Effectiveness of surgical masks against influenza bioaerosols

Published:March 18, 2013DOI:



      Most surgical masks are not certified for use as respiratory protective devices (RPDs). In the event of an influenza pandemic, logistical and practical implications such as storage and fit testing will restrict the use of RPDs to certain high-risk procedures that are likely to generate large amounts of infectious bioaerosols. Studies have shown that in such circumstances increased numbers of surgical masks are worn, but the protection afforded to the wearer by a surgical mask against infectious aerosols is not well understood.


      To develop and apply a method for assessing the protection afforded by surgical masks against a bioaerosol challenge.


      A dummy test head attached to a breathing simulator was used to test the performance of surgical masks against a viral challenge. Several designs of surgical masks commonly used in the UK healthcare sector were evaluated by measuring levels of inert particles and live aerosolised influenza virus in the air, from in front of and behind each mask.


      Live influenza virus was measurable from the air behind all surgical masks tested. The data indicate that a surgical mask will reduce exposure to aerosolised infectious influenza virus; reductions ranged from 1.1- to 55-fold (average 6-fold), depending on the design of the mask.


      We describe a workable method to evaluate the protective efficacy of surgical masks and RPDs against a relevant aerosolised biological challenge. The results demonstrated limitations of surgical masks in this context, although they are to some extent protective.


