Question: Does wearing a medical/surgical mask or cloth face covering cause unsafe oxygen levels or harmful carbon dioxide levels to the wearer?

Answer:

No. Medical masks, including surgical masks, are routinely worn by healthcare workers throughout the day as part of their personal protective equipment (PPE) ensembles and do not compromise their oxygen levels or cause carbon dioxide buildup. They are designed to be breathed through and can protect against respiratory droplets, which are typically much larger than tiny carbon dioxide particles. Consequently, most carbon dioxide particles will either go through the mask or escape along the mask's loose-fitting perimeter. Some carbon dioxide might collect between the mask and the wearer's face, but not at unsafe levels.

Like medical masks, cloth face coverings are loose-fitting with no seal and are designed to be breathed through. In addition, workers may easily remove their medical masks or cloth face coverings periodically (and when not in close proximity with others) to eliminate any negligible build-up of carbon dioxide that might occur. 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.

Some people have mistakenly claimed that OSHA standards (e.g., the Respiratory Protection standard, 29 CFR 1910.134; the Permit-Required Confined Space standard 29 CFR 1910.146; and the Air Contaminants standard, 29 CFR 1910.1000) apply to the issue of oxygen or carbon dioxide levels resulting from the use of medical masks or cloth face coverings in work settings with normal ambient air (e.g. healthcare settings, offices, retail settings, construction). These standards do not apply to the wearing of medical masks or cloth face coverings in work settings with normal ambient air). 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).

Question: Are surgical masks or cloth face coverings acceptable respiratory protection in the construction industry, when respirators would be needed but are not available because of the COVID-19 pandemic?

Answer:

No. Employers must not use surgical masks or cloth face coverings when respirators are needed.

In general, employers should always rely on a hierarchy of controls that first includes efforts to eliminate or substitute out workplace hazards and then uses engineering controls (e.g., ventilation, wet methods), administrative controls (e.g., written procedures, modification of task duration), and safe work practices to prevent worker exposures to respiratory hazards, before relying on personal protective equipment, such as respirators. When respirators are needed, OSHA's guidance describes enforcement discretion around use of respirators, including in situations in which it may be necessary to extend the use of or reuse certain respirators, use respirators beyond their manufacturer's recommended shelf life, and/or use respirators certified under the standards of other countries or jurisdictions.

The Centers for Disease Control and Prevention and OSHA have described crisis strategies intended for use in healthcare in which surgical masks or cloth face coverings may offer more protection than no mask at all when respirators are needed but are not available. Such information is not intended to suggest that surgical masks or cloth face coverings provide adequate protection against exposure to airborne contaminants for which respirators would ordinarily be needed. Although OSHA's enforcement guidance describes equipment prioritization that includes surgical masks, employers must still comply with the provisions of any standards that apply to the types of exposures their workers may face. For example, the permissible exposure limits of all substance-specific standards, such as asbestos and silica, remain in place, and surgical masks are not an acceptable means of protection when respirators would otherwise be required (e.g., when engineering, administrative, and work practice controls do not sufficiently control exposures).

If respirators are needed but not available (including as described in the OSHA enforcement guidance noted above), and hazards cannot otherwise be adequately controlled through other elements of the hierarchy of controls (i.e., elimination, substitution, engineering controls, administrative controls, and/or safe work practices), avoid worker exposure to the hazard. Whenever a hazard presents an imminent danger, and in additional situations whenever feasible, the task should be delayed until feasible control measures are available to prevent exposures or reduce them to acceptable levels (i.e., at or below applicable OSHA permissible exposure limits).

Question: If I wear a reusable cloth face covering, how should I keep it clean?

Answer:

CDC provides guidance on washing face coverings. OSHA suggests following those recommendations, and always washing or discarding cloth face coverings that are visibly soiled.

Question: If workers wear cloth face coverings, do employers still need to ensure social distancing measures in the workplace?

Answer:

Yes. Cloth face coverings are not a substitute for social distancing measures.

Question: Should workers wear a cloth face covering while at work, in accordance with the Centers for Disease Control and Prevention recommendation for all people to do so when in public?

