July 12, 2021

Rochelle P. Walensky, MD

Director

Centers for Disease Control and Prevention

1600 Clifton Rd., MS D-14

Atlanta, GA 30333

Dear Dr. Walensky:

On February 4, 2020, pursuant to Section 564(b)(1)(C) of the Act, the Secretary of the 

Department of Health and Human Services (HHS) determined that there is a public health 

emergency that has a significant potential to affect national security or the health and security of 

United States citizens living abroad, and that involves the virus that causes COVID-19. 

Pursuant to Section 564 of the Act, and on the basis of such determination, the Secretary of 

HHS then declared on March 2, 2020, that circumstances exist justifying the authorization of 

emergency use of personal respiratory protective devices during the COVID-19 outbreak, 

subject to the terms of any authorization issued under that section.1

On March 2, 2020, based on a request by the Centers for Disease Control and Prevention 

(CDC), the Food and Drug Administration (FDA) issued a letter authorizing emergency use of,

(1) all disposable filtering facepiece respirators (FFRs or respirators) approved by the National 

Institute for Occupational Safety and Health (NIOSH), in accordance with 42 CFR Part 84, as 

non-powered air-purifying particulate FFRs,

2 and (2) FFRs that were NIOSH-approved but 

have since passed the manufacturers’ recommended shelf-life, for use in healthcare settings by 

healthcare personnel (HCP)3 to prevent wearer exposure to pathogenic biological airborne 

1 U.S. Department of Health and Human Services, Determination of a Public Health Emergency and Declaration 

that Circumstances Exist Justifying Authorizations Pursuant to Section 564(b) of the Federal Food, Drug, and 

Cosmetic Act, 21 U.S.C. § 360bbb-3. 85 FR 7316 (February 7, 2020). U.S. Department of Health and Human 

Services, Declaration that Circumstances Exist Justifying Authorizations Pursuant to Section 564 of the Federal, 

Food, Drug, and Cosmetic Act, 21 U.S.C. § 360bbb-3. 85 FR 13907 (March 10, 2020) 2 To address the shortage caused by COVID-19, FDA issued the March 2, 2020 EUA, which permitted “authorized 

respirators” for distribution to healthcare personnel for use in healthcare settings, including respirators that were not 

devices prior to that use (e.g., they had been for industrial use). For more information, please see FDA’s March 11, 

2020 letter clarifying this aspect of the March 2, 2020 Letter of Authorization to CDC, available on FDA’s website 

at https://www.fda.gov/media/136023/download. 3 Healthcare personnel refers to all paid and unpaid persons serving in healthcare settings who have the potential for 

direct or indirect exposure to patients or infectious materials, including body substances (e.g., blood, tissue, and 

specific body fluids); contaminated medical supplies, devices, and equipment; contaminated environmental surfaces; 

or contaminated air. These healthcare personnel include, but are not limited to, emergency medical service 

personnel, nurses, nursing assistants, physicians, technicians, therapists, phlebotomists, pharmacists, dentists and 

dental hygienists, students and trainees, contractual staff not employed by the healthcare facility, and persons not 

directly involved in patient care, but who could be exposed to infectious agents that can be transmitted in the 
Page 2 – Dr. Walensky, Centers for Disease Control and Prevention

particulates during FFR shortages resulting from the Coronavirus Disease 2019 (COVID-19)

outbreak, pursuant to Section 564 of the Federal Food, Drug, and Cosmetic Act (the Act) (21 

U.S.C. §360bbb-3).

On March 27, 2020, in response to questions and concerns received by CDC and FDA since 

issuance of the March 2, 2020 letter, and requests to expand the scope to cover all particulatefiltering air purifying respirators (APRs), of which FFRs are a subset, and having concluded 

that revising the March 2, 2020 EUA is appropriate to protect the public health or safety under 

section 564(g)(2)(C) of the Act, FDA reissued the March 2, 2020, letter in its entirety with the 

amendments4 incorporated.

On March 28, 2020, to further address the shortage of disposable FFRs, FDA determined it was 

necessary to reissue the March 27, 2020 letter in order to amend the Scope of Authorization

(Section II) to additionally authorize the use of authorized respirators that have been

decontaminated pursuant to the terms and conditions of an FDA-authorized decontamination 

system.

