The shelf life of a C50 mask remaining sealed in its original unopened packaging, correctly stored, is twenty years. Once opened and in use, mask components subject to ageing (especially valves) must be routinely replaced to maximise useful life. If any deterioration or damage is suspected to any component, replace immediately. See the user manual for component replacement intervals.
Below are links to all the Avon Protection FAQ's including product specific queries.
If you have any additional questions please email protection@avon-rubber.com