COVID-19 is a respiratory illness caused by a novel coronavirus. The virus can be spread from person to person by respiratory droplets produced when an infected person coughs or sneezes, and by touching an object that is contaminated with the virus and then touching facial mucous membranes (mouth, nose, eyes). For more information about COVID-19, refer to the CDCs fact sheet, What You Need to Know About Coronavirus Disease 2019 (COVID-19).

During an infectious disease outbreak, health care workers are on the front lines and therefore at increased risk of being exposed to and contracting the disease. The Centers for Disease Control and Prevention (CDC) and the Occupational Safety and Health Administration (OSHA) require health care workers caring for patients with suspected or confirmed infectious disease to wear respiratory protection. The COVID-19 pandemic has led to an ongoing shortage of respiratory protection devices. This shortage has revealed two critical information needs: (1) understanding of the various types of respiratory protection devices and the varying degrees of protection they provide, and (2) accurate information about approved respiratory protection devices.

This guide is intended to condense the wealth of available information into a concise, easy-to-read document to help members make informed decisions about the selection of proper respiratory protection for the COVID-19 crisis as well as other potential hazards.

Types of protection: masks and respirators

For the purposes of this resource guide, definitions used in the Food and Drug Administration’s (FDA’s) Enforcement Policy for Face Masks and Respirators During the Coronavirus Disease (COVID-19) Public Health Policy will be used and are outlined in Table 1. More detailed descriptions and discussion follow.

Table 1. FDA definitions of face masks, filter facepiece respirators and surgical respirators

Mask or respirator type Definition and features
Face mask
  • A mask that covers the user’s nose and mouth.
  • May or may not meet fluid barrier or filtration efficiency levels.
Surgical mask
  • A mask that covers the user’s nose and mouth.
  • Provides a physical barrier to fluids and particulate materials.
  • The mask meets certain fluid barrier protection standards and Class I or Class II flammability tests.
Filtering facepiece respirator (FFR)
  • A disposable half-facepiece nonpowered air-purifying particulate respirator.
  • Intended for use to cover the nose and mouth of the wearer.
  • Helps reduce wearer exposure to pathogenic biological airborne particulates.
N95 respirator
  • A disposable half-mask FFR.
  • Covers the user’s airway (nose and mouth)
  • Offers protection from particulate materials at an N95 filtration efficiency level, per 42 CFR 84.181.
  • An N95 FFR used in a health care setting is a class II device regulated by the FDA under 21 CFR 878.4040 (FDA product code MSH).
NIOSH-approved N95 respirator
  • An N95 respirator
  • Approved by the National Institute for Occupational Safety and Health that meets filtration efficiency level per 42 CFR 84.181.
Surgical N95 respirator
  • A disposable FFR used in a health care setting.
  • Worn by health care providers during procedures to protect both the patient and the provider from the transfer of microorganisms, body fluids and particulate material at an N95 filtration efficiency level, per 42 CFR 84.181.
  • Surgical N95 Respirator is a class II device regulated by the FDA under 21 CFR 878.4040 (FDA product code MSH).

Respiratory protection for COVID-19

The CDC has outlined specific recommendations for personal protective equipment (gowns, gloves and respirators) for health care workers on the CDC Personal Protective Equipment Recommendations resource page. The CDC recommends that personnel caring for patients with suspected or confirmed coronavirus disease use an N95 filtering facepiece respirator (FFR) approved by the National Institute for Occupational Safety and Health (NIOSH) for use in health care settings. These respirators filter at least 95% of particles as small as 0.3 microns and are effective at filtering many types of other particles, including viruses and bacteria.

Because there are several face masks and respirators on the market, a review of the options and their protection and performance criteria is provided below.

Face masks

Face masks (sometimes called surgical masks or procedure masks) are loose fitting and therefore do not prevent leakage around the mouth upon inhalation; they provide only barrier protection against large respiratory droplets and particles and most do not effectively filter small particles from inhaled air. Face masks are worn by patients with suspected or confirmed COVID-19 to prevent contamination of the environment when the patient coughs or sneezes. Face masks are not approved by NIOSH.

