N.Y.C. Admin. Code § FC 904: Section FC 904: Fire Extinguishing Systems

904.1 General.

Fire extinguishing systems shall be designed, installed, operated and maintained in accordance with this section, FC 901, the terms and conditions of the listing, if applicable, the applicable referenced standards set forth in FC Table 904.1, and the manufacturer's instructions.

Exception: Sprinkler systems, which are governed by FC 903.

FC Table 904.1 Fire Extinguishing System Referenced Standards

Fire Extinguishing System

Referenced Standard

Aerosol fire extinguishing systems

NFPA 2010

Carbon dioxide fire extinguishing system

NFPA 12

Clean agent fire extinguishing systems

NFPA 2001

Dry chemical fire extinguishing systems

NFPA 17

Expansion foam systems (low, medium and high)

NFPA 11

Foam water sprinkler and spray systems

NFPA 16 and NFPA 25

Halon 1301 fire extinguishing systems

NFPA 12A

Water mist fire extinguishing systems

NFPA 750

Water Spray Fixed Systems for Fire Protection

NFPA 15

Wet chemical fire extinguishing systems

NFPA 17A

904.1.1 Fire extinguisher system design.

Fire extinguishing systems may be engineered or pre-engineered. Pre-engineered systems shall be of a type for which a certificate of approval has been issued in accordance with FC 112 and 901.4.5. Except as otherwise provided in this code or other applicable law, rule, regulation or standard, fire extinguishing systems may be designed as local applications or as total flooding systems. All activation devices and other system components shall be listed and installed in accordance with the listing and the manufacturer's instructions.

904.1.2 Installation acceptance testing.

All fire extinguishing systems shall be subject to acceptance test conducted at the owner's risk by his or her representative before a representative of the department. The owner's representative shall furnish the necessary equipment required to conduct the test. A discharge test may be required as set forth in the applicable installation standard or as required by the department when there is evidence that the system will not provide the necessary level of protection.

904.1.3 Additional safeguards.

If an area is protected by a fire extinguishing system which uses an extinguishing agent that will make the protected area hazardous by its discharge or thermal decomposition, suitable safeguards shall be provided to ensure prompt evacuation, to prevent entry into such atmospheres, and to provide means for prompt rescue of any trapped personnel. Such safeguards shall include establishment of a trained brigade, equipped with and qualified in the use of self-contained breathing apparatus with 30-minute minimum supply, for prompt search of the protected area.

Exception: Self-contained breathing apparatus shall not be required for a clean agent fire extinguishing system installation if:

1. The installation is provided with an alarm system that is connected to an approved central station.

2. The protected area is provided with an approved fixed emergency forced ventilation system able to expel the extinguishing agent. Such emergency forced ventilation system shall have a capacity sufficient to effect at least twenty air changes per hour.

3. The protected area is of a size, design and/or occupied in such a manner that egress will not be impeded.

4. The protected area is not normally occupied by any individual requiring assistance in evacuation.

904.1.4 Prohibited fire extinguishing systems.

It shall be unlawful to install carbon dioxide, halon and clean agent fire extinguishing systems as set forth in FC 904.1.4.1 through 904.1.4.3.

904.1.4.1 Existing carbon dioxide systems.

It shall be unlawful to install or continue to maintain total flooding carbon dioxide fire extinguishing systems within normally occupied areas, including commercial kitchens. Total flooding carbon dioxide systems installed in normally occupied areas prior to July 1, 2008 were required by this code to be removed by July 1, 2013. Existing total flooding carbon dioxide fire extinguishing systems in such areas shall be removed and a replacement fire extinguishing system installed, where required, in accordance with the Building Code, this code or other applicable laws, rules and regulations.

904.1.4.2 Existing halon systems.

It shall be unlawful to install a halon system in any building or occupancy. Lawfully existing halon fire extinguishing systems shall be maintained in accordance with FC 904.5. If a lawfully existing system cannot be maintained under the laws, rules, regulations, standards and design and installation approvals under which it was installed, such system shall be removed and replaced with a type of fire extinguishing system complying with this code.

