Only a guess, but I suspect that DOT - like FAA - has concentrated on ignition prevention and can't see the forest for all the one-track trees they're looking at within their field of view - which may be limited by the blinders they seem to wear.

FAA has begun to examine "snuff" methods e.g. foam cells and nitrogen-inerting systems, etc. since the '96 TWA flight that exploded and crashed:

Federal Register

Someday someone <img src="/forums/images/graemlins/sleeping.gif" alt="" /> at DOT may have one of those Eureka! moments. <img src="/forums/images/graemlins/scared.gif" alt="" />

Frank

'89 [color:"white"]G-Raider[color:"white"] [color:"black"]Supercharged 3.0L, MegaSquirt 2, lockup A/T, 2.5" exhaust, 172k, Cibie H4s/Oscar SCs, Hella Micro DE fogs, Cobra CB, Superwinch hubs, LSD rear/Aussie Locker front, Bilsteins, Lifeline AGM, Rust-Oleum