Surgical masks

Surgical masks are loose fitting and therefore do not prevent leakage around the mouth upon inhalation. They are fluid resistant and provide protection against body fluid and other hazardous fluids, but do not provide reliable protection from small airborne particles. Because of this, surgical masks are not considered a form of respiratory protection. Surgical masks are worn during surgical procedures to protect the sterile field as well as the patient. Surgical masks are cleared as a medical device by the FDA.


A respirator is a personal protective device worn on the face or head that covers the nose and mouth. Particulate respirators filter out airborne particles and can be further categorized as:

  • Disposable: The entire respirator is discarded after use.
  • Reusable or elastomeric: The facepiece is cleaned or reused but the filter cartridge is discarded and replaced.
  • Powered air-purifying: The respirator has a battery-powered blower that moves air through filters.

NIOSH-approved N95 respirators

NIOSH-approved N95 respirators are tested and certified as meeting the standards established in 42 CFR 84. For detailed information on the standard, see the NIOSH Guide to the Selection and Use of Particulate Respirators.

There are 10 classifications of NIOSH-approved particulate FFRs, described in Table 2. Respirators are classified according to filtration percentage and oil resistance. It is important to understand the differences in the types of NIOSH-approved respirators for use in U.S. health care settings, as they provide different levels of protection based on performance and quality standards. N95 respirators must be fit tested annually, and repeated as necessary. For detailed information, see the CDC’s webpage on Healthcare Respiratory Program Resources: Fit Testing — NIOSH Documents.

Table 2. NIOSH-approved filtering facepiece respirator classifications

Filter class Description
N (Non-oil-resistant)
N95, N99, N100
Filter at least 95%, 99%, 99.97% of airborne particles as small as 0.3 microns.
R (Somewhat oil-resistant)
R95, R99, R100
Filter at least 95%, 99%, 99.97% of airborne particles.
P (Strongly resistant/oil-proof)
P95, P99, P100
Filter at least 95%, 99%, 99.97% of airborne particles.
HE (High-efficiency particulate air) Filters at least 99.97% of airborne particles. For use on powered air-purifying respirators only. PAPRs use only HE filters.

Surgical N95 respirators

Surgical N95 respirators (sometimes called medical respirators) are approved by NIOSH the FDA. They are recommended for health care professionals who require protection from airborne and fluid hazards when exposure to splashes or sprays of blood or other body fluid is a risk. According to the CDC, a surgical N95 respirator is not necessary for providers caring for patients with suspected or confirmed COVID-19 disease; a standard N95 respirator can be used.

How to identify NIOSH-approved respirators

According to the CDC and NIOSH, FFRs are required to have the following printed on the respirator itself:

  • Name of the approval holder or manufacturer, a registered trademark, an easily understood abbreviation of the approval holder’s or manufacturer’s name as recognized by NIOSH, or, if applicable, a private-label brand name.
  • NIOSH in block letters or the NIOSH logo
  • NIOSH testing and certification approval number (e.g., TC-84A-XXXX)
  • NIOSH filter series and filter efficiency level (e.g., N95, N99, N100, R95, P95, P99, P100)Model number or part number: The approval holder’s respirator model number or part number, represented by a series of numbers or alphanumeric markings (e.g., 8577 or 8577A)

NIOSH also recommends, but does not require, that the lot number and/or date of manufacture be included.

The figure below shows the markings used to identify approved NIOSH respirators.

Figure. NIOSH-approved respirator markings

Mask markings - exterior view

Source: Centers for Disease Control and Prevention.

The CDC offers several resources to help identify NIOSH-approved products. The CDC website provides a list of NIOSH-approved particulate FFRs.

For products not included on the approved NIOSH list noted above, the Certified Equipment List resource is available. To look up a NIOSH-approved disposable particulate respirator:

  • Access the Certified Equipment List.
  • In the “For Protections Against” section, select N95, N99, N100, R95, P95, or P100.
  • In the “Facepiece Type” section, select only Filtering Facepiece.
  • Click the View Results button.

If the product searched is not included in the results list, scroll through the list of private-label products. For additional assistance with the Certified Equipment List, see the instructions and tips page.

The CDC and NIOSH recommend that consumers always verify that respirators are listed on the approved NIOSH list. For more information, see the NIOSH publication Respiratory Awareness: Your Health May Depend on It.

Visit the COVID-19 Resources for more information.