904.1.4.3 Clean agent systems.

It shall be unlawful to install clean agent systems that are not total flooding systems. Lawfully existing clean agent fire extinguishing systems that are not total flooding systems shall be maintained in accordance with FC 904.5. If a lawfully existing system cannot be maintained under the laws, rules, regulations, standards and design and installation approvals under which it was installed, such system shall be removed and replaced with a type of fire extinguishing system complying with this code.

904.2 Where required.

Where this code or the rules requires the installation of a fire extinguishing system, other than a sprinkler system, the commissioner shall approve the type of fire extinguishing system to be installed. Fire extinguishing systems installed as an alternative to sprinkler systems otherwise required by this code or the construction codes, including the Building Code, shall be approved by the commissioner. Such a system may be accepted by the commissioner where the nature of the fire hazard is such that water would be ineffective or hazardous as an extinguishing agent, or the need to preserve the historic, irreplaceable or special nature of the contents of the occupancy militates against the installation of a sprinkler system. Sprinklers shall not be omitted from any room or area merely because it is of fire-resistance-rated construction or contains electrical equipment except as allowed by Section 903 of the Building Code.

If a system using a fixed amount of extinguishing agent is authorized to be installed in lieu of a required sprinkler system or any other fire extinguishing system otherwise required by law, a connected reserve of charged agent cylinders equal to the primary supply shall be provided. The commissioner may impose additional requirements on the installation of any fire extinguishing system to be installed in lieu of any required sprinkler system. Fire extinguishing systems shall not be considered alternatives for the purposes of exceptions or reductions allowed by other requirements of this code.

904.3 Installation.

Fire extinguishing systems shall be installed in accordance with this section.

904.3.1 Electrical wiring.

Electrical wiring shall be in accordance with the Electrical Code.

904.3.2 Activation.

Unless otherwise provided by this code or the rules, fire extinguishing systems shall be designed and installed to activate automatically. Automatically activating fire extinguishing systems shall additionally be provided with a manual means of activation.

904.3.3 System interlocking.

Automatic equipment interlocks with fuel shutoffs, ventilation controls, door closers, window shutters, conveyor openings, smoke and heat vents, and other features necessary for proper operation of the fire extinguishing system shall be provided as required by the construction code or other design and installation standard utilized for the hazard.

904.3.4 Alarms and warning signs.

Where alarms are required to indicate the operation of fire extinguishing systems, distinctive audible, visible alarms and warning signs shall be provided to warn of pending agent discharge. Where exposure to automatic-extinguishing agents poses a hazard to persons and a delay is required to ensure the evacuation of occupants before agent discharge, a separate warning signal shall be provided to alert occupants once agent discharge has begun. Carbon dioxide fire extinguishing systems, where allowed, shall comply with the signage requirements of NFPA 12.

904.3.5 Monitoring.

All indoor fire extinguishing systems, except commercial cooking, domestic cooking and spray finishing fire extinguishing systems, installed after the effective date of this section shall be monitored by an approved central station. Where a building fire alarm system is installed, all such indoor fire extinguishing systems, except domestic cooking systems, shall be monitored by such fire alarm system.

904.3.6 Flood hazard.

Non-water fire extinguishing system control panels located in areas of special flood hazard or on the premises of Group I-2 occupancies that are hospitals located in shaded X-Zones (as defined in Section G201.2 of Appendix G of the Building Code) shall be located at or above the design flood elevation in accordance with Appendix G of the Building Code.

904.3.7 Additional safety measures.

Additional safety measures shall be provided for the fire extinguishing systems as set forth in FC 904.3.7.1 and 904.3.7.2.

904.3.7.1 Carbon dioxide systems.

Carbon dioxide systems, where allowed, shall be provided with the additional safety measures set forth in FC 904.3.7.1.1 through 904.3.7.1.8.

