Does a 3M N95 mask have an expiration date?

Answer 1

The shelf life of 3M N95 respirators is 3 years from the date of manufacture if stored and transported under the following conditions:

1. Original packaging
2. Storage conditions between 4ºC to 50ºC
3. Relative Humidity not exceeding 90%
4. Packaging and all contents must remain dry, stored away from direct sunlight

To check on the expiry date of the respirator, please refer to the Lot Number printed on the respirator. If the Lot Number shows a number LOWER than XXXXX, the respirator is expired.

Answer 2

N95 respirators are typically manufactured from a polypropylene (PP) material which does not have any degradation in performance over time if stored in normal conditions. They do not expire. After a mask is removed from the box in which it is sold, it generally should be used within a day in order to avoid / minimize contamination from airborne particles which might settle on the inside surface of the exposed mask.