Which of the following limitations is correct regarding gas or filter masks?

Correct Answer: Option C — A canister is reliable for up to 5 years from the date of manufacture, as long as the seal is unbroken.

Gas mask canisters contain chemical sorbents that degrade over time, even when stored. Manufacturers specify a shelf life, typically five years, provided the factory seal remains intact. Once the seal is broken, the canister must be discarded according to the manufacturer's instructions to ensure reliable protection against hazardous vapors.