SYSTEM TYPES AND REQUIREMENTS 13-59

8-3-2-3-2 A listed quick-opening device shall be permitted to 8A.2.2 Combined automatic dry pipe and preaction systems
be used to help meet the requirements of 8.3.2.3.1.2, shall be so constructed that failure of the dry pipe system of
8.3.2.3.1.3, and 8.3.2.3.1.4. automatic sprinklers shall not prevent the detection system
8-3-2A* Supervision- Sprinkler piping and fire detection
from properly functioning as an automatic fire alarm system.
devices shall be automatically supervised where more than 20 8A.2.3 Provisions shall be made for the manual operation of

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sprinklers are on the system. the detection system at locations requiring not more than
8-3-2-5 Air Pressure Except as provided by 8.3.2.5.1through
200 ft (61 m) of travel.
8.3.2.5.3, air or nitrogen supervising pressure for preaction SA.2A Sprinklers. The following types of sprinklers and
systems shall be installed in conformance with the dry pipe arrangements shall be permitted for combined dry pipe and
system air pressure and supply rules of 8.2.6. preaction systems:
8.3.2.5.1 The relief valves required by 8.2.6 shall be permitted (1) Upright sprinklers
to be omitted for the type of preaction system described in (2) * Listed dry sprinklers
8.3.2.1(1) when the air pressure is supplied from a source that (3) Pendent sprinklers and sidewall sprinklers installed on
is not capable of developing pressures in excess of 15 psi (1.0 return bends, where both the sprinklers and the return
bar). bends are located in a heated area
8.3.2.5.2 A preaction system type described in 8.3.2.1 (2) and
( 4) Horizontal sidewall sprinklers, installed so that water is
8.3.2.1 (3) shall maintain a minimum supervising air or nitro­ not trapped
gen pressure of 7 psi (0.5 bar). 8A.3 Dry Pipe Valves in Combined Systems.

N 8.3.2.5.3 The air pressure values for the type of preaction 8A.3.1 Where the system consists of more than 600 sprinklers
system described in 8.3.2.1(l)shall be set in accordance with or has more than 275 sprinklers in any fire area, the entire
the manufacturer's installation instructions. system shall be controlled through two 6 in. (150 mm) dry pipe
8.3.2.6 Sprinklers. The following sprinkler orientations and
valves connected in parallel and shall feed into a common feed
arrangements shall be permitted for preaction systems: main.
8A.3.2* Where parallel dry pipe valves are required by 8.4.3.1,
(1) Upright sprinklers these valves shall be checked against each other.
(2) * Listed dry sprinklers
(3) Pendent sprinklers and sidewall sprinklers installed on 8A.3.3 Each dry pipe valve shall be provided with a listed trip­
return bends, where the sprinklers, return bend, and ping device actuated by the detection system.
branch line piping are in an area maintained at or above SA.3A Dry pipe valves shall be cross-connected through a
40°F WC) 1 in. (25 mm) pipe connection to permit simultaneous tripping
(4) Horizontal sidewall sprinklers, installed so that water is of both dry pipe valves.
not trapped
(5) Pendent sprinklers and sidewall sprinklers, where the 8A.3.5 The 1 in. (25 mm) cross-connection pipe shall be
sprinklers and branch line piping are in an area main­ equipped with an indicating valve so that either dry pipe valve
tained at or above 40°F (4o q , the water supply is potable, can be shut off and worked on while the other remains in serv­
and the piping for the preaction system is copper or ice.
CPVC specifically listed for dry pipe applications 8A.3.6 The check valves between the dry pipe valves and the
8.3.2.7 System Configuration. Preaction systems of the type
described in 8.3.2.1 (3) and all preaction systems protecting common feed main shall be equipped with )'2 in. (15 mm)
storage occupancies, excluding miscellaneous storage, shall not bypasses so that a loss of air from leakage in the trimmings of a
be gridded. dry pipe valve will not cause the valve to trip until the pressure
in the feed main is reduced to the tripping point.
8.3.3* Deluge Systems. 8A.3.7 An indicating valve shall be installed in each of these
8.3.3.1 The detection devices or systems shall be automatically bypasses so that either dry pipe valve can be completely isolated
supervised. from the main riser or feed main and from the other dry pipe
valve.
8.3.3.2 Deluge systems shall be hydraulically calculated.
8A.3.8 Each combined dry pipe and preaction system shall be
SA Combined Dry Pipe and Preaction Systems for Piers, provided with listed quick-opening devices at the dry pipe
Terminals, and Wharves. valves.
8A. 1 In addition to the requirements of Section 8.4, design BAA Subdivision of System Using Check Valves.
and installation requirements for piers, terminals, and wharves SAA.1 Where more than 275 sprinklers are required in a
shall be in accordance with Section 27.27. single fire area, the system shall be divided into sections of 275
SA.2* General. sprinklers or fewer by means of check valves.
8A.2.1 * Combined automatic dry pipe and preaction systems SAA.2 Where the system is installed in more than one fire
shall be so constructed that failure of the detection system shall area or story, not more than 600 sprinklers shall be supplied
not prevent the system from functioning as a conventional through any one check valve.
automatic dry pipe system.

Shaded text = Revisions. .0. = Text deletions and figure/table revisions. • = Section deletions. N = New material. 2022 Edition