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        • Tellier R.
        Review of aerosol transmission of influenza A virus.
        Emerg Infect Dis. 2006; 12: 1657-1662
        • Wilde J.A.
        • McMillan J.A.
        • Serwint J.
        • Butta J.
        • O’Riordan M.A.
        • Steinhoff M.C.
        Effectiveness of influenza vaccine in health care professionals: a randomized trial.
        JAMA. 1999; 28: 908-913
        • Govorkova E.
        • Ilyushina N.
        • McClaren J.
        • Naipospos T.
        • Douangngeun B.
        • Webster R.
        Susceptibility of highly pathogenic H5N1 influenza viruses to the neuraminidase inhibitor oseltamivir differs in vitro and in a mouse model.
        Antimicrobial Agents Chemother. 2009; 53: 3088-3096
        • Garner J.S.
        Guideline for isolation precautions in hospitals. The Hospital Infection Control Practices Advisory Committee.
        Infect Control Hosp Epidemiol. 1996; 17: 53-80
        • Daugherty E.L.
        • Branson R.D.
        • Deveraux A.
        • Rubinson L.
        Infection control in mass respiratory failure: preparing to respond to H1N1.
        Crit Care Med. 2010; 38: e103-e109
        • Oberg T.
        • Brosseau L.M.
        Surgical mask filter and fit performance.
        Am J Infect Control. 2008; 36: 276-282
        • ASTM International. ASTM F 1862-07
        Standard test method for resistance of medical face masks to penetration by synthetic blood (horizontal projection of fixed volume at a known velocity).
        ASTM, West Conshohocken, PA2007
        • Health Protection Agency
        Infection control precautions to minimise transmission of seasonal influenza in the healthcare setting, 2011–2012.
        HPA, London2012
        • Siegel J.D.
        • Rhinehart E.
        • Jackson M.
        • Chiarello L.
        • the Healthcare Infection Control Practices Advisory Committee
        2007 Guideline for isolation precautions: preventing transmission of infectious agents in healthcare settings.
        Centers for Disease Control and Prevention, Atlanta2007
        • Advisory Committee on Dangerous Pathogens
        Biological agents: managing the risks in laboratories and healthcare premises.
        Bootle: Health and Safety Executive. 2005;
        • Health and Safety Executive
        Respiratory protective equipment at work: a practical guide.
        3rd ed. HSE, Bootle2005
        • Rengasamy A.
        • Zhuang Z.
        • Berryann R.
        Respiratory protection against bioaerosols: literature review and research needs.
        Am J Infect Control. 2004; 32: 345-354
        • Derrick J.L.
        • Gomersall C.D.
        Protecting healthcare staff from severe acute respiratory syndrome: filtration capacity of multiple surgical masks.
        J Hosp Infect. 2005; 59: 365-368
        • Derrick J.L.
        • Li P.T.
        • Tang S.P.
        • Gomersall C.D.
        Protecting staff against airborne viral particles: in vivo efficiency of laser masks.
        J Hosp Infect. 2006; 64: 278-281
        • Lawrence R.B.
        • Duling M.G.
        • Calvert C.A.
        • Coffey C.C.
        Comparison of performance of three different types of respiratory protection devices.
        J Occup Environ Hyg. 2006; 3: 465-474
        • Tuomi T.
        Face seal leakage of half masks and surgical masks.
        Am Ind Hyg Assoc J. 1985; 46: 308-312
        • Dreller S.
        • Jatzwauk L.
        • Nassauer A.
        • Paszkiewicz P.
        • Tobys H.-U.
        • Rüden H.
        Investigations on suitable respiratory protection against airborne pathogens.
        Gefahrstoffe – Reinhaltung der Luft. 2006; 66: 14-24
        • Wake D.
        • Bowry A.
        • Crook B.
        • Brown R.
        Performance of respirator filters and surgical masks against bacterial aerosols.
        J Aerosol Sci. 1997; 28: 1311-1329
        • MacIntyre C.R.
        • Wang Q.
        • Cauchemez S.
        • et al.
        A cluster randomized clinical trial comparing fit-tested and non-fit-tested N95 respirators to medical masks to prevent respiratory virus infection in health care workers.
        Influ Other Respir Vir. 2011; 5: 170-179
        • Bischoff W.E.
        • Reid T.
        • Russell G.B.
        • Peters T.R.
        Transocular entry of seasonal influenza-attenuated virus aerosols and the efficacy of n95 respirators, surgical masks, and eye protection in humans.
        J Infect Dis. 2011; 204: 193-199
        • Weber A.
        • Willeke K.
        • Marchioni R.
        • et al.
        Aerosol penetration and leakage characteristics of masks used in the health care industry.
        Am J Infect Control. 1993; 21: 167-173
        • Chen S.K.
        • Vesley D.
        • Brosseau L.M.
        • Vincent J.H.
        Evaluation of single-use masks and respirators for protection of health care workers against mycobacterial aerosols.
        Am J Infect Control. 1994; 22: 65-74
        • McCullough N.V.
        • Brosseau L.M.
        • Vesley D.
        Collection of three bacterial aerosols by respirator and surgical mask filters under varying conditions of flow and relative humidity.
        Ann Occup Hyg. 1997; 41: 677-690
        • Qian Y.
        • Willeke K.
        • Grinshpun S.A.
        • Donnelly J.
        • Coffey C.C.
        Performance of N95 respirators: filtration efficiency for airborne microbial and inert particles.
        Am Ind Hyg Assoc J. 1998; 59: 128-132
        • Balazy A.
        • Toivola M.
        • Adhikari A.
        • Sivasubramani S.K.
        • Reponen T.
        • Grinshpun S.A.
        Do N95 respirators provide 95% protection level against airborne viruses, and how adequate are surgical masks?.
        Am J Infect Control. 2006; 34: 51-57
        • Yassi A.
        • Moore D.
        • Fitzgerald J.M.
        • Bigelow P.
        • Hon C.Y.
        • Bryce E.
        Research gaps in protecting healthcare workers from SARS and other respiratory pathogens: an interdisciplinary, multi-stakeholder, evidence-based approach.
        J Occup Environ Med. 2005; 47: 41-50
        • Gaush C.R.
        • Smith T.F.
        Replication and plaque assay of influenza virus in an established line of canine kidney cells.
        Appl Microbiol. 1968; 16: 588-594
        • Cann A.J.
        Virus culture: a practical approach.
        Oxford University Press, Oxford1999 (212–213)
        • British Standards Institution. BS EN 136:1998
        Respiratory protective devices: full face masks – requirements, testing, marking.
        BSI, London1998
        • International Standards Organisation. ISO 8996:2004
        Ergonomics of the thermal environment – determination of metabolic rate.
        ISO, Geneva2004
        • Health and Safety Executive
        Fit testing of respiratory protective equipment facepieces.
        HSE, Bootle2004