Oxidizers, such as those used for treating swimming pools, have specific requirements for storage and fire protection. These requirements can be found in NFPA 43A, 1990 Edition, Code for the Storage of Liquid and Solid Oxidizers. It is important to know that using the wrong type of portable fire extinguisher on certain oxidizers could result in a violent reaction or explosion.
NFPA 43A contains the following paragraph:
2-11.4* Manual Fire Fighting. Manual fire fighting equipment in the form of portable water fire extinguishers or water hose reel stations shall be provided in accordance with the requirements of NFPA 10, Standard for the Installation of Portable Fire Extinguishers and NFPA 14, Standard for the Installation of Standpipe and Hose Systems.
Note 1: The placement and use of multipurpose dry chemical extinguishers (Class A:B:C) is specifically prohibited in areas where oxidizers that can release chlorine are stored.
Note 2: Halon extinguishers shall not be used in areas where oxidizers are stored.
The following paragraph from Appendix of NFPA 43A contains additional information on what extinguishing agents should not be used:
A-2-11.4 Do not use an A:B:C type dry chemical fire extinguisher on chlorine-containing oxidizers. The reaction between the oxidizer and the ammonium salts in the fire extinguishing agent may produce an explosive compound (NCl3). Carbon Dioxide or other agents that depend on their smothering action for effective use will be of no value in extinguishing fires involving ozidizers. Halon extinguishers should not be used on fires involving oxidizers because they may react with the oxidizer.
It is apparent from the above excerpts that the “agent of choice” for fighting fires involving oxidizers is WATER. In fact NFPA 43A states that “portable water fire extinguishers or water hose reel stations shall be provided.” There really isn’t any choice, the agent shall be water. This is certainly a perfect application for the Model 272NM Water Mist extinguisher. Remember that choosing the wrong type of extinguishing agent could be disastrous.
Your customers that use or store oxidizers should consider that the hazards of oxidizers may manifest themselves in one or more of the following hazardous situations:
1. They increase the burning rate of combustible material.
2. They may cause spontaneous ignition of combustible materials.
3. They may decompose and may liberate hazardous gases.
4. They may undergo self-sustained decomposition, which may result in an explosion.