Labeling For Fire Extinguisher

Back in 1978 - 1990, I was a fire fighter. For a side job, I owned a small, local fire protection equipment service which included sales & service of portable fire extinguishers.

I recall something in the regs about "readily accessible". The extinguisher cant be blocked or immediately unavailable where you would have to use tools or gain access to it as being under objects & debris. It cant be locked etc unless its it in a locked cabinet when its easily accessible by, for example, breaking the glass to the cabinet etc. Something along those lines. I dont remember exactly.

I did a couple of quick google searches & didn't come up with anything related to trucks, but I did find some OSHA stuff, although not directly stating "trucks". Most of what I seen was related to buildings etc. If anyone wants to do some research on this for themselves or the OP, the regs for portable fire extinguishers is NFPA 10.
(That is the National Fire Prevention Association, section 10.)

Again, I haven't researched this either but someone who knows the FMCSA (DOT) rules may know where this is. If I remember correctly, the fire extinguisher in or on a truck has to be in a bracket & must be secured.

Hope this helps.