A study on the improvement of the fitting ratio for the N95 filtering facepiece respirators by attaching adjustable elastic head straps and a sweat-absorbent 3-D facepiece lip cushion for women under 40 years old

Fit testing is essential to find an N95 filtering facepiece respirator to fit one's face properly. However, it was suggested that for women under 40 years old, it was relatively difficult to find a properly fitted respirator. Thus, structural improvement of the N95 filtering facepiece respirators has been required. The aim of this study was to examine if the fitting ratio could be improve, for women under 40 years old, with adjustable head straps that go around one's neck and attach to the respirator near one's mouth and a sweat-absorbent 3-D facepiece lip cushion.

Twenty participants used two types of N95 filtering facepiece respirators: 1. with the adjustable head straps that go around one's neck and attach to the respirator near one's mouth and the sweat-absorbent 3-D facepiece lip cushion, and 2. with only elastic straps as a control. Participants were tested with a quantitative fit test using the Mask Fitting Tester Model MT-03TM. The permissible range of leakage rate was less than 5.0%.

All the participants achieved leakage rates of less than 5.0% with normal breathing for the N95 filtering facepiece respirators with the adjustable head straps near the mouth and the sweat-absorbent 3-D facepiece lip cushion. However, five participants had leakage rates over 5.0% with normal breathing using the N95 filtering facepiece respirators with elastic straps only.

The N95 filtering facepiece respirators with the adjustable elastic head straps near the mouth and the sweat-absorbent 3-D facepiece lip cushion were better fitted for women under 40 years old.