well you seem to know more on the topic than I do (not being sarcastic), how do the out-of-date filters perform? I've got a couple that expired in the early 90's that I'm not sure if they're safe to use (if I needed them) but I didn't want to throw them away until I knew for sure that they were unsafe/ineffective. (I have one less filter than masks because I shot one filter to shit during my only negligent discharge, lol)
I'll summarize the info I've recently read......
If the seals have been broken on a canister and it has sat around for some time (weeks? months?), it will be virtually useless in a lethal environment. It may offer some protection from tear gas, and is still good for dust and particulate filtration. NEVER BREAK THE SEALS UNTIL USE IS IMMINENT.
If the seals are still intact, they will still offer protection after the expiration date, but the length of time it protects decreases the longer it has been expired. An example I saw was a sealed canister that expired in the late 80's that is rated for 8 hours in a moderate exposure environment, would now offer only 2-3 hours of protection.
Here is a copy & paste warning about specific military surplus canisters:
FILTER: AMERICAN C2 (check exp. date) & C2A1
STATUS: EXPIRED -If more than 10 years old
** (old filters are known to have Chromium Toxicity
** and are considered highly dangerous)
DETAILS: To find out if your filter is expired, you must find the printed date of manufacture. Look for the serial number on the can: For Example: RFT 920000CF24054 (sample serial #) (first 2
digits are the year of manufacture) In this example the mfg date:
RFT [92] is 1992 These are 100% military surplus filters. The
military discontinued use of the C2 in favor of the new/better
C2A1 filters. But Caution: C2A1 filters provide no protection
against ammonia based agents.
