Building Code Board of Appeals Agenda and Packet 2009 06 18

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some additional safeguards to the occupants, they don't reduce the required fire flow, amount of fire pumps, or personnel required to extinguish the fire. Currently, the ICC code allows a wood frame structure to be anywhere from 9,000 sq. fL for Type V (B) to 18,000 sq. ft. for Type V (A) before automatic sprinklers are required. This being one of the more common types of construction for small and mid-size businesses, it was picked to be used as one example. Using this type of construction and an area of 10,000 sq. fl. we can develop a sample of required fire flow. Using the current ICC fire code, it is estimated that the basic fire flow for this structure would be 2,750 gpm to provide fire fighting in this sample structure. This demand occurs because a fire could consume contents and possibly structural members before its propagation (fire spread) is interrupted by fire suppression personnel. A standard hose line for large fires flow is approximately 250 gpm, and when divided into 2,750 gpm equates to eleven hose streams. Generally accepted fire service practice uses a minimum of three firefighters per 250 gpm hose line. 11 hose lines x 3 firefighters = 33 firefighters, plus additional personnel for other jobs. If the sample structure were to be protected by an automatic sprinkler system the fire flow could be reduced by as much as 50%. It would now require approximately 1,375 gpm instead of2,750 gpm. By using the previously described example, divide 1,375 gpm by 250 which would equal six hose lines. 6 hose lines x 3 firefighters = 18, plus additional personnel for other jobs (e.g., rescue, ventilation, and laddering). This simple analysis identifies that every structure protected by automatic fire sprinklers could reduce the required fire flow and perhaps more importantly, help our volunteer department safely and effectively mitigate a fire in a commercial structure. Moreover, there are additional arguments for reduced manpower for these types of fires. Currently. NFPA 1710 (standards for organization and fire suppression deployment) requires a minimum of 14 firefighting personnel respond to all initial alarms or residential structure fires. So then it sumds to reason that structures larger than a typical house fire require a significantly larger commitment of resources. Moreover, since the LFD is predominately a volunteer department, it is a challenge to amass the necessary initial resources to safely mitigate these types of larger fires. If we were to use our sample structure, change it to Type Il-B (fire resistive) construction, and apply the NrPA standards for fire flow reductions at sprinkle red properties, we can take up to a 75% reduction in fire flows. Using the sample formula listed above. the basic fire flow will be 2,250 gpl1l. Assuming the sample structure meets all the requisite building requirements, our new fire flow could then be 562.5 gpm. By dividing 562.5 gpm by 250 gpm nozzle flow, you obtain 2.25 hose lines x 3 firefighters = approximately 7 firefighters, plus a 1/3 increase for other johs (e.g.. ventilation.laddering, and rescue), which equals approximately 10 firefighters. The use of automatic fire sprinkler protection to control fire relates to more than just personnel and equipment. The ability to control fire often extends heyond the ability of fire suppression systems because the time of discovery and the rapidity of flame spread is often uncontrolled. Considering these possibilities, analysis indicates that any size structure could be subject to heavy or total fire loss regardless offire department size. This should be given equal or greater consideration than personnel demand. This initiative is only a part of our overall analysis and recommendation for improvement to our community fire defense programs. Some other factors include: fire station locations, sUlffing and skills mix, volunteer resource availability, apparatus types and capabilities - in addition to other structural modifications such as compartmentation.