Fit Abilities and Usability of Standard and Alternative Respirators for Small Face Health Workers in Thailand

Kansuda  Bootsri; Phanumas Krisorn

Authors

Kansuda Bootsri Occupational Medicine Resident, Faculty of Medicine, Khon Kaen University
Phanumas Krisorn Department of Community, Family, and Occupational Medicine, Faculty of Medicine, Khon Kaen University

Keywords:

N95, KN95, KF94, fit abilities, usability

Abstract

Objective: To evaluate the fit abilities and usability of a NIOSH-approved N95, certified KN95, and KN94 respirators with a hook among Thai health workers who typically have small faces. Methods: A descriptive study was conducted involving 47 Thai health workers with small facial dimensions, as defined by the NIOSH Bivariate Panel. The study assessed the fit abilities and usability of both standard and alternative respirators, including the NIOSH-approved N95 respirator, as well as the KN95 and KF94 respirators, which are certified. Results: The mean ± standard deviation fit factor values for each type of respirator were as follows: N95 = 125.9 ± 60.8, KN95 = 18.9 ± 8.53, and KF94 = 27.9 ± 22.7. In the fit criteria assessment, 61.7% of participants rated the N95 as providing a well-fitted feeling, compared to 14.9% for the KN95 and 12.8% for the KF94. In terms of comfortability, 42.6% of participants rated the N95 as the most comfortable, followed by 29.8% for KF94 and 25.6% for KN95. For breathability, 83.0% rated KF94 as the most breathable, followed by 72.3% for KN95 and 63.8% for N95. Conclusions: Only the N95 respirator passed the fit test and demonstrated appropriate fit abilities, including the highest rate of perceived well-fit feeling. In terms of usability, the N95 was rated as the most comfortable, while the KF94 was identified as the most breathable.

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