Suitability survey on N95 filter masks for public health emergency personnel / 上海预防医学

ABSTRACT

Objective To assess the suitability of N95 masks for public health emergency personnel. To compare the consistency between mask fit test result and subjective evaluation of mask-wearing air tightness so as to guide scientific selection and use of protection masks for emergency personnel. Methods By ambient aerosol condensation nuclear counter method, the quantitative fit test was done among 235 public health emergency personnel from both Municipal and District disease control centers. Questionnaires were conducted among them for investigation and comparison of their subjective evaluation of mask-wearing air tightness and mask fit test results. Results Of the 235 subjects , 160 passed the fittest with the pass rate being 68.1%. With various wearing actions for the test, the subjective evaluation for mask-wearing air tightness was compared with the fit test pass rate in terms of consistence, the kappa value range being from −0.09 to 0.43. K value of the action 5 (loudly speaking) was above 0.4, while the k values of other 6 actions were all below 0.4. Both Kappa value (0.09) and consistency rate (49.7%) were the lowest for action 8 (normal breathing) among all test actions. Conclusion The accuracy of the subjective evaluation for mask-wearing air tightness proves to be poor, unable to reflect the true protective effect and substitute for the fit test. It is advised that the public health personnel should rely on the fit test results to correctly choose and use suitable respiratory protective products.