5 Having concluded that revising the EUA is appropriate to protect the public health or 

safety under section 564(g)(2)(C) of the Act, FDA reissued the March 27, 2020 letter in its 

entirety with the amendment6 incorporated to authorize the emergency use of:

(1) Non-powered air-purifying particulate FFRs and reusable respirators such as 

elastomeric half and full facepiece respirators, approved by NIOSH in accordance 

with 42 CFR Part 84 and listed on the NIOSH Certified Equipment list (CEL) for 

non-powered air purifying respirators with particulate protection;

(2) Other powered air purifying respirators (PAPRs) approved by NIOSH, in 

accordance with 42 CFR Part 84, and that are listed on the NIOSH CEL for PAPRs 

with particulate protection;

(3) FFRs that were NIOSH-approved but have since passed the manufacturers’ 

recommended shelf-life, are not damaged, and have been held in accordance with 

manufacturers’ storage conditions in strategic stockpiles7 (referred to within this 

letter as “expired FFRs”); and,

(4) Any authorized respirator under (1) or (3) above that has been decontaminated 

pursuant to the terms and conditions of an authorized decontamination system,

healthcare setting (e.g., clerical, dietary, environmental services, laundry, security, engineering and facilities 

management, administrative, billing, and volunteer personnel). 4 The amendments to the March 2, 2020 letter revised: (1) the scope of the EUA; (2) the process by which 

manufacturers are added to the list of authorized respirators; (3) the process by which eligible respirators held 

beyond their shelf life are added to the list of authorized respirators, and; (4) add conditions of authorization for 

importers of authorized respirators.

5 In the March 28, 2020 letter, an “authorized decontamination system” meant any decontamination system for 

which FDA had issued an EUA. 6 The March 28, 2020, amendment to the March 27, 2020 letter revised the scope of authorized respirators to include 

any authorized respirators under (1) or (3) that are decontaminated using an authorized decontamination system. 7 For purposes of this authorization, strategic stockpiles refer to stockpiles of authorized respirators held by public 

health agencies that have legal responsibility and authority for responding to public health emergencies, based on 

political or geographical boundaries (e.g., city, county, tribal, territorial, State, or Federal), or functional range or 

sphere of authority (e.g., law enforcement, public health, military health) to prescribe, administer, deliver, distribute, 

hold, or dispense a medical product during an emergency situation.
Page 3 – Dr. Walensky, Centers for Disease Control and Prevention

for use in healthcare settings by HCP when used in accordance with CDC recommendations to 

prevent wearer exposure to pathogenic biological airborne particulates during respirator 

shortages resulting from the Coronavirus Disease 2019 (COVID-19) outbreak.

FDA has continued to evaluate the circumstances and appropriateness of this EUA and based 

on the totality of scientific evidence available, has determined that it is necessary to reissue this 

EUA to no longer authorize decontaminated or expired FFRs. This determination is based in 

part on new information about increased availability of NIOSH-approved FFRs for HCP use and 

CDC’s updated recommendations on returning to conventional capacity strategies. Of note, 

CDC no longer recommends that HCPs use decontaminated or non-NIOSH-approved FFRs, as 

well as respirators that are beyond the manufacturer-designated shelf life.

8 Based on this 

information, on April 9, 2021, May 27, 2021, and June 30, 2021, the FDA recommended that 

healthcare facilities transition away from crisis capacity conservation strategies (e.g., 

decontaminating disposable respirators, using non-NIOSH-approved respirators). Moreover, on 

June 30, 2021, the FDA revoked the remaining decontamination system and bioburden 

reduction EUAs. 

In conjunction with these actions, the FDA determined it is necessary to reissue the March 28, 

2020, letter in order to amend the Scope of Authorization (Section II) to remove FFRs that were 

NIOSH-approved but have since passed the manufacturers’ recommended shelf-life and to 

remove the emergency use authorization of decontaminated respirators from the scope of 

authorization. Therefore, this EUA now only authorizes the use of NIOSH-approved nonpowered air-purifying particulate FFRs and reusable respirators such as elastomeric half and full 

facepiece respirators, and other powered air purifying respirators (PAPRs), which can still be 

cleaned, disinfected, and reused per the manufacturer’s instructions as set forth in the revised 

Scope of Authorization (Section II). Having concluded that revising the EUA is appropriate to 

protect the public health or safety under section 564(g)(2)(C) of the Act, FDA is reissuing the 

March 28, 2020, letter in its entirety9 with the above described revisions. 