904.3.7.1.1 Egress precautions.

All areas whose atmospheres will be made hazardous by the discharge of carbon dioxide shall be provided with:

1. Exit and exit routes that are kept clear at all times.

2. Lighting and exit directional signs in accordance with the construction codes, including the Building Code.

3. Only outward swinging, self-closing doors at exits, and panic hardware on any such doors that are secured with a locking or latching device.

904.3.7.1.2. Ventilation and other safety equipment.

A carbon dioxide system shall be provided with a fixed emergency forced ventilation system able to clear the area with sufficient capacity to accomplish at least 6 air changes per hour, and such other safety equipment as may be prescribed by the commissioner.

904.3.7.1.3 Detection, activation, alarm and control.

Detection, predischarge alarms and discharge alarms shall be provided within and outside the protected area and such other areas that are made hazardous by a carbon dioxide discharge. Such alarms shall be audible and visible.

904.3.7.1.3.1 Automatic operation.

The carbon dioxide fire extinguishing system shall be activated by an automatic cross-zoned detection system in which activation of a detection device in one zone shall sound a local alarm and transmit an alarm to an approved central station, and activation of a detection device in the cross zone shall initiate the predischarge warning signal and after a time delay, initiate the discharge of carbon dioxide. The predischarge warning signal time delay shall be of sufficient duration to allow for evacuation from the protected area. Distinct alarms shall indicate the activation of a detector in one zone, the activation of a detector in a cross zone (predischarge alarm) and the discharge of carbon dioxide. Such alarms shall be continued until the atmosphere has been returned to normal except that the alarm for the detector in one zone may be discontinued when the alarm for the cross-zoned detector is activated.

Exceptions:

1. A carbon dioxide fire extinguishing system activated solely by manual means may be installed with department approval upon a showing satisfactory to the department of the need for such a system.

2. A detection system that is not cross-zoned may be installed with department approval upon a showing satisfactory to the department of the need for such a detection and activation system.

904.3.7.1.3.2 Manual operation.

A manual pull station shall be provided which, upon activation, transmits an alarm to an approved central station, overrides any delay other than the predischarge delay, and causes the carbon dioxide to discharge. Activation of a carbon dioxide fire extinguishing system by means of a manual pull station shall result in a complete predischarge delay sequence prior to system discharge.

904.3.7.1.3.3 Abort systems.

Abort systems may be installed, but shall be limited to systems activated by smoke detectors. Abort controls shall be located in the protected area near the means of egress for the area, and shall be designed to cause the discharge of carbon dioxide after a time delay unless the abort control is reactivated for another cycle of delay. Abort controls shall not interfere with transmission of local alarms or central station alarms.

904.3.7.1.3.4 Power supply.

Power supply to the alarm system shall be in accordance with applicable requirements of the Electrical Code and the construction codes, including the Building Code.

904.3.7.1.4 Pressure relief venting.

The protected area enclosure shall be provided with suitable pressure relief venting which vents outdoors.

Exception: Such venting shall not be required when a registered design professional certifies that the walls, ceilings and floors comprising the protected space have sufficient porosity and leakage to prevent damage to the integrity of such space upon discharge of the extinguishing agent, and that the inert gas agent leakage into other non-flooded rooms and spaces will not reach dangerous concentrations.

904.3.7.2 Clean agent systems.

Clean agent systems, where allowed, shall be provided with the additional safety measures set forth in FC 904.3.7.2.1 through 904.3.7.2.6.

904.3.7.2.1 System alarm and activation.

Audible and visible alarms shall be installed both inside and outside the protected area to signal the activation of an automatic detection device and the operation of the fire extinguishing system. Such signals shall continue until the atmosphere has been returned to normal. Activation of a single automatic detection device shall sound a local alarm and transmit an alarm to an approved central station. Unless the alarm is cancelled by an abort system as set forth in FC 904.3.7.2.3, activation of a second automatic detection device shall, within 30 seconds, initiate the discharge of clean agent. Power supply to the alarm system shall be in accordance with the Electrical Code, the construction codes, including the Building Code, and NFPA 2001, as modified by FC Appendix B.