Answer:

OSHA generally recommends that employers encourage workers to wear face coverings at work. Face coverings are intended to prevent wearers who have Coronavirus Disease 2019 (COVID-19) without knowing it (i.e., those who are asymptomatic or pre-symptomatic) from spreading potentially infectious respiratory droplets to others. This is known as source control.

Consistent with the Centers for Disease Control and Prevention (CDC) recommendation for all people to wear cloth face coverings when in public and around other people, wearing cloth face coverings, if appropriate for the work environment and job tasks, conserves other types of personal protective equipment (PPE), such as surgical masks, for healthcare settings where such equipment is needed most.

Employers have the discretion to determine whether to allow employees to wear cloth face coverings in the workplace based on the specific circumstances present at the work site. For some workers, employers may determine that wearing cloth face coverings presents or exacerbates a hazard. For example, cloth face coverings could become contaminated with chemicals used in the work environment, causing workers to inhale the chemicals that collect on the face covering. Over the duration of a work shift, cloth face coverings might also become damp (from workers breathing) or collect infectious material from the work environment (e.g., droplets of other peoples' infectious respiratory secretions). Workers may also need to use PPE that is incompatible with the use of a cloth face covering (e.g., an N95 filtering facepiece respirator).

Where cloth face coverings are not appropriate in the work environment or during certain job tasks (e.g., because they could become contaminated or exacerbate heat illness), employers can provide PPE, such as face shields and/or surgical masks, instead of encouraging workers to wear cloth face coverings. Like cloth face coverings, surgical masks and face shields can help contain the wearer's potentially infectious respiratory droplets and can help limit spread of COVID-19 to others.

Note that cloth face coverings are not considered PPE and cannot be used in place of respirators when respirators are otherwise required.

Learn more about cloth face coverings on the CDC website.

Employers should consider evaluating their accessible communication policies and procedures to factor in potentially providing masks with clear windows to facilitate interaction between employees and members of the public who need to lip-read to communicate.

Question: Are employers required to provide cloth face coverings to workers?

Answer:

Cloth face coverings are not considered personal protective equipment (PPE) and are not intended to be used when workers need PPE for protection against exposure to occupational hazards. As such, OSHA's PPE standards do not require employers to provide them.

• The General Duty Clause, Section 5(a)(1) of the Occupational Safety and Health Act, requires each employer to furnish to each of his employees employment and a place of employment which are free from recognized hazards that are causing or are likely to cause death or serious physical harm. Control measures may include a combination of engineering and administrative controls, safe work practices like social distancing, and PPE.
• However, employers may choose to ensure that cloth face coverings are worn as a feasible means of abatement in a control plan designed to address hazards from SARS-CoV-2, the virus that causes COVID-19. Employers may choose to use cloth face coverings as a means of source control, such as because of transmission risk that cannot be controlled through engineering or administrative controls, including social distancing.

Question: What are the key differences between cloth face coverings, surgical masks, and respirators?

Answer:

Cloth face coverings:

• May be commercially produced or improvised (i.e., homemade) garments, scarves, bandanas, or items made from t-shirts or other fabrics.
• Are worn in public over the nose and mouth to contain the wearer's potentially infectious respiratory droplets produced when an infected person coughs, sneezes, or talks and to limit the spread of SARS-CoV-2, the virus that causes Coronavirus Disease 2019 (COVID-19), to others.
• Are not considered personal protective equipment (PPE).
• Will not protect the wearer against airborne transmissible infectious agents due to loose fit and lack of seal or inadequate filtration.
• Are not appropriate substitutes for PPE such as respirators (e.g., N95 respirators) or medical face masks (e.g., surgical masks) in workplaces where respirators or face masks are recommended or required to protect the wearer.
• May be used by almost any worker, although those who have trouble breathing or are otherwise unable to put on or remove a mask without assistance should not wear one.
• May be disposable or reusable after proper washing.

Surgical masks:

• Are typically cleared by the U.S. Food and Drug Administration as medical devices (though not all devices that look like surgical masks are actually medical-grade, cleared devices).
• Are used to protect workers against splashes and sprays (i.e., droplets) containing potentially infectious materials. In this capacity, surgical masks are considered PPE. Under OSHA's PPE standard (29 CFR 1910.132), employers must provide any necessary PPE at no-cost to workers.¹
• May also be worn to contain the wearer's respiratory droplets (e.g., healthcare workers, such as surgeons, wear them to avoid contaminating surgical sites, and dentists and dental hygienists wear them to protect patients).
• Should be placed on sick individuals to prevent the transmission of respiratory infections that spread by large droplets.
• Will not protect the wearer against airborne transmissible infectious agents due to loose fit and lack of seal or inadequate filtration.
• May be used by almost anyone.
• Should be properly disposed of after use.

