Original Article | Published:

Evaluating the efficacy of cloth facemasks in reducing particulate matter exposure

Journal of Exposure Science and Environmental Epidemiology volume 27, pages 352357 (2017) | Download Citation

Abstract

Inexpensive cloth masks are widely used in developing countries to protect from particulate pollution albeit limited data on their efficacy exists. This study examined the efficiency of four types of masks (three types of cloth masks and one type of surgical mask) commonly worn in the developing world. Five monodispersed aerosol sphere size (30, 100, and 500 nm, and 1 and 2.5 μm) and diluted whole diesel exhaust was used to assess facemask performance. Among the three cloth mask types, a cloth mask with an exhaust valve performed best with filtration efficiency of 80–90% for the measured polystyrene latex (PSL) particle sizes. Two styles of commercially available fabric masks were the least effective with a filtration efficiency of 39–65% for PSL particles, and they performed better as the particle size increased. When the cloth masks were tested against lab-generated whole diesel particles, the filtration efficiency for three particle sizes (30, 100, and 500 nm) ranged from 15% to 57%. Standard N95 mask performance was used as a control to compare the results with cloth masks, and our results suggest that cloth masks are only marginally beneficial in protecting individuals from particles<2.5 μm. Compared with cloth masks, disposable surgical masks are more effective in reducing particulate exposure.

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Author information

Affiliations

  1. Department of Environmental Health Science, University of Massachusetts Amherst, Amherst, MA, USA

    • Kabindra M Shakya
    • , Alyssa Noyes
    • , Randa Kallin
    •  & Richard E Peltier

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Competing interests

The authors declare no conflict of interest.

Corresponding author

Correspondence to Richard E Peltier.

Supplementary information

About this article

Publication history

Received

Accepted

Published

DOI

https://doi.org/10.1038/jes.2016.42

Author contributions

REP, AN, and KMS contributed to the design, method, and data analysis. AN, RK, and KMS performed the experiments. All authors contributed to the article.

Supplementary Information accompanies the paper on the Journal of Exposure Science and Environmental Epidemiology website (http://www.nature.com/jes)

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