![]() Before the new standard, 5 lb, 6 lb, 10 lb, and even 20 lb capacity extinguishers were being manufactured without a hose assembly, using only a fixed nozzle. Having a hose on an extinguisher makes it very difficult to hold the extin- guisher in any other position than upright, and makes it easy to properly direct the discharge of agent. After this testing, “ ANSI/UL 299, Standard for Dry Chemical Fire Extinguishers” as referenced in “NFPA 10 Standard for Portable Fire Extinguishers,” was revised to require any extinguisher weighing more than 12 lb (gross weight), having a 2A rating and/or 20B rating or higher, to use a hose. A novice operator tended to grab the bottom of an extinguisher and tilt or invert it, resulting in an ineffective discharge. Testing showed that many novice operators had trouble keeping the extin- guisher upright when it did not have a discharge hose and nozzle. ![]() These tests concluded that changes in fire extinguisher design were needed in order to better assure proper opera- tion by novice operators. Dry chemical stored pressure extinguishers manufactured prior to October 1984 shall be removed from service at the next 6-year maintenance interval or the next hydrotest interval, whichever comes first.” In the late 1970s, UL, along with the NFPA 10 committee and some fire extinguisher manufacturers, conducted a series of fire tests with novice opera- tors.
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