Having concluded that the criteria for issuance of this authorization under section 564(c) of the

Act are met, I am authorizing the emergency use of these respirators, as described in the Scope 

of Authorization (Section II) and pursuant to the Conditions of Authorization (Section IV) of 

this letter for use in healthcare settings by HCP when used in accordance with CDC 

recommendations to prevent wearer exposure to pathogenic biological airborne particulates 

during respirator shortages resulting from the COVID-19 outbreak. Respirators may be added 

to this EUA as provided for under Section II. For the most current CDC recommendations on

optimizing respirator use, please visit CDC’s webpage: Strategies for Optimizing the Supply of 

N95 Respirators. This EUA does not permit use of authorized respirators by the general public. 

I. Criteria for Issuance of Authorization

8 See CDC Strategies for Optimizing the Supply of N95 Respirators, available at 

https://www.cdc.gov/coronavirus/2019-ncov/hcp/respirators-strategy/index.html. 9 This letter issued on July 12, 2021, is being issued in its entirety, and was originally issued on March 2, 2020, and 

reissued on March 27, 2020 and March 28, 2020.
Page 4 – Dr. Walensky, Centers for Disease Control and Prevention

I have concluded that the emergency use of authorized respirators as described in the Scope of 

Authorization (section II) of this letter for use in healthcare settings by HCP to prevent wearer 

exposure to pathogenic biological airborne particulates during respirator shortages resulting 

from the COVID-19 outbreak meets the criteria for issuance of an authorization under Section

564(c) of the Act, because I have concluded that:

1. SARS-CoV-2, the virus that causes COVID-19, can cause a serious or life-threatening 

disease or condition, including severe respiratory illness, to humans infected by this 

virus;

2. Based on the totality of scientific evidence available to FDA, it is reasonable to believe 

that the authorized respirators may be effective in preventing HCP exposure to pathogenic 

biological airborne particulates during respirator shortages, and that the known and 

potential benefits of the authorized respirators, when used to prevent HCP exposure to 

such particulates during respirator shortages, outweigh the known and potential risks of 

such products; and

3. There is no adequate, approved, and available alternative to the emergency use of the 

respirators described for preventing HCP exposure to such particulates during respirator 

shortages to prevent disease spread.

10 Specifically, there are not sufficient quantities 

of FFRs that are both NIOSH-approved and meet FDA regulatory requirements to meet 

the needs of the U.S. healthcare system.11

II. Scope of Authorization

I have concluded, pursuant to Section 564(d)(1) of the Act, that the scope of this authorization is 

limited to the use of:

(1) Non-powered air-purifying particulate FFRs and reusable respirators such as 

elastomeric half and full facepiece respirators, approved by NIOSH in accordance 

with 42 CFR Part 84 and listed on the NIOSH Certified Equipment list (CEL) for 

non-powered air purifying respirators with particulate protection; and

(2) Other powered air purifying respirators (PAPRs) approved by NIOSH, in 

accordance with 42 CFR Part 84, and that are listed on the NIOSH CEL for PAPRs 

with particulate protection;

for use in healthcare settings by HCPs as recommended by CDC to prevent wearer exposure to 

pathogenic biological airborne particulates during respirator shortages resulting from the 

COVID-19 outbreak.

The Authorized Respirators

10 No other criteria of issuance have been prescribed by regulation under Section 564(c)(4) of the Act. 11 These respirators are an integral part of routine patient care. Providing HCP who are on the forefront of the 

COVID-19 response with FFRs consistent with the CDC’s guidance and recommendations is necessary in order to 

reduce the risk of illness in HCPs and increase their willingness to provide care to affected patients or those 

suspected of having COVID-19. 
Page 5 – Dr. Walensky, Centers for Disease Control and Prevention

As described in this section (Scope of Authorization (section II)) and pursuant to the Conditions 

of Authorization (section IV) of this letter, I am authorizing use of the following respirators:

(1) Non-powered air-purifying particulate FFRs and reusable respirators such as 

elastomerics half and full facepiece respirators approved by NIOSH in accordance 

with 42 CFR Part 84 and listed on the NIOSH CEL for non-powered air purifying 

respirators with particulate protection;

12 and

(2) Other powered air purifying respirators (PAPRs) approved by NIOSH, in accordance 

with 42 CFR Part 84, listed on the NIOSH CEL for PAPRs with particulate 

protection;

Manufacturers of NIOSH-approved FFRs that are listed on the NIOSH CEL for non-powered air 

purifying respirators with particulate protection will be notified of the inclusion of their models 

as authorized respirators under this EUA through FDA’s posting and public announcement of 

this reissued EUA at https://www.fda.gov/medical-devices/emergency-situations-medicaldevices/emergency-use-authorizations#covid19ppe. At any time, manufacturers may withdraw 

some or all of their authorized model numbers from this EUA by notifying FDA at CDRHNonDiagnosticEUA-Templates@fda.hhs.gov with a copy to CDC at RecordsRoom@cdc.gov.

