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COVID-19 and Face Masks for Providers: Frequently Asked Questions

(Version 2.0; last updated May 4, 2020)

Input from Dr. Steve Pergam

Note: Please review ASH's disclaimer regarding the use of the following information.

Should all health care workers who interact with patients routinely wear a mask given the shortage of PPE?

Since early April 2020, the CDC has recommended that the general population wear masks (defined as cloth face coverings) in public settings where other physical distancing measures (6 ft apart) are difficult to maintain (e.g., grocery stores, health care facilities, pharmacies). Such policies are strongly recommended in areas with significant community-based transmission.

Short of a future randomized trial examining the impact of routine mask usage on the rate of COVID19 infection, there is no definitive way to measure the effectiveness of mask usage in preventing spread of SARS-CoV-2. However, several lines of evidence support the routine use of masks by health-care workers including:

  • There is widespread community transmission of SARS-CoV-2, the virus that causes COVID-19, throughout the US.
  • While COVID-19 is predominantly spread by large respiratory droplets produced when a person coughs or sneezes, the virus may be spread by individuals who are asymptomatic or pre-symptomatic (those who have detectable virus prior to the development of symptoms); individuals with mild symptoms who may not be recognized to have COVID-19 may also play an important role.

Epidemiologic and modeling studies suggest asymptomatic/pre-symptomatic infection can play an important role in perpetuating community and nosocomial transmission.1-3
When considering required/extended-use masking policies centers should consider the following:

  • Screening anyone entering the facility for active symptoms. All symptomatic patients should be masked and placed in droplet/contact precautions. Patients presenting in acute respiratory failure who are expected to require airborne generating procedures (e.g. intubation) should be placed in airborne/contact precautions.
  • Institutions should consider masking all health care workers while in clinical facilities, particularly in patient care areas or where physical distancing is not possible (e.g. work rooms). However, local decisions regarding routine or extended-masking policies, particularly the type of mask used, must be based on available supply. Masks are not a substitute for physical distancing and hand washing.
  • Assure that patients with known or suspected COVID-19 infection or patients who have not been tested who are in droplet/contact precautions, are seen with a face shield in addition to a mask to protect the eyes and the mask from contamination.
  • Centers may also want to consider masking (with a procedure/surgical mask) all patients, caregivers/family and others that enter the facility. Ability to provide universal masking for all hospital visitors and staff is dependent on local supply.
  • Patients who are undergoing airborne generating procedures (e.g. bronchoaveolar lavage or intubation), should be cared for in a negative pressure room (if available), and under airborne/contact precautions (N-95 mask plus face shield or PAPR, gown, and gloves).
  • Required or extended-use masking policies necessitate staff education on how to properly use masks for extended periods. It is critical to assure training covers topics such as safe donning and doffing, appropriate use (covering nose and mouth), avoiding touching the front of the facemask during care, use during breaks and careful hand hygiene before and after mask removal, otherwise the risk of infection to the wearer may be higher than wearing no mask at all.
  • In addition, education for staff to avoid coming to work with sick/symptomatic remains a key point of emphasis, particularly when considering required or extended-use masking policies, as masking may lead to staff to come to work with mild symptoms.
  • The increased utilization of PPE in health care has made PPE more difficult to acquire, so routine masking can be used as a conservation strategy. Centers should have awareness of local PPE supply, and a system for monitoring shortages, that can take into account changes in use patterns.
  • Development of COVID-19 specific units to conserve PPE.
  • Strategies to improve the available mask supply include reuse or extended-use masks (“one mask per day”) should be considered. Methods for storage of undamaged masks, including storage in a paper (not plastic) bag when not in use must be considered.
  • Extending use of N95 filtering facepiece respirators (N95 FFRs) is an important PPE conservation strategy. N-95s may be decontaminated using a number of decontamination procedures, including ultraviolet germicidal irradiation (UVGI), heating at high levels or through use of aerosolized hydrogen peroxide.
  • Efforts should be made to dissuade the public from purchasing surgical masks and N-95 respirators that are needed for health care personnel in high-risk situations.
  • Because of the wide variety of materials used and construction techniques, no global statement can be made of about the ability of homemade or commercially produced (i.e. non-medical) masks to reduce the risk of COVID-19 to the wearer or others around them. However, barriers that reduced droplet spread and that reinforces precautions and prevents touching of the face may be helpful and can be considered in non-clinical/administrative areas.
  • Staff should be encouraged to wear homemade/cloth masks when not in the hospital/clinic, but in public spaces (e.g. grocery store), as per CDC recommendations.

For additional information, see:


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