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.