Respirators (e.g., filtering facepieces):

• Are used to prevent workers from inhaling small particles, including airborne transmissible or aerosolized infectious agents.
• Must be provided and used in accordance with OSHA's Respiratory Protection standard (29 CFR 1910.134).
  • Must be certified by the National Institute for Occupational Safety and Health (NIOSH).
    • OSHA has temporarily exercised its enforcement discretion concerning supply shortages of disposable filtering facepiece respirators (FFRs), including as it relates to their extended use or reuse, use beyond their manufacturer's recommended shelf life, use of equipment from certain other countries and jurisdictions, and decontamination.
  • Need proper filter material (e.g., N95 or better) and, other than for loose-fitting powered, air purifying respirators (PAPRs), tight fit (to prevent air leaks).
  • Require proper training, fit testing, availability of appropriate medical evaluations and monitoring, cleaning, and oversight by a knowledgeable staff member.
    • OSHA has temporarily exercised its enforcement discretion concerning annual fit testing requirements in the Respiratory Protection standard (29 CFR 1910.134), as long as employers have made good-faith efforts to comply with the requirements of the standard and to follow the steps outlined in the March 14, 2020, and April 8, 2020, memoranda (as applicable to their industry).
  • When necessary to protect workers, require a respiratory protection program that is compliant with OSHA's Respiratory Protection standard (29 CFR 1910.134). OSHA consultation staff can assist with understanding respiratory protection requirements.
  • FFRs may be used voluntarily, if permitted by the employer. If an employer permits voluntary use of FFRs, employees must receive the information contained in Appendix D of OSHA's Respiratory Protection standard (29 CFR 1910.134).

¹ If surgical masks are being used only as source control—not to protect workers against splashes and sprays (i.e., droplets) containing potentially infectious materials—OSHA's PPE standards do not require employers to provide them to workers. However, the General Duty Clause, Section 5(a)(1) of the Occupational Safety and Health Act, requires each employer to furnish to each of his employees employment and a place of employment which are free from recognized hazards that are causing or are likely to cause death or serious physical harm. Control measures may include a combination of engineering and administrative controls, including safe work practices like social distancing. Choosing to ensure use of surgical masks for source control may constitute a feasible means of abatement as part of a control plan designed to address hazards from SARS-CoV-2, the virus that causes COVID-19. Back to Text

Question: Is OSHA providing any guidance for companies performing remediation and clean-up efforts in high-risk situations, such as disassembly or cleanup of triage or temporary hospitals?

Answer:

OSHA's COVID-19 Safety and Health Topics page provides information for workers performing environmental cleaning and disinfection activities, including in healthcare settings and generally.

The Centers for Disease Control and Prevention also provides information on environmental infection control related to cleaning and disinfecting healthcare facilities.

Companies providing specialized remediation or clean-up services need to have expertise in industrial hygiene and environmental remediation.

Question: How should I clean and disinfect my workplace?

Answer:

The Centers for Disease Control and Prevention provides updated information about cleaning and disinfecting public spaces, workplaces, businesses, schools, and homes.

Question: Where can employers find general information about, and requirements for, protecting workers during the COVID-19 pandemic?

Answer:

OSHA's COVID-19 Safety and Health Topics page provides the most recent guidance to help employers protect their workers and comply with OSHA requirements during the COVID-19 pandemic. Resources include:

• Guidance on Preparing Workplaces for COVID-19 (Spanish)
• Worker Exposure Risk to COVID-19 (Spanish)
• Alert: Prevent Worker Exposure to Coronavirus (COVID-19) (Spanish)
• Alert: COVID-19 Guidance for Retail Workers (Spanish)
• List of relevant OSHA standards for COVID-19
• Temporary enforcement guidance in effect during the COVID-19 pandemic

The Centers for Disease Control and Prevention (CDC) also provides information for businesses, workplaces, and workers, including health and safety steps for specific occupations.