FDA will list on its website those models that have been withdrawn or are otherwise no longer 

authorized under this EUA. Manufacturers and strategic stockpilers do not need to submit 

request to FDA to request authorization of additional NIOSH-approved respirators.

The above described authorized respirators listed in NIOSH CEL for non-powered air purifying 

respirators with particulate protection and the NIOSH CEL for PAPRs with particulate protection 

when labeled consistently with the labeling approved by NIOSH are authorized to be distributed 

to and used in healthcare settings by HCPs when used in accordance with CDC’s 

recommendations under this EUA, despite the fact that they do not meet certain requirements 

otherwise required by applicable federal law.

I have concluded, pursuant to Section 564(d)(2) of the Act, that it is reasonable to believe that 

the known and potential benefits of the authorized respirators when used consistent with the 

Scope of Authorization of this letter (Section II), outweigh the known and potential risks of such 

products.

I have concluded, pursuant to Section 564(d)(3) of the Act, based on the totality of scientific 

evidence available to FDA, that it is reasonable to believe that the authorized respirators may be 

12 In the March 2, 2020, request for an EUA, CDC provided FDA with a list of NIOSH-approved respirators (listed 

as Appendix A with the original March 2, 2020 EUA). All respirators from Appendix A referenced in the March 2, 

2020 Letter of Authorization that meet the criteria for issuance under section 564 of the Act and are also listed in the 

NIOSH CEL for non-powered air purifying respirators with particulate protection are automatically authorized for 

use under this reissued EUA. FDA notes, that respirators that are legally marketed under 21 CFR 878.4040 (surgical 

apparel) or 21 CFR 880.6260 (filtering facepiece respirator for use by the general public in public health medical 

emergencies) do not require an emergency use authorization (EUA). 

Moreover, because all NIOSH-approved FFRs that have been stockpiled in accordance with manufacturers’ storage 

conditions are automatically authorized under this reissued EUA, FDA is no longer requiring strategic stockpilers to 

send FDA information about their stockpiled product so long as their product meets the terms and conditions of this 

EUA.
Page 6 – Dr. Walensky, Centers for Disease Control and Prevention

effective at preventing HCP exposure to certain particulates to prevent disease spread, when used 

consistent with the Scope of Authorization of this letter (Section II), pursuant to Section

564(c)(2)(A) of the Act. 

FDA has reviewed the scientific information available to FDA, including the information 

supporting the conclusions described in Section I above, and conclude that the authorized

respirators, when used in healthcare settings to prevent HCP exposure to certain particulates to 

prevent disease spread (as described in the Scope of Authorization of this letter (Section II)), 

meet the criteria set forth in Section 564(c) of the Act concerning safety and potential

effectiveness.

The emergency use of the authorized respirators under this EUA must be consistent with, and 

may not exceed, the terms of this letter, including the Scope of Authorization (Section II) and the 

Conditions of Authorization (Section IV). Subject to the terms of this EUA and under the 

circumstances set forth in the Secretary of HHS's determination under Section 564(b)(1)(C) of 

the Act described above and the Secretary of HHS’s corresponding declaration under Section

564(b)(1) of the Act, the authorized respirators are authorized to be used in healthcare settings by 

HCPs under the terms and conditions of this EUA.

III. Waiver of Certain FDA Requirements

I am waiving applicable current good manufacturing practice requirements, including the quality

system requirements under 21 CFR Part 820 with respect to the design, manufacture, packaging, 

labeling, storage, and distribution of the authorized respirators that are used in accordance with 

this EUA. This waiver does not waive any applicable NIOSH requirements.

IV. Conditions of Authorization

Pursuant to Section 564(e) of the Act, I am establishing the following conditions on this 

authorization:

Centers for Disease Control and Prevention (CDC)

A. CDC will make available on its website and through other appropriate means, to

respirator manufacturers and HCPs, CDC’s recommendations to HCPs regarding use 

of NIOSH-approved APRs.

13

B. CDC will inform relevant stakeholders, such as manufacturers and HCPs, of this EUA, 

including the terms and conditions herein and any updates.