904.3.7.2.2 Warning and instruction signs.

Warning and instruction signs shall be posted at entrances to and within the protected area subject to flooding.

904.3.7.2.3 Abort systems.

Abort systems may be installed only on systems activated by smoke detectors. Abort controls shall be manually operated, shall be located in the protected area, and shall cause the discharge of the clean agent after a 2-minute delay unless the abort control is reactivated for another cycle of delay. A manual pull station shall be provided which, upon activation, shall transmit an alarm to an approved central station, override the delay and cause the clean agent to discharge immediately. Abort controls shall not interfere with transmission of local alarms or central station alarms.

904.3.7.2.4 Means of egress.

Where the protected area is normally occupied, provision shall be made for adequate clear routes of exit with doors opening in direction of travel. Emergency lighting shall be provided for such exits. Exit directional signs shall clearly indicate the path of egress and exits shall be clearly marked.

904.3.7.2.5 Fixed emergency forced ventilation.

When the protected area is normally occupied, a fixed emergency forced ventilation system sufficient to accomplish at least six air changes per hour of the flooded protected area shall be provided unless all of the following apply:

1. The clean agent fire extinguishing system is used to extinguish a Class A fire.

2. The design concentration does not exceed the "no observable adverse effect level" for halocarbon agents, or "no effect level" for inert gas agents as defined in NFPA 2001, as modified by FC Appendix B.

3. If other than inert gas agents are used, the quantity of the thermal decomposition products formed from such agents is below the dangerous toxic load (DTL) for humans as described in Meldrum's "Toxicology of Substances in Relation to Major Hazards: Hydrogen Fluoride" (HMSO, London, 1993). Upon request, documentation of hazard assessment of thermal decomposition products formed from such agents shall be filed with the department.

904.3.7.2.6 Pressure relief venting.

Clean agent fire extinguishing systems using inert gas agents shall be provided with suitable pressure relief venting for the flooded protected area that discharges outdoors.

Exception: Such venting shall not be required when a registered design professional certifies that the walls, ceilings and floors comprising the protected space have sufficient porosity and leakage to prevent damage to the integrity of such space upon discharge of the extinguishing agent, and that the inert gas agent leakage into other non-flooded rooms and spaces will not reach dangerous concentrations.

904.3.8 Commercial cooking systems.

Commercial cooking fire extinguishing systems shall be installed in accordance with FC 904.3.8.1 through 904.3.8.3.

904.3.8.1 Types of systems approved for commercial cooking operations.

Commercial cooking operations shall be protected by one of the following types of fire protection systems, as listed for commercial cooking operations.

1. Wet chemical fire extinguishing systems designed in accordance with NFPA 17A, as modified by FC Appendix B, and tested in accordance with UL 300.

2. Foam-water sprinkler system or foam-water spray systems designed in accordance with NFPA 16, as modified by FC Appendix B.

3. Water mist systems designed in accordance with NFPA 750, as modified by FC Appendix B.

904.3.8.1.1 Dry chemical, non-listed wet chemical and carbon dioxide systems.

Dry chemical systems, wet chemical systems not listed to the UL 300 standard and carbon dioxide systems may not be used for commercial cooking operations and shall be removed and replaced with a type of fire extinguishing system complying with this code.

904.3.8.2 Manual activation device.

A manual activation device for the fire extinguishing system, except foam-water systems, shall be installed at a location near a means of egress that is readily accessible from the cooking area and not less than 10 feet (3048 mm) nor more than 20 feet (6096 mm) from the commercial cooking appliances protected by the fire extinguishing system, or other approved location. The manual activation device shall be located a minimum of 42 inches (1067 mm) and a maximum of 48 inches (1219 mm) above the floor. The manual activation device shall require a maximum force of 40 pounds (178 N) and a maximum movement of 14 inches (356 mm) to activate the fire extinguishing system. A sign or marking in accordance with FC Table 609.7 that clearly identifies the commercial cooking appliances being protected shall be posted on or adjacent to the manual activation device. The manual activation device shall be kept unobstructed at all times.

