Aerosol penetration and leakage characteristics of masks used in the health care industry

Am J Infect Control. 1993 Aug;21(4):167-73. doi: 10.1016/0196-6553(93)90027-2.


Background: Historically, surgical masks have been worn to protect patients from being infected by large, pathogen-containing aerosol droplets emitted by health care personnel. Today, emphasis has shifted from solely protecting the patient to protecting the health care worker as well. As a result of new procedures used in operating rooms and clinical areas, aerosolized hazardous agents in the submicrometer size range are being produced, posing a potential threat to health care workers.

Methods: Eight surgical masks were tested for aerosol particle penetration through their filter media and through induced face-seal leaks.

Results: The percentage of filter penetration ranged from 20% to nearly 100% for submicrometer-sized particles. In comparison, a dust-mist-fume respirator used in industrial settings had significantly less penetration through its filter medium. When the surgical masks had artificially induced face-seal leaks, the concentration of submicrometer-sized particles inside the mask increased slightly; in contrast, the more protective dust-mist-fume respirator showed a fourfold increase in aerosol penetration into the mask with an artificial leak 4 mm in diameter.

Conclusion: We conclude that the protection provided by surgical masks may be insufficient in environments containing potentially hazardous submicrometer-sized aerosols.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aerosols*
  • Evaluation Studies as Topic
  • Filtration
  • Humans
  • Infection Control
  • Infectious Disease Transmission, Patient-to-Professional / prevention & control*
  • Masks / standards*
  • Particle Size
  • Personnel, Hospital


  • Aerosols