Performance of N95 Filtering Facepiece Respirators Used with Skin Protectants: Manikin-based Study

XINYI NIU, Sergey A. Grinshpun, Michael Yermakov, Roman Jandarov, Iliya Rivkin, University of Cincinnati

     Abstract Number: 574
     Working Group: Health-Related Aerosols

Abstract
Continuous wearing of N95 filtering facepiece respirators (FFRs) during the COVID-19 pandemic have often led to adverse skin conditions, such as dryness/tightness and scaling. Skin protectants are widely used to reduce or avoid these impairments. A recent study conducted by our research group explored whether wearing skin protectants impacts the performance of FFRs; however, the above-mentioned study involved human subjects and as such generated results which were affected by the individual variability.

As an alternative, a standardized protocol was deployed, utilizing the NIOSH advanced static manikin headform connected to Breathing Recording and Simulation System to simulate a sinusoidal breathing pattern. The tests were performed using three N95 FFRs (3M 8210, 3M 1870+, and AOSafety 1050), five skin protectants (two fabric tape-like and three gel/cream-like) and two breathing flow rates (30 and 85 L/min). The Total Inward Leakage (TIL) was quantified as the ratio of the aerosol concentrations measured inside and outside the respirator. The aerosolized particles of NaCl served as the challenge aerosol.
This investigation revealed that the TIL value was significantly affected by the interaction of the three variables such as a skin protectant type, breathing flow rate and an FFR model. The data suggest that various types of skin protectants may impact the TIL differently, by either increasing or decreasing the TIL value. Either tape- or gel/cream-type protectants may improve the performance of both tested 3M FFRs as quantified by the TIL; however, when testing with AOSafety 1050 FFR, a negative effect of a skin protectant on the respirator performance was found for either group. The data obtained in this effort will help establish appropriate respiratory protection protocols for healthcare professionals and other individuals wearing respirators with skin protectants.