5.1.2* The AHJ shall be consulted regarding the required type of system, class of system, and special requirements.

5.1.3 The spacing and location of standpipes and hose connections shall be in accordance with Chapter 7.

5.1.4 Standpipe and hose systems not required by the AHJ and not meeting the requirements of this standard shall be marked with a sign that reads “FOR FIRE BRIGADE USE ONLY.”

5.2 Automatic and Semiautomatic Dry Systems.

5.2.1* Automatic Dry.

5.2.1.1 Pressure Gauges. Listed pressure gauges conforming with Section 5.5 shall be connected as follows:
(1) On the water side and air side of the dry pipe valve
(2) At the air pump supplying the air receiver where one is provided
(3) At the air receiver where one is provided
(4) In each independent pipe from air supply to dry pipe system
(5) At exhausters and accelerators [13:7.2.1]

5.2.1.2 Size of Systems Volume Limitations.

5.2.1.2.1* Not more than 750 gal (2839 L) system capacity shall be controlled by one dry pipe valve. [13:7.2.3.1]

5.2.1.2.2 Piping volume shall be permitted to exceed the requirements of 5.2.1.2.1 where the system design is such that water is delivered to the system at the most remote hose connection in not more than 3 minutes, starting at the normal air pressure on the system and at the time of fully opened hose connection.

5.2.1.2.3 The use of a listed quick opening device shall be permitted in order to meet the requirements of 5.2.1.2.2.

5.2.1.3* Location and Protection of Dry Pipe Valve. [13:7.2.5]

5.2.1.3.1* General. The dry pipe valve and supply pipe shall be protected against freezing and mechanical injury. [13:7.2.5.1]

5.2.1.3.2 Valve Rooms. [13:7.2.5.2]

5.2.1.3.2.1 Valve rooms shall be lighted and heated. [13:7.2.5.2.1]

5.2.1.3.2.2 The source of heat shall be of a permanently installed type. [13:7.2.5.2.2]

5.2.1.3.2.3 Heat tape shall not be used in lieu of heated valve enclosures to protect the dry pipe valve and supply pipe against freezing. [13:7.2.5.2.3]

5.2.1.3.3 Low Differential Dry Pipe Valve. Protection against accumulation of water above the clapper shall be provided for a low differential dry pipe valve. [13:7.2.5.4.2]

5.2.1.3.4 High Water Level Device. An automatic high water level signaling device or an automatic drain device shall be permitted. [13:7.2.5.4.3]

5.2.1.4 Air Pressure and Supply. [13:7.2.6]

5.2.1.4.1 Maintenance of Air Pressure. Air or nitrogen pressure shall be maintained on dry pipe systems throughout the year. [13:7.2.6.1]

5.2.1.4.2* Air Supply. [13:7.2.6.2]

5.2.1.4.2.1 The compressed air supply shall be from a source available at all times. [13:7.2.6.2.1]

5.2.1.4.2.2 The air supply shall have a capacity capable of restoring normal air pressure in the system within 30 minutes. [13:7.2.6.2.2]

5.2.1.4.3 Air Supply Connection. [13:7.2.6.3]

5.2.1.4.3.1 Connection pipe from the air supply shall not be less than 1⁄2 in. (15 mm) in diameter and shall enter the system above the priming water level of the dry pipe valve. [13:7.2.6.3.1]

5.2.1.4.3.2 A check valve shall be installed in this air line, and a shutoff valve of the renewable disc type shall be installed on the supply side of this check valve and shall remain closed unless filling the system. [13:7.2.6.3.2]

5.2.1.4.4 Relief Valve. An approved relief valve shall be provided between the air supply and the shutoff valve and shall be set to relieve pressure no less than 10 psi (0.7 bar) in excess of system air pressure provided in 5.2.1.4.10 and shall not exceed the manufacturer’s limitations. [13:7.2.6.4]

5.2.1.4.5 Automatic Air Maintenance. Unless the requirements of 5.2.1.4.6 are met, where the air supply to a dry pipe system is maintained automatically, the air supply shall be from a dependable plant system or an air compressor with an air receiver, and shall utilize an air maintenance device specifically listed for such service and capable of controlling the required air pressure on, and maximum airflow to, the dry system [13:7.2.6.5.1]

