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Do cloth or surgical masks protect against wildfire smoke?

Dr. Colin Little

Dr. Colin Little

MD, FAWM, Chief Medical Officer, GOES Health

The short answer

Not well. Cloth face coverings should not be relied on for wildfire smoke, and surgical or one-strap masks don't seal to your face, so they give only limited protection. What actually works against smoke particles is a well-fitted, NIOSH-approved N95, because the seal, not the fabric, decides how much you breathe in.

Not well. When the problem is wildfire smoke, cloth and surgical masks are the wrong tool. Cloth face coverings should not be relied on for smoke, and one-strap or surgical masks are not built to seal to your face, so they offer only some protection when a proper mask is not available.1

A one-strap paper mask gives little or no protection from smoke particles.1 What decides how much a mask helps is the seal against your face, not the fabric. A well-fitted N95 or P100 cuts your exposure by at least tenfold; a loose mask barely helps. N95 masks are easily available and a P100 doesn't offer much additional protection, so use an N95 if you're going to be exposed to smoke outside. 12

Keep one limit in mind. Any mask filters particles, not the gases in smoke.2 A good mask cuts the biggest hazard, the fine particles, but it cannot scrub the air clean.

So don't count on a cloth or surgical mask on a smoky day. If you'll be out in it, wear a well-fitted N95, press it to a snug seal with no gaps, and still trim your time outside where you can.

Sources

  1. [1] U.S. EPA / USFS / CDC / CAPCOA / NPS / CARB. Wildfire Smoke: A Guide for Public Health Officials (Revised 2026). June 2026. Accessed August 6, 2026. https://www.epa.gov/system/files/documents/2026-06/wildfire-guide-for-public-health-officials-2026.pdf
  2. [2] NIOSH / CDC. How to Protect Workers and the Public from Wildfire Smoke (NIOSH Science Bulletin). January 2025. Accessed August 6, 2026. https://www.cdc.gov/niosh/bulletin/2025/wildfire-smoke.html

About the author

Dr. Colin Little

Dr. Colin Little

MD, FAWM, Chief Medical Officer, GOES Health

  • Board Certified Emergency Physician
  • Fellow of the Academy of Wilderness Medicine (FAWM)
  • Wilderness Medicine Fellowship, University of Utah
  • Emergency Medicine Residency and Chief Resident, Stanford / Kaiser
  • Doctor of Medicine, University of Arizona College of Medicine – Phoenix
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