Preferred Citation: Cheit, Ross E. Setting Safety Standards: Regulation in the Public and Private Sectors. Berkeley:  University of California Press,  c1990 1990. http://ark.cdlib.org/ark:/13030/ft8f59p27j/


 
Four Standards for Aviation Fire Safety

Technical Objections and a Final Rule

The other technical objections to the proposed FAA standard concerned either the fire extinguishant or the nozzle configuration. Several manufacturers argued that Halon 1301 should be permitted in addition to


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Halon 1211.[20] Halon 1211 discharges in a more liquid state than Halon 1301 and has better range and direction in use. But Halon 1301 is considerably less toxic than 1211, so it may be advantageous in small areas such as the cockpit. The use of Halon 1301 in hand-held fire extinguishers is relatively recent. There were no hand-held Halon 1301 extinguishers when the FAA issued its general notice in 1980. Three years later, Metalcraft, Inc., received Factory Mutual Research Corporation's first approval for such a product. UL still did not list any. So there was limited information about the merits of this technical question.

The FAA balked and refused to consider the Halon 1301 alternative because, according to an FAA rulemaking staff member, "1301 is not rated for a Class A fire." The reference is to the UL method for rating fire extinguishers by type of fire and extinguisher capacity.[21] But the reasoning is flawed because UL's Class A fire is simply too big. "Halon is effective on an 'A' fire," notes a fire protection engineer, "but the smallest 'A' fire [that UL builds] takes about nine pounds of agent." Hand-held extinguishers usually have three to five pounds. There may be technical reasons for restricting the use of Halon 1301, particularly in large cabin spaces, where it might be less effective than Halon 1211, but the reason offered by the FAA indicates no understanding of these issues.

A few commenters suggested that the FAA require flexible discharge hoses on all fire extinguishers. This would be particularly helpful in battling fires in concealed spaces, overhead, or under the seats. Fixed nozzles, which are supposed to be operated in an upright position, are difficult to operate under such circumstances. Tests conducted by one airline suggested that flexible nozzles increased effectiveness by an incredible magnitude of ten. The FAA showed little interest in this issue. The rule was published in final form less than four months after the comment period closed. There was only one significant change: smoke detectors would not be required in the galley. This eliminated the airlines' strongest objection without compromising on anything the staff considered critical. The safety record with galley fires was far more reassuring than the record for lavatories. There has never been a catastrophic in-flight fire, domestic or foreign, that originated in the galley. While this requirement was easily dropped, addressing the other objections raised in the comment period was not so easy. They called for changes in specific requirements and would require additional analysis. The FAA had no patience for these arguments. The agency wanted to placate Congress and get the rule published. The rulemaking staff had


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no intention of letting public comments delay the process. The candid explanation of a staff member about comments concerning the value of requiring a flexible hose on Halon extinguishers illustrates the attitude: "There probably is a lot of benefit in a flexible hose. But we have a certain practical limitation here: we can't just go ahead in the middle of a rule action and change our minds and say that when the rule comes out we want twenty-five hundred airplanes to be equipped with flexible hoses. That throws everything into a cocked hat…. We had to make a decision and we made it." The rule was finalized in record time. It was promulgated on March 29, 1985, less than ten months after it was first proposed. Three years later, the FAA banned smoking on all domestic flights of under two hours. This may be the most cost-effective move the FAA could take toward reducing the risk of a cabin fire. The ban was adopted for health reasons, however, not for reasons of fire safety.


Four Standards for Aviation Fire Safety
 

Preferred Citation: Cheit, Ross E. Setting Safety Standards: Regulation in the Public and Private Sectors. Berkeley:  University of California Press,  c1990 1990. http://ark.cdlib.org/ark:/13030/ft8f59p27j/