March 24, 2022

New COVID-19 Resource Focuses on Preventing Inhalation of SARS-CoV-2

A new document published by the National Institute of Environmental Health Sciences (NIEHS) Worker Training Program outlines measures that can protect workers from inhaling the virus SARS-CoV-2, which causes COVID-19. The document emphasizes that SARS-CoV-2 is transmitted by exposure to infectious respiratory fluids, including inhalation of very fine respiratory droplets and aerosol particles that contain infectious virus, and that the smallest of these particles can remain suspended in the air for minutes to hours. According to NIEHS, factors such as the amount of time spent working near other people in enclosed spaces and the number of people working in these spaces may affect workers’ risk of inhaling SARS-CoV-2. The document highlights the effectiveness of ventilation systems as another factor that can influence workers’ level of risk. A brief discussion of the use of respiratory protection in the workplace is intended to help readers understand the differences between respirators, medical face masks, and barrier face coverings.

A table included in the document provides a framework for the selection of respiratory protection based on job task; risk category, which has to do with whether a worker has close contact with others; and community transmission. The table also refers users to relevant resources from CDC and NIOSH as well as applicable OSHA and ASTM standards.

The NIEHS document stresses that a combination of precautions is necessary to protect workers from exposure to SARS-CoV-2. Additional measures recommended within the document include ensuring that staff are fully vaccinated or regularly rested for infection, limiting interactions between staff where possible, and implementing ventilation and filtration improvements or using portable air cleaners as needed.

View all of NIEHS’ recommendations in its new COVID-19 brief (PDF).

Related: A fact sheet published last year by the NIEHS Worker Training Program outlines guidance on the selection and use of portable air cleaners to protect workers from exposure to SARS-CoV-2.