New OSHA Guidance Debunks Fears About Wearing Masks

By Anne Cullen
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Law360 (July 31, 2020, 2:04 PM EDT) -- Masks worn to stymie the spread of coronavirus won't hinder the wearer's oxygen levels or cause a harmful buildup of carbon dioxide, the Occupational Safety and Health Administration made clear in new guidance Friday.  

In the latest update to its running list of coronavirus guidance, the agency said medical masks and cloth face coverings don't interfere with a wearer's oxygen or carbon dioxide levels in any significant way, as they're designed to be breathed through and not sealed tight enough to trap enough carbon dioxide to be harmful.

OSHA updated its coronavirus guidance Friday to address concerns about the safety of wearing masks. (AP Photo/Mark Lennihan)

"Most carbon dioxide particles will either go through the mask or escape along the mask's loose-fitting perimeter," it said. "Some carbon dioxide might collect between the mask and the wearer's face, but not at unsafe levels."

OSHA also pushed back on claims that some of its own rules on respiratory safety and protection from air contaminants on the job may get in the way of workplace mask mandates.

A Facebook post that went viral earlier this summer alleged that wearing a mask at work contravenes OSHA's Respiratory Protection Standard — which requires employers to keep oxygen levels at certain levels — by suppressing the wearer's oxygen intake, resulting in headaches, high blood pressure and possibly brain damage.

However, the agency said this standard and others used to back up similar conspiracy theories don't pertain to a traditional workplace.

"These standards do not apply to the wearing of medical masks or cloth face coverings in work settings with normal ambient air," OSHA said. "These standards would only apply to work settings where there are known or suspected sources of chemicals (e.g., manufacturing facilities) or workers are required to enter a potentially dangerous location (e.g., a large tank or vessel)."

Masks and cloth face coverings are an effective way to curb infections, OSHA added.

"Cloth face coverings and medical masks can help prevent the spread of potentially infectious respiratory droplets from the wearer to their co-workers, including when the wearer has COVID-19 and does not know it," the agency said.

The agency recommended that employees wear masks in guidance updates revealed earlier this month, advising that "employers may choose to ensure that cloth face coverings are worn" in order to protect workers.

While masks remain a polarizing issue in the U.S. — based on alleged health concerns as well as the authority of local governments to mandate their use — studies of hospital systems and retail environments have shown they can reduce transmission of the coronavirus.

The Centers for Disease Control and Prevention has touted them as one of the most powerful tools in our arsenal for combating the disease.

-- Additional reporting by Jon Steingart. Editing by Abbie Sarfo.

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