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Subchapter 7. General Industry Safety Orders
Group 27. Fire Protection
Article 162. Fixed Extinguishing Systems, Gaseous Agents

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§6181. Gaseous Systems.

(a) Scope and Application.
(1) Scope. This Section applies to all fixed extinguishing systems, using a gas as the extinguishing agent. These systems shall also comply with Article 160. In some cases, the gas may be in a liquid state during storage.
(2) Application. The requirements of Subsections (b)(5) and (b)(6) shall apply only to total flooding systems.
(b) General Requirements.
(1) When carbon dioxide extinguishing systems are provided they shall be designed, installed, inspected and maintained in an approved manner.
NOTE: For information on carbon dioxide extinguishing system design, installation, inspection and maintenance, consult the National Fire Protection Association's Standard on “Carbon Dioxide Extinguishing Systems”, NFPA 12, 2011 edition and/or your local jurisdiction fire department.
(2) In any proposed use of carbon dioxide where there is a possibility that employees may be trapped in, or enter into atmospheres made hazardous by a carbon dioxide discharge suitable safeguards shall be provided to insure prompt evacuation of and to prevent entry into such atmospheres and also to provide means for prompt rescue of any trapped personnel. Suitable safeguards include personnel training, warning signs, discharge alarms, predischarge alarms and breathing apparatus any one or more of which may be necessary for particular carbon dioxide extinguishing system installation.
(3) Agents used for initial supply and replenishment shall be of the type approved for the system's application. Carbon dioxide obtained by dry ice conversion to liquid is not acceptable unless it is processed to remove excess water and oil.
(4) Except during overhaul, the employer shall assure that the designed concentration of gaseous agents is maintained until the fire has been extinguished or is under control.
(5) Employees shall not be exposed to toxic levels of gaseous agent or its decomposition products.
(6) The employer shall assure that the designed extinguishing concentration is reached within 30 seconds of initial discharge except for Halon systems which must achieve design concentration within 10 seconds.
(7) The employer shall provide a distinctive pre-discharge employee alarm capable of being perceived above ambient light or noise levels when agent design concentrations exceed the maximum safe level for employee exposure. The pre-discharge employee alarm shall provide employees time to safely exit the discharge area prior to system discharge.
(8) Egress.
(A) Where egress from an area cannot be accomplished within one minute, the employer shall not use Halon 1301 in concentrations greater than 7 percent.
(B) Where egress takes greater than 30 seconds but less than one minute, the employer shall not use Halon 1301 in a concentration greater than 10 percent.
(C) Halon 1301 concentrations greater than 10 percent are only permitted in areas not normally occupied by employees provided that any employee in the area can escape within 30 seconds. The employer shall assure that no unprotected employees enter the area during agent discharge.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
1. New article 162 (section 6181) filed 9-8-81; effective thirtieth day thereafter (Register 81, No. 37).
2. Editorial correction of subsection (b)(1) filed 11-9-81; effective thirtieth day thereafter (Register 81, No. 45).
3. Amendment of subsection (b)(1) filed 9-6-83; effective thirtieth day thereafter (Register 83, No. 37).
4. Change without regulatory effect deleting title 24 reference (Register 87, No. 49).
5. New subsections (b)(4) and (b)(6) and subsection renumbering filed 5-17-93; operative 6-16-93 (Register 93, No. 21).
6. Amendment of subsection (b)(1) filed 12-2-2014; operative 1-1-2015 (Register 2014, No. 49).

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