Impact of Three Biological Decontamination Methods on Filtering Facepiece Respirator Fit, Odor, Comfort, and Donning Ease

Abstract

The objective of this study was to determine if ultraviolet germicidal irradiation (UVGI), moist heat incubation (MHI), or microwave-generated steam (MGS) decontamination affects the fitting characteristics, odor, comfort, or donning ease of six N95 filtering facepiece respirator (FFR) models. For each model, 10 experienced test subjects qualified for the study by passing a standard OSHA quantitative fit test. Once qualified, each subject performed a series of fit tests to assess respirator fit and completed surveys to evaluate odor, comfort, and donning ease with FFRs that were not decontaminated (controls) and with FFRs of the same model that had been decontaminated. Respirator fit was quantitatively measured using a multidonning protocol with the TSI PORTACOUNT Plus and the N95 Companion accessory (designed to count only particles resulting from face to face-seal leakage). Participants' subjective appraisals of the respirator's odor, comfort, and donning ease were captured using a visual analog scale survey. Wilcoxon signed rank tests compared median values for fit, odor, comfort, and donning ease for each FFR and decontamination method against their respective controls for a given model. Two of the six FFRs demonstrated a statistically significant reduction (p< 0.05) in fit after MHI decontamination. However, for these two FFR models, post-decontamination mean fit factors were still ≥ 100. One of the other FFRs demonstrated a relatively small though statistically significant increase (p < 0.05) in median odor response after MHI decontamination. These data suggest that FFR users with characteristics similar to those in this study population would be unlikely to experience a clinically meaningful reduction in fit, increase in odor, increase in discomfort, or increased difficulty in donning with the six FFRs included in this study after UVGI, MHI, or MGS decontamination. Further research is needed before decontamination of N95 FFRs for purposes of reuse can be recommended.

Cleaning of filtering facepiece respirators contaminated with mucin and Staphylococcus aureus

“…Heimbuch et al 4 and Lore et al 5 demonstrated 3 energetic decontamination methods—microwave-generated steam, low-temperature moist heat, and ultraviolet germicidal irradiation—that inactivate H1N1 and H5N1 influenza viruses without significantly affecting FFR fit or function. 6,7 Other chemical and energetic methods have also shown promise for decontamination of FFRs, 8–10 but we found no studies that addressed decontamination of bacterial agents on FFRs.…”

Selecting models for a respiratory protection program: What can we learn from the scientific literature?

“…Viscusi et al 36 collected participants’ responses to several subjective criteria in a study of effects of decontamination on 6 FFR models. The following FFRs were used in the study: 3M 8000, 3M 8210, Moldex 2200N95 (Moldex-Metric, Culver City, CA), 3M 1860, 3M 1870, and Kimberly-Clark PFR95-270 (Kimberly-Clark, Roswell, GA).…”

Simulated Effects of Head Movement on Contact Pressures Between Headforms and N95 Filtering Facepiece Respirators-Part 1: Headform Model and Validation

“…This study did not consider lateral bending because the respirator fit test does not require lateral bending movement (OSHA, 1999; Viscusi et al ., 2011). The total head movements were the summation of seven relative movements of C0–C1 to C6–C7.…”