A review of mask fit testing data associated with protocols utilized in evaluating the efficacy of N95 masks for health care workers.

Background: Quantitative mask fit testing (QNFT) is the gold standard to confirm the correct fit of a N95/P2 mask to ensure health care workers protection from airborne viruses. Using the Occupational Safety and Health Administration (OSHA) guidance indicates a final fit test result is a cumulative score derived from manoeuvres within the OSHA protocol. The protocol-based manoeuvres mimic aspects of clinical care by health professionals and mask fit testing is conducted to provide protection from airborne viruses and pollutants within a care setting.

Objectives: To determine whether studies undertaking QNFT report the results of individual manoeuvres of the OSHA protocol.

Methods: A comprehensive search strategy for the systematic review was developed to determine eligible studies, published between May 2011 and May 2021. Two researchers independently screened all full text articles retrieved and all disagreements were resolved through discussion.

Results: The search found 557 studies. After removing 119 duplicates, 437 articles were reviewed based on title and abstract, 411 studies were excluded. Twenty-seven full text articles were assessed for eligibility, all were excluded for the following reasons: study did not report the results of the long or short OSHA protocol (12), study did not assess mask fit using the long or short OSHA protocol (10), article type (discussion/commentary/editorial) or wrong study type (1). Despite the use of very broad search terms no eligible studies were found and the result was declared an empty review.

Conclusion: Internationally accepted QNFT protocols have a number of manoeuvres that reflect health care workers' physical movements during the delivery of clinical care. Studies of mask fit testing appear to lack the reporting of outcomes for each manoeuvre with only the cumulative results being provided. This finding raises the need to understand potential risk from a mask leak during the delivery of clinical care as evidenced by failing a manoeuvre during mask fit testing. Further research is required to understand the importance of passing each mask fit testing manoeuvre and the relationship to airborne protection during the delivery of clinical care.