904.3.8.3 System interconnection.

The activation of the fire extinguishing system shall automatically shut down the fuel and electrical power supply to the cooking equipment. The fuel and electrical supply reset shall be manual.

904.4 Installation inspection and testing.

Fire extinguishing systems shall be inspected and tested upon completion of the installation prior to the installation acceptance testing required by FC 904.1.2.

904.4.1 Inspection.

The fire extinguishing system shall be inspected for the following conditions:

1. Hazard specification for consistency with design hazard.

2. Type, location and spacing of automatic- and manual-initiating devices.

3. Size, placement and position of nozzles or discharge orifices.

4. Location and identification of audible and visible alarm devices.

5. Identification of devices with proper designations.

6. Operating instructions, to ensure that the system is correctly operated during the acceptance testing.

904.4.2 Alarm testing.

Notification appliances, connections to fire alarm systems, and connections to an approved central station shall be tested to verify proper operation, including the following conditions:

1. The audibility and visibility of notification appliances signaling agent discharge or system operation, where required, shall be verified.

2. Central station connections shall be tested to verify proper identification and retransmission of alarms.

904.5 Maintenance of fire extinguishing systems.

Fire extinguishing systems shall be periodically inspected, tested and otherwise maintained in accordance with FC 901, 904.1.1 and 904.4, the applicable NFPA standard, and the system listing. Additional maintenance shall be performed as set forth in FC 904.5.1 through 904.5.13*, FC Table 904.5.2, and the rules.

904.5.1 Monthly inspection.

At least once a month, a visual inspection of the fire extinguishing system shall be conducted by a trained and knowledgeable person to confirm that the system appears to be in good working order, including the following conditions:

1. The fire extinguishing system is intact and undamaged, including the extinguishing agent container, system piping, nozzles and protective nozzle caps.

2. Any fusible links or other fire detection devices are clean.

3. Access to each manual activation device, if required, for the fire extinguishing system is not obstructed and any tamper indicator is intact.

4. Check the pressure gauge, control panel or control unit, as applicable, to determine whether the fire extinguishing system is operational and whether there are any supervisory or trouble signals.

5. If an automatic foam system or water mist system, check the water supply valve to confirm that it is in the locked, open position; if the system is manually operated, confirm that the water supply is in good working order.

6. The maintenance tag for the fire extinguishing system is in place and has not expired.

904.5.2. Semiannual inspection.

A licensed master fire suppression piping contractor holding a certificate of fitness properly trained and having knowledge of the installation, operation and maintenance of the specific fire extinguishing system, or a person holding a certificate of fitness under the direction and control of such license holder, shall inspect, test, service and otherwise maintain such system in accordance with this section and the manufacturer's specifications and servicing manuals at least on a semiannual basis. Such semiannual inspection, testing and servicing shall include all procedures necessary to determine that the system is in good working order, including the following actions:

1. Verification that the hazard has not changed.

2. Verification that the fire extinguishing system has not been altered.

3. Examination of all detection systems, alarms, manual stations, extinguishing agent containers, releasing devices, piping, hose assemblies, nozzles, and all ancillary equipment.

4. Verification that the extinguishing agent has not been discharged.

5. Verification that the agent distribution piping is not obstructed.

6. Verification that the extinguishing agent container and/or ancillary pressure containers have been, as applicable, inspected, retested and marked in conformance with the requirements of the United States Department of Transportation.

7. A test of the system's automatic and manual releasing devices, including any associated equipment. Fixed temperature-sensing elements shall be maintained to ensure proper operation of the system.

8. A test of the gas and electric power source shut-off (interlock) devices, if applicable.

9. Preparation and submission to the owner of a written report of any system defects.

10. Upon satisfactory completion of the semiannual inspection and correction of all defects, providing the owner with an inspection, testing and service compliance tag. Such tag shall indicate the date issued, the name and license number of the licensed master fire suppression piping contractor issuing the tag and the certificate of fitness holder conducting the inspection, and that the system was found to be in compliance with the requirements of this section.

