Stockpiled N95 respirator/surgical mask release beyond manufacturer-designated shelf-life: a French experience.

ABSTRACT

BACKGROUND: To reduce the shortage of N95 respirators and surgical masks during the COVID-19 pandemic, stockpiled equipment beyond its expiry date could be released. AIM: Centralized testing of batches of expired surgical masks and N95 for safe distribution to hospital departments saving users time. METHODS: Tests of compliance with health authority directives were developed and carried out on 175 batches of N95 masks and 31 batches of surgical masks from 12th March 2020 to 16 April 2020. Five quality-control tests were performed on batch samples to check packaging integrity, mask appearance, breaking strength of elastic ties and strength of nose clip test, and face-fit. FINDINGS: Forty-nine per cent of FFP2 mask batches were compliant with directives, 32% of batches were compliant but with some concerns and 19% of batches were non-compliant. For surgical masks, 58% of batches were compliant, 39% of batches compliant but with concerns and 3% of batches were non-compliant. CONCLUSION: The main areas of non-compliance were the breaking strength of the elastic ties and the nose clip but these alone were not considered to make the masks unacceptable. Only mask appearance and face-fit results were decisive non-compliance criteria.