Impact of multiple consecutive donnings on filtering facepiece respirator fit

Published:August 24, 2011DOI:


      A concern with reuse of National Institute for Occupational Safety and Health–certified N95 filtering facepiece respirators (FFRs) is that multiple donnings could stress FFR components, impairing fit. This study investigated the impact of multiple donnings on the facepiece fit of 6 N95 FFR models using a group of 10 experienced test subjects per model.


      The TSI PORTACOUNT Plus and N95 Companion accessory were used for all tests. After qualifying by passing a standard Occupational Safety and Health Administration fit test, subjects performed up to 20 consecutive tests on an individual FFR sample using a modified protocol. Regression analyses were performed for the percentage of donnings resulting in fit factors (FFs) ≥100 for all 6 FFR models combined.


      Regression analyses showed statistical significance for donning groups 1-10, 1-15, and 1-20. The mean percentage of donnings with an FF ≥100 was 81%-93% for donning group 1-5, but dropped to 53%-75% for donning group 16-20.


      Our results show that multiple donnings had a model-dependent impact on fit for the 6 N95 models evaluated. The data suggest that 5 consecutive donnings can be performed before FFs consistently drop below 100.

      Key words

      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to American Journal of Infection Control
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


      1. Code of Federal Regulations. 42 CFR Part 84. Respiratory protective devices. 1995.

        • Cowling B.J.
        • Zhou Y.
        • Ip D.K.M.
        • Leung G.M.
        • Aiello A.E.
        Facemasks to prevent transmission of influenza virus: a systematic review.
        Epidemiol Infect. 2010; 138: 449-456
      2. Centers for Disease Control and Prevention. 2005 guidelines for preventing the transmission of Mycobacterium tuberculosis in health care settings, 2005. Available from: Accessed May 3, 2011.

      3. National Institute for Occupational Safety and Health. TB respiratory protection program in health care facilities: administrator’s guide. NIOSH publication 99-143, appendix G, 1999. Available from: Accessed May 3, 2011.

      4. National Institute for Occupational Safety and Health, National Personal Protective Technology Laboratory. Respirator trusted-source information page, 2010. Available from: Accessed May 3, 2011.

      5. Centers for Disease Control and Prevention. Interim guidance on infection control measures for 2009 H1N1 influenza in healthcare settings, including protection of healthcare personnel. Historical archive, 2009. Available from: Accessed May 3, 2011.

      6. Code of Federal Regulations. 29 CFR Part 1910.134. Respiratory protection, 1998. Available from: Accessed May 3, 2011.

      7. National Institute for Occupational Safety and Health. May 2, 1997, letter to all users of P-series particulate respirators: NIOSH service time recommendations for P-series particulate respirators. Available from: Accessed May 3, 2011.

        • Johnson B.
        • Winters D.R.
        • Shreeve T.R.
        • Coffey C.C.
        Respirator filter reuse test using the laboratory simulant Mycobacterium tuberculosis (H37RA strain).
        J Am Biol Safety Assoc. 1998; 3: 105-116
      8. Centers for Disease Control and Prevention. Questions and answers regarding respiratory protection for infection control measures for 2009 H1N1 influenza among healthcare personnel. Available from: Accessed May 3, 2011.

        • Institute of Medicine
        Reusability of facemasks during an influenza pandemic: facing the flu.
        National Academies Press, Washington [DC]2006
        • Campbell D.L.
        • Coffey C.C.
        • Jensen P.A.
        • Zhuang Z.
        Reducing respirator fit test errors: a multi-donning approach.
        J Occup Environ Hyg. 2005; 2: 391-399
        • Coffey C.C.
        • Campbell D.L.
        • Zhuang Z.
        Simulated workplace performance of N95 respirators.
        Am Indust Hyg Assoc J. 1999; 60: 618-624
        • Coffey C.C.
        • Lawrence R.B.
        • Campbell D.L.
        • Zhuang Z.
        • Calvert C.A.
        • Jensen P.A.
        Fitting characteristics of eighteen N95 filtering-facepiece respirators.
        J Occup Environ Hyg. 2004; 1: 262-271
        • Coffey C.C.
        • Lawrence R.B.
        • Zhuang Z.
        • Duling M.G.
        • Campbell D.L.
        Errors associated with three methods of assessing respirator fit.
        Occup Environ Hyg. 2006; 3: 44-52
        • Viscusi D.J.
        • Bergman M.S.
        • Novak D.A.
        • Faulkner K.A.
        • Powell J.B.
        • Palmiero A.J.
        • et al.
        Impact of three biological decontamination methods on filtering facepiece respirator fit, smell, comfort, and donning ease.
        J Occup Environ Hyg. 2011; 8: 426-436
      9. Food and Drug Administration. Masks and N95 respirators. Available from: Accessed May 3, 2011.

      10. TSI, Inc. Model 8095 N-95-Companion to the PORTACOUNT Plus, operation and service manual. P/N 1980308, revision H. Shoreview [MN]: TSI, Inc; 2005.

      11. Zhuang Z, Benson S, Lynch S, Palmiero A, Roberge R. Laboratory study to assess causative factors affecting temporal changes in filtering facepiece respirator fit, part I: pilot study. J Occup Environ Hyg. In press.

        • Da Roza R.A.
        • Cadena-Fix C.A.
        • Carlson G.J.
        • Hardis K.E.
        • Held B.J.
        Reproducibility of respirator fit as measured by quantitative fitting tests.
        Am Ind Hyg Assoc J. 1983; 44: 788-794
      12. Harris FS. Intra- and inter-subject variability of fit for a half-mask respirator. Master’s thesis, University of Alabama School of Public Health, 1990.

      13. Howells B. Inter-subject variability of fit for N-95 disposable particulate respirators. Master’s thesis, West Virginia University, Occupational Hygiene and Occupational Safety, Department of Industrial and Management Systems Engineering, 1997.

        • Grinshpun S.A.
        • Haruta H.
        • Eninger R.M.
        Performance of an N95 filtering facepiece particulate respirator and a surgical mask during human breathing: two pathways for particle penetration.
        J Occup Environ Hyg. 2009; 6: 593-603
        • Zhuang Z.
        • Coffey C.C.
        • Jensen P.A.
        • Campbell D.L.
        • Lawrence R.B.
        • Myers W.R.
        Correlation between quantitative fit factors and workplace protection factors measured in actual workplace environments at a steel foundry.
        Am Indust Hyg Assoc J. 2003; 64: 730-738