FC Table 904.5.2 Fire Extinguishing System Inspection, Testing and Maintenance Schedule

System

Inspection

Testing

Other Maintenance

Aerosol fire extinguishing systems

Monthly

Annually

Carbon dioxide fire extinguishing system

Monthly

Semiannually

Annually

Clean agent fire extinguishing systems

Monthly

Semiannually

Annually

Dry chemical fire extinguishing systems

Monthly

Semiannually

Expansion foam systems (low, medium and high)

Monthly

Annually

Foam water sprinkler and spray systems

See NFPA 25

Halon 1301 fire extinguishing systems

Monthly

Semiannually

Water mist fire extinguishing systems

See NFPA 25

Wet chemical fire extinguishing systems

Monthly

Semiannually

904.5.3 Five-year retest.

All fire extinguishing systems shall be retested once every five years from the date of acceptance of the system. The first retest of fire extinguishing systems lawfully existing on the effective date of this provision shall be conducted on or before the fifth anniversary of the date of acceptance after such effective date. Such test shall be conducted, and reported to the department, in the manner prescribed by rule, by a licensed master fire suppression contractor holding a certificate of fitness, properly trained and having knowledge of the installation, operation and maintenance of the specific fire extinguishing system, or a person holding a certificate of fitness under the direction and control of such license holder.

Exception: Commercial cooking and domestic cooking fire extinguishing systems.

904.6 Additional maintenance requirements.

The following fire extinguishing systems shall be maintained in accordance with the additional maintenance requirements set forth in FC 904.6.1 through 904.6.10.

904.6.1 Aerosol systems.

Aerosol fire extinguishing systems shall be maintained in accordance with FC 901.6.1 and 904.5.

904.6.2 Carbon dioxide systems.

Carbon dioxide systems shall be maintained in accordance with FC 901.6.1, 904.5 and 904.6.2.1 through 904.6.2.4.

904.6.2.1 High-pressure containers.

High-pressure containers shall be weighed and the date of the last hydrostatic test shall be verified at 6-month intervals. Where a container shows a loss in original content of more than 10 percent, the container shall be refilled or replaced.

904.6.2.2 Low-pressure containers.

The liquid-level gauges of low-pressure containers shall be observed at one-week intervals. Where a container shows a content loss of more than 10 percent, the container shall be refilled to maintain the minimum gas requirements.

904.6.2.3 System hoses.

System hoses shall be examined at 12-month intervals for damage. Damaged hoses shall be replaced or tested. At five-year intervals, all hoses shall be tested.

904.6.2.3.1 Test procedure.

Hoses shall be tested at not less than 2,500 pounds per square inch (psi) (17 238 kPa) for high-pressure systems and at not less than 900 psi (6206 kPa) for low-pressure systems.

904.6.2.4 System components.

System components, such as switches, door and window releases, interconnected valves, damper releases and supplementary alarms, shall be manually operated at 12-month intervals to ensure that such components are in proper operating condition.

904.6.3 Clean agent systems.

Clean agent systems shall be maintained in accordance with FC 901.6.1, 904.5, 904.6.3.1 and 904.6.3.2.

904.6.3.1 Containers.

The extinguishing agent quantity and pressure of the containers shall be checked at 6-month intervals. Where a container shows a loss in original weight of more than 5 percent or a loss in original pressure, adjusted for temperature, of more than 10 percent, the container shall be refilled or replaced. The weight and pressure of the container shall be recorded on a tag attached to the container.

904.6.3.2 System hoses.

System hoses shall be examined at 12-month intervals for damage. Damaged hoses shall be replaced or tested. All hoses shall be tested at 5-year intervals.

904.6.4 Dry chemical systems.

Dry chemical systems shall be maintained in accordance with FC 901.6.1, 904.5 and 904.6.4.1.