5.2.1.4.6 Where the air compressor supplying the dry pipe system has a capacity less than 5.5 ft3/min (156 L/min) at 10 psig (0.7 bar), no air receiver or air maintenance device shall be required. [13:7.2.6.5.2]

5.2.1.4.7 The automatic air supply to more than one dry pipe system shall be connected to enable individual maintenance of air pressure in each system. [13:7.2.6.5.3]

5.2.1.4.8 A check valve or other positive backflow prevention device shall be installed in the air supply to each system to prevent airflow or waterflow from one system to another. [13:7.2.6.5.4]

5.2.1.4.9 System Air Pressure. [13:7.2.6.6]

5.2.1.4.10 The system air pressure shall be maintained in accordance with the instruction sheet furnished with the dry pipe valve, or shall be 20 psi (1.4 bar) in excess of the calculated trip pressure of the dry pipe valve, based on the highest normal water pressure of the system supply. [13:7.2.6.6.1]

5.2.1.4.11 The permitted rate of air leakage shall be as specified in 5.2.1.4.12. [13:7.2.6.6.2]

5.2.1.4.12 In addition to the standard hydrostatic test, an air pressure leakage test at 40 psi (2.8 bar) shall be conducted for 24 hours. Any leakage that results in a loss of pressure in excess of 11⁄2 psi (0.1 bar) for the 24 hours shall be corrected. [13:24.2.2.1]

5.2.1.4.13 Nitrogen. Where used, nitrogen shall be introduced through a pressure regulator set to maintain system pressure in accordance with 5.2.1.4.5. [13:7.2.6.7]

5.2.2 Auxiliary Systems. A wet standpipe system shall be permitted to suppy an auxiliary dry standpipe system, provided the water supply is capable of supplying the system demand. [13:7.1.3]

5.2.3 Semiautomatic Dry.

5.2.3.1 A listed remote control activation device shall be provided at each hose connection within 3 ft (1 m) and shall be visible and identified as to its intended use and in accordance with the manufacturer’s specifications.

5.2.3.1.1 The remote control activation device shall be permitted to be secured in an approved manner to prevent unauthorized system activation.

5.2.3.1.2 The remote control activation system shall be installed in accordance with NFPA 72, National Fire Alarm and Signaling Code.

5.2.3.1.3* The remote control activation circuits shall be protected from mechanical damage.

5.2.3.1.4 All wiring for actuation of semiautomatic systems shall be supervised in accordance with NFPA 72, National Fire Alarm and Signaling Code.

5.2.3.2 All remote control activation devices of the semiautomatic dry standpipe system shall be compatible and listed for the intended use.

5.2.3.3* The automatic water control valve shall be provided with hydraulic means or mechanical manual means for operation that is independent of the remote control activation device.

5.2.3.4 Pressure Gauges. Listed pressure gauges conforming with Section 5.5 shall be installed as follows:
(1) Above and below preaction valve and below deluge valve
(2) On air supply to preaction and deluge valves [13:7.3.1.3]

5.2.3.5 Location and Protection of System Water Control Valves. [13:7.3.1.8]

5.2.3.5.1 System water control valves and supply pipes shall be protected against freezing and mechanical injury. [13:7.3.1.8.1]

5.2.3.5.2 Valve Rooms. [13:7.3.1.8.2]

5.2.3.5.2.1 Valve rooms shall be lighted and heated. [13:7.3.1.8.2.1]

5.2.3.5.2.2 The source of heat shall be of a permanently installed type. [13:7.3.1.8.2.2]

5.2.3.5.2.3 Heat tape shall not be used in lieu of heated valve enclosure rooms to protect preaction and deluge valves and supply pipe against freezing. [13:7.3.1.8.2.3]

5.2.3.6 Semiautomatic dry systems shall be one of the following types:
(1) A single interlock system, which admits water to piping upon operation of the remote control activation device
(2) A non-interlock system, which admits water to piping upon operation of remote control activation device or hose valve
(3) A double interlock system, which admits water to piping upon operation of both remote control activation devices and hose valves

5.3 Classes of Standpipe Systems.

5.3.1 Class I Systems. A Class I standpipe system shall provide 21⁄2 in. (65 mm) hose connections to supply water for use by fire departments and those trained in handling heavy fire streams.

5.3.2 Class II Systems.

5.3.2.1 A Class II standpipe system shall provide either 11⁄2 in. (40 mm) hose stations to supply water for use by trained personnel or a hose connection for the fire department during initial response.

