We analyzed four years of N95 respirator quantitative fit test data collected from September 2013 onwards. In total, 165 tests had been performed, and 81/88 (92%) workers passed using at least one of the four different kinds of respirators available. However, the pass rate for each of the respirators ranged from 46%–82% and differed between genders. At the first step of the fit testing procedure, 64% of all failed respirator mask fit tests already exhibited air leakage. This high failure rate may indicate the poor reliability of the user self-seal check. Indeed, 28% of all respirator mask fit tests that passed exhibited air leakage during at least one step of the fit testing procedure. Air leakage was particularly common during the exercise that required bending over. However, a few of the respirators had little to no air leakage during the fit testing. Medical facilities should offer multiple kinds of respirator masks to healthcare providers to ensure a high pass rate on fit testing.