment should be considered
when planning hot work activity, for example:
- A bolted bracket might be suitable alternative to a welded one, where
such solutions are technically and economically acceptable, they should
be used instead of hot work tasks
- Use of pneumatic equipment (e.g. drills) rather than electrically powered
equipment
- Where regular use of diesel power is required in a hazardous area, it is
possible to use specially designated engines, which have overspeed
protection, air inlet closure valve ex-rated electrical accessories.
Such engines may be available for forklift trucks, air compressors, and
electrical generators, and should be used for such service when
available.
However, it is unlikely that this means avoiding the hazard will be
possible in all cases. For example, mobile cranes , construction, and
delivery vehicles, fire appliances, etc, may need to operate within or
adjacent to hazardous areas from time to time.
Therefore site controls need to take account of standard diesel engine,
and petrol-engine vehicles.
3) ENGINEERING
Improving workplace design and layout :
- Removing all types of fuel from the area before work starts, or preventing
any possible contact between remaining fuel and ignition source(s)
- Ensuring that, while the hot work continues, additional fuel cannot be
unexpectedly spilled or released into the work area.
4) PERSONAL PROTECTIVE EQUIPMENT & EMERGENCY RESPONSE
Mitigation measures to reduce the affects of an accident or condition –
must be in place to minimize the impact of any residual risks.
These will include:
- Appropriate PPE, including fire resistant clothing. Note PPE shall
only considered as the last protective barrier before a person is
exposed the hazard. Reliance on PPE shall only occur after all
other efforts have been made to eliminate or reduce the hazard
- The welder must use appropriate PPE for welding
- Emergency response arrangements
6.4. Hot Work Implementation
6.2.5. General
To insure the safety of personnel, all hot work must be done under
controlled conditions.
This control established by proper development of a Hot Work permit for the
particular work at hand, and strict enforcement of its provisions.
The Area Authority responsible for the area will sign the hot work permit
certificate. The signer of a permit must be very knowledgeable about the
current status of operations, any unplanned or potential changes in the work
area and the nature of the hot work to be performed. Each permit must
reflect the particular nature of the job, the specific location where work is to
be performed and the specific conditions that exist at the time.
The Area Authority who is authorized to approve hot work must verify all
conditions of permit are correct and include a visit to the proposed hot work
site. If the authorized individual is satisfied the work may proceed safely,
they will then sign the permit.
6.2.6. Scope of Work
Care must be taken to avoid attempting to approve too much work under
one permit. Only the work specified on the permit is allowed. If more work is
necessary or a different type of work contemplated, then a new permit must
be written.
If condition change, discovered other by the work crew or the crew
responsible for the area the existing permit must be revoked and a new
permit written to reflect the new conditions.
- A specific description of the contemplated work is required
- Each separate job site must have its own work permit. Permits should be
written for specific areas not entire units
- Each set of conditions that exist in a given area will require separate permit
- Work that is not specifically described on the permit is not authorized and
cannot be done unless new permit is prepared and issued
6.2.7. Site preparation
Before the hot work starts, verification must be made to insure that the
instructions listed on the permit have been carefully followed. Both the crew
responsible for the area and the maintenance and/or contractor supervisor
in charge of the hot work must carry out the responsibility.
Only after both groups are satisfied the permit conditions have been met
should the approval to start the hot work be given.
- Area clean-up. Before the approval to begin the hot work can be given, the
area where the work will be performed must be properly cleaned up to
eliminate potential combustible material. A hot work area is generally
considered to be within a 50 inch minimum radius of the site of the hot work
- All spills of combustible liquids in the area of hot work must be properly
cleaned up and area fully gas tested prior to any permit being issued.
- All potential source of leaks, such as pump seals, valve packing, flanges
and drains in the area of the hot work, shall be checked to insure none are
leaking
- All storage containers of flammables must be moved to safe location
All other combustible material shall be cleaned up and moved to a safe
location
6.2.8. Site Visit
In order to be fully knowledgeable about current conditions at a hot work
site, the permit writer and other signers will need to visit the site before
completing the permit.
All signers need this current knowledge to avoid making assumptions about
site conditions and to avoid writing generalized permit that doesn’t address
the specifics of the particular job.
6.2.9. Gas Testing
With the introduction of an ignition source into the area covered by the hot
work permit, we must be absolutely sure there are no flammable vapors in
the area.
Gas testing must be done prior to the start of hot work to verify it is safe to
begin. Continuous gas testing might be required to provide warning of
vapors entering the area due to some change in conditions during the
performance the work.
Extreme care must be taken in specifying the nature of the testing required,
in performing the manual testing and in placing to continuous monitor to
service.
The gas testing must be performed by the Authorized Gas Tester
6.5. Requirements
6.2.10. Fire Equipment requirements
- Fire equipment is required at the location each hot work area to flight
incipient fires, which may develop in spite of all precautions taken.
- 4.5 kg dry chemical extinguishers, or equal, are required at a minimum at
each hot work site.
- Fire blanket for spark control : on certain hot work jobs, the generated
sparks may carry a distance, horizontally and vertically
The permit writer shall specify the method of spark control, if required, such
as water spray of fireproof blankets.
6.2.11. Periodic manual gas testing
- A manual gas test must be given prior to the start of hot work. Periodic re-
tests must be given at least once per mechanical shift.
The purpose of the manual test is to provide final assurance that the area is
safe for hot work proceed and that all permit conditions have been met.
The periodic re-tests are made to assure there have been no changes in
conditions
- Gas testing must be undertaken immediately prior to issue of any permit
and as soon as practical before hot work commences then a further gas test
is required
- Permit approver must specify frequency of periodic gas test to be conducted
during the hot work
6.2.12. Continuous Gas Monitor
A continuous gas monitor is used to provide early warning of the presence
of flammable vapors. Its use is required when performing hot work on
operating units and its use is recommended in other hot work settings.
7. ATTACHMENTS
7.1 Attachment-1