5.3.2.2 A minimum 1 in. (25.4 mm) hose shall be permitted to be used for hose stations in light hazard occupancies where investigated and listed for this service and where approved by the authority having jurisdiction.

5.3.3 Class III Systems. A Class III standpipe system shall provide 11⁄2 in. (40 mm) hose stations to supply water for use by trained personnel and 21⁄2 in. (65 mm) hose connections to supply a larger volume of water for use by fire departments and those trained in handling heavy fire streams.

5.3.3.1 A minimum 1 in. (25.4 mm) hose shall be permitted to be used for hose stations in light hazard occupancies where investigated and listed for this service and where approved by the authority having jurisdiction.

5.3.3.2 Where the building is protected throughout by an approved automatic sprinkler system, Class II hose stations for use by trained personnel shall not be required, subject to the approval of the AHJ, provided that each Class I hose connection is 21⁄2 in. (65 mm) and is equipped with a 21⁄2 in.× 11⁄2 in. (65 mm × 40 mm) reducer and a cap attached with a chain, and the 130 ft (39.7 m) travel distance limitation shall not apply.

5.4* Required Type of System.

5.4.1 Class I Standpipe Systems.

5.4.1.1* Class I standpipe systems shall be permitted to be automatic dry, automatic wet, semiautomatic dry, manual dry, or manual wet in buildings not classified as high-rise buildings.

5.4.1.2 Class I standpipe systems in buildings classified as high-rise buildings shall be automatic or semiautomatic.

5.4.1.2.1 In buildings classified as high-rise, all required standpipes shall be automatic or semiautomatic, including partial height and horizontal standpipes that serve only a portion or limited number of floors within the building.

5.4.1.3 Where an existing standpipe system having standpipes with a minimum diameter of 4 in. (100 mm) is to be utilized to supply a new retrofit sprinkler system, the water supply required by Section 7.10 shall not be required to be provided by automatic or semiautomatic means, provided that the water supply is adequate to supply the hydraulic demand of the sprinkler system in accordance with NFPA 13, Standard for the Installation of Sprinkler Systems.

5.4.1.4 Class I standpipe systems shall be wet systems except where piping is subject to freezing.

5.4.2 Class II and Class III Standpipe Systems. Class II and Class III standpipe systems shall be automatic wet systems unless located in a facility where piping is subject to freezing and where a fire brigade is trained to operate the system without fire department intervention, in which case an automatic dry or semiautomatic dry system shall be permitted.

5.4.2.1* The automatic portion of a Class III system shall be permitted to be only what is required for a Class II system unless the Class I portion requires an automatic water supply.

5.5* Gauges.

5.5.1 Alisted 31⁄2 in. (90 mm) dial spring pressure gauge shall be connected to each discharge pipe from the fire pump and the public waterworks, at the pressure tank, at each main drain connection, at the air pump supplying the pressure tank, and at the top of each standpipe.

5.5.1.1 Gauges shall be located in a place so that water cannot freeze.

5.5.1.2 Each gauge connection shall be equipped with a shutoff valve and provisions for draining.

5.5.1.3 Where several standpipes are interconnected at the top, a single gauge shall be permitted to be substituted for a gauge at the top of each standpipe.

5.5.1.4 Pressure gauges shall be installed above and below each alarm check valve, dry pipe valve, deluge valve, backflow preventer, or system riser check valve where such devices are present.

5.5.2* Pressure-Regulating Device.

5.5.2.1 A valved outlet for a pressure gauge shall be installed on the upstream side of every pressure-regulating device.

5.5.2.2 Pressure gauges shall be installed on the upstream and the downstream sides of every pressure-regulating device installed in accordance with 7.2.4(6).

5.6* Waterflow and Supervisory Alarms.

5.6.1 Except for manual dry systems, listed waterflow and control valve supervision shall be provided for each standpipe system.

5.6.2 Waterflow alarms shall utilize a sensing mechanism appropriate to the type of standpipe.

5.6.3 Paddle-type waterflow alarms shall be used on wet standpipe systems only.

5.6.4 A test connection for testing the waterflow device shall be provided.

5.6.5 Alarm and supervisory devices shall be installed in accordance with NFPA 72, National Fire Alarm and Signaling Code.