In 1992 we were given a 1972
Avon 6 man
liferaft in a canister which had NEVER been repacked.
We were getting ready to sail to
Mexico, so long story short, we had it repacked by a place in South
Seattle.
They replaced the foot
pump for the raft, the
water, the SOLAS flares etc.
When we picked it up we asked, "What happens to old SOLAS flares?
They said they had to pay big
money to get rid of them at a hazardous waste site (run of course by King County Gummint, but I won't go there).
I asked if they would fire, being so old, and he said he'd be very surprised if there was even ONE dud in the whole bunch.
I asked if I could keep the old ones as spares, and he was glad to oblige.
At the time we were the Commodores of our local
cruising club, so I asked if he had any more he'd want to give me for the club.
I ended up with a 2'x2' box of them which we gave away at the next
cruising club meeting.
We fired off our 1972 parachute flares at the next 4th of July fireworks display and every one of them performed as expected, PERFECT !
After 9/11, your access to these may be not as good...