904.6.4.1. Additional maintenance requirements.

Extinguishing agent containers shall be weighed to verify the required amount of agent. Stored pressure-type units shall be checked for the required pressure. The cartridge of cartridge-operated units shall be weighed and replaced at intervals specified by the manufacturer.

904.6.5 Foam systems.

Foam systems shall be maintained in accordance with FC 901.6.1, 904.5 and 904.6.5.1.

904.6.5.1 Commercial cooking installations.

Foam fire extinguishing systems installed to protect a commercial cooking operation shall additionally comply with the requirements of FC 904.3.8.

904.6.6 Halon systems.

Lawfully existing halon systems shall be maintained in accordance with FC 901.6.1, 904.5 and 904.6.6.1 through 904.6.6.3. All other halon systems shall be removed in accordance with FC 904.1.4.2.

904.6.6.1 Containers.

The extinguishing agent quantity and pressure of containers shall be checked at least on a semiannual basis. Where a container shows a loss in original weight of more than 5 percent or a loss in original pressure (adjusted for temperature) of more than 10 percent, the container shall be refilled or replaced. The weight and pressure of the container shall be recorded on a tag attached to the container.

904.6.6.2 System hoses.

System hoses shall be examined at 12-month intervals for damage. Damaged hoses shall be replaced or tested. At 5-year intervals, all hoses shall be tested.

904.6.6.2.1 Test procedure.

For Halon 1301 systems, hoses shall be tested at not less than 1,500 psi (10 343 kPa) for 600 psi (4137 kPa) charging pressure systems and not less than 900 psi (6206 kPa) for 360 psi (2482 kPa) charging pressure systems. For Halon 1211 hand-hose line systems, hoses shall be tested at 2,500 psi (17 238 kPa) for high-pressure systems and 900 psi (6206 kPa) for low-pressure systems.

904.6.6.3 System components.

System components, such as switches, door and window releases, interconnected valves, damper releases and supplementary alarms, shall be manually operated at 12-month intervals to ensure such components are in proper operating condition.

904.6.7 Water mist systems.

Water mist systems shall be maintained in accordance with FC 901.6.1, 904.5 and NFPA 750, as modified by FC Appendix B.

904.6.8 Wet chemical systems.

Wet chemical systems shall be maintained in accordance with FC 901.6.1, 904.5 and 904.6.8.1 through 904.6.8.3.

904.6.8.1 Additional maintenance requirements.

Extinguishing agent containers shall be weighed to verify the required amount of agent. Stored pressure-type units shall be checked for the required pressure. The cartridge of cartridge-operated units shall be weighed and replaced at intervals specified by the manufacturer.

904.6.8.2 Fusible link maintenance.

Fixed temperature-sensing elements shall be maintained to ensure proper operation of the system.

904.6.8.3 Commercial cooking installations.

Wet chemical fire extinguishing systems installed to protect a commercial cooking operation shall additionally comply with the requirements of FC 904.3.8.

904.6.9 Commercial cooking systems.

Commercial cooking fire extinguishing systems shall be maintained in accordance with FC 609, 901.6.1, 904.5 and 904.6.9.1.

904.6.9.1 Fusible link and sprinkler head replacement.

Fusible links and foam water sprinkler heads shall be replaced at least annually, and other protection devices shall be serviced or replaced in accordance with the manufacturer's instructions.

Exception: Frangible bulbs are not required to be replaced annually.

904.6.10 Domestic cooking systems.

Fire extinguishing systems installed on domestic cooking hoods in Group I-2 occupancies, or in any other occupancy, shall be installed and maintained in accordance with FC 904.6.10.1 and 904.6.10.2.

904.6.10.1 Installation.

Such fire extinguishing systems shall be installed by a master fire suppression piping contractor, who shall certify to the department that the installation is in compliance with the construction codes and this code. Such certification shall be submitted to the department in the manner prescribed by the department.

904.6.10.2 Maintenance.

Such fire extinguishing systems shall be maintained in accordance with FC 901.6.1 and 904.5.