13 CDC’s webpage: Strategies for Optimizing the Supply of N95 Respirators. As of March 2, 2020, CDC also 

recommended on its Frequently Asked Questions about Personal Protective Equipment Page that if at all possible, 

respirators with exhalation valves should not be used in situations where a sterile field must be maintained (e.g., 

during an invasive procedure in an operating or procedure room) because the exhalation valve allows unfiltered 

exhaled air to escape into the sterile field.
Page 7 – Dr. Walensky, Centers for Disease Control and Prevention

C. CDC will provide to FDA any updates related to the NIOSH-approved APRs

manufacturers, contact information for each manufacturer, and model numbers. 

D. CDC will ensure that any records associated with this EUA are maintained until 

otherwise notified by FDA. Such records will be made available to FDA for inspection 

upon request. 

E. CDC may request changes to this EUA. Any request for changes to this EUA should be 

submitted to the Office of Strategic Partnerships and Technology Innovation 

(OST)/Center for Devices and Radiological Health (CDRH) and Office of Health 

Technology 4 (OHT4)/Division of Infection Control and Plastic and Reconstructive 

Surgery/CDRH. Such changes require appropriate authorization from FDA prior to 

implementation.

14

Manufacturers of Authorized Respirators

F. Manufacturers of authorized respirators must have a process in place and adequate 

Medical Device Reporting procedures, in accordance with 21 CFR 803, to report to FDA 

adverse events of which they become aware related to authorized respirators. 

Manufacturers must also establish a process to collect adverse event information from 

healthcare facility customers.

G. All descriptive printed matter, advertising, and promotional materials relating to the use 

of the authorized respirator under this authorization shall be consistent with the 

authorized labeling, as well as the terms set forth in this EUA, and meet the applicable 

requirements set forth in section 502(a) and (q)(1) and (r) of the Act, as applicable, and 

FDA implementing regulations.

H. No descriptive printed matter relating to the use of the authorized respirators may 

represent or suggest that the product is safe or effective for the prevention of COVID-19. 

I. Manufacturers of authorized respirators must ensure that any records associated with this 

EUA are maintained until otherwise notified by FDA. Such records must be made

available to FDA for inspection upon request.

Strategic Stockpilers

J. To the extent feasible given the emergency circumstances, strategic stockpilers will 

maintain reports of adverse events they receive from HCPs and facilities to which the 

14 The following types of revisions may be authorized without reissuing this letter: (1) non-substantive editorial

corrections to this letter; (2) new types of authorized labeling, including new fact sheets; (3) new carton/container

labels; (4) changes to manufacturing processes, including tests or other authorized components of manufacturing; (5)

new conditions of authorization to require data collection or study; (6) new instruments, associated software,

components or materials in the authorized product or modifications in the way that the device is used. All changes to

the authorization require review and concurrence from OST/CDRH and OHT4/OPEQ/CDRH. For changes of the 

type listed in (5) or (6), review and concurrence also is required from the Office of Counterterrorism and Emerging 

Threats/Office of the Chief Scientist.
Page 8 – Dr. Walensky, Centers for Disease Control and Prevention

authorized respirators are distributed.

K. Any such adverse events that the strategic stockpiler becomes aware will be reported to 

FDA via Medwatch Forms for FDA Safety Reporting. 

L. Strategic stockpilers of authorized respirators will ensure that any records associated 

with this EUA are maintained until otherwise notified by FDA. Such records will be 

made available to FDA for inspection upon request.

Importers

M. All descriptive printed matter, advertising, and promotional materials relating to the use 

of the authorized respirator under this authorization shall be consistent with the 

authorized labeling, as well as the terms set forth in this EUA, and meet the applicable 

requirements set forth in section 502(a) and (q)(1) and (r) of the Act, as applicable, and 

FDA implementing regulations.

N. No descriptive printed material relating to the use of the authorized respirators may 

represent or suggest that the product is safe or effective for the prevention of COVID-19.

O. Importers of authorized respirators must notify manufacturers of the terms and conditions 

of this EUA and ensure that the end user facility (e.g., each hospital, etc.) that receives 

the authorized respirators also receives the information required under Condition B. 

P. Importers of authorized respirators must ensure that any records associated with this 

EUA are maintained until the end of this public health emergency.

The emergency use of the authorized respirators as described in this letter of authorization must 

comply with the conditions and all other terms of this authorization. 

V. Duration of Authorization

This EUA will be effective until the declaration that circumstances exist justifying the 

authorization of the emergency use of personal respiratory protective devices during the 

COVID-19 outbreak is terminated under Section 564(b)(2) of the Act or the EUA is revoked 

under Section 564(g)(2) of the Act.

Sincerely,

____________________________

RADM Denise M. Hinton

Chief Scientist

Food and Drug Administration