Quantitative headform fit evaluation and predictive modeling to assist with selecting N95 filtering facepiece respirators to mitigate respiratory hazards

Proper respirator fit is essential for ensuring that NIOSH Approved® N95® filtering facepiece respirators (FFRs) provide their expected level of respiratory protection. Because respirator fit varies according to both respirator design and an individual's facial dimensions, selecting a well-fitting respirator can be difficult, particularly in settings where formal respirator fit testing is unavailable or resources are limited. To better understand these relationships, the National Institute for Occupational Safety and Health (NIOSH) conducted a laboratory study evaluating the fit performance of 12 NIOSH Approved N95 FFR models distributed through the U.S. Strategic National Stockpile (SNS). Quantitative fit evaluations were performed using five ISO Static Advanced Headforms, which represent approximately 95% of the U.S. worker population based on NIOSH’s 2003 Anthropometric Survey, resulting in 540 individual headform fit tests. These experimental data were subsequently combined with anthropometric data from the 2003 NIOSH survey to develop and evaluate predictive models that estimate an individual's representative headform size from a limited set of facial measurements. The datasets were collected to improve understanding of how respirator fit varies across representative facial sizes and to support development of tools that may assist workers, employers, emergency response organizations, researchers, and the public in identifying respirator models that are more likely to provide an adequate fit. The quantitative fit evaluation data were used to characterize fit performance across multiple respirator models and headform sizes, while the anthropometric modeling data were used to develop and evaluate multinomial logistic regression models capable of predicting headform size with high accuracy under laboratory conditions. Because the fit evaluation was conducted using laboratory manikin headforms rather than human subjects, the findings should not be interpreted as a replacement for OSHA-accepted respirator fit testing. Additionally, only selected NIOSH Approved N95 FFR models available through the SNS at the time of the study were evaluated, and further validation with human subjects is needed before predictive modeling approaches are applied in real-world respirator selection. Nevertheless, these datasets provide a valuable resource for research involving respirator fit, facial anthropometry, respirator design, and development of future respirator selection and fit assessment tools.

[
  "009:20"
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{
  "fn": "Research Branch (RB) National Personal Protective Technology Laboratory (NPPTL)",
  "@type": "vcard:Contact",
  "hasEmail": "mailto:PPEConcerns@cdc.gov"
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    "downloadURL": "https://data.cdc.gov/download/inau-mhw3/application/x-zip-compressed"
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[
  "workplace"
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  "009:034"
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  "name": "Centers for Disease Control and Prevention",
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[
  "National Institute for Occupational Safety and Health"
]