The trusted source for
healthcare information and
Got N-95s? CDC guidance if you are running short
Surgical mask better than nothing
The Centers for Disease Control and Prevention (CDC) in Atlanta has issued new guidance on the selection and handling of respirators for severe acute respiratory syndrome (SARS), including recommendations to follow when respirators are either not available or in short supply. Key aspects are summarized as follows:
The transmission of SARS appears to occur predominantly by direct contact with infectious material, including dispersal of large respiratory droplets.
However, it also is possible that SARS can be spread through the airborne route. Accordingly, the CDC has recommended the use of N-95 respirators, consistent with respiratory protection for airborne diseases, such as tuberculosis. SARS, unlike tuberculosis, also appears to spread by direct contact with respiratory secretions, which makes touching contaminated objects a potential concern. Although re-aerosolization of infectious material is unlikely under normal use conditions, infectious material deposited on a respirator may cause it to become a vehicle for direct or indirect transmission. Therefore, additional infection control measures applicable to this specific situation are needed.
1. A National Institute for Occupational Safety and Health-certified, disposable N-95 respirator is sufficient for routine airborne isolation precautions. Use of a higher level of respiratory protection may be considered for certain aerosol-generating procedures.
A. Respirators should be used in the context of a complete respiratory protection program in accordance with Occupational Safety and Health Administration regulations. This includes training and fit-testing to ensure a proper seal between the respirator’s sealing surface and the wearer’s face. For detailed information on respirator programs including fit-test procedures, go to: www.osha.gov/SLTC/etools/respiratory.
B. Once worn in the presence of a SARS patient, the respirator should be considered potentially contaminated with infectious material, and touching the outside of the device should be avoided. Upon leaving the patient’s room, the disposable respirator should be removed and discarded, followed by hand hygiene.
2. If a sufficient supply of respirators is not available, health care facilities may consider reuse as long as the device has not been obviously soiled or damaged (e.g., creased or torn). Data on reuse of respirators for SARS are not available. Reuse may increase the potential for contamination; however, this risk must be balanced against the need to fully provide respiratory protection for health care personnel. If N-95 respirators are reused for contact with SARS patients, implement a procedure for safer reuse to prevent contamination through contact with infectious droplets on the outside of the respirator.
A. Consider wearing a loose-fitting barrier that does not interfere with fit or seal (e.g., surgical mask, face shield) over the respirator.
B. Remove the barrier upon leaving the patient’s room and perform hand hygiene. Surgical masks should be discarded; face shields should be cleaned and disinfected.
C. Remove the respirator and either hang it in a designated area or place it in a bag. (Consider labeling respirators with a user’s name before use to prevent reuse by another individual.)
D. Use care when placing a used respirator on the face to ensure proper fit for respiratory protection and to avoid contact with infectious material that may be present on the outside of the mask.
E. Perform hand hygiene after replacing the respirator on the face.
3. When rubber or powered air-purifying respirators (PAPRs) are used, their reusable elements should be cleaned and disinfected after use, in accordance with manufacturer’s recommendations. When half- or full-face-piece rubber negative-pressure respirators are used by more than one individual, filters should be replaced between individual users. When PAPRs are used, the filters should be replaced following manufacturer’s recommendations. All used filters must be discarded safely.
4. Respiratory protective devices with a filter efficiency of 95% or greater (e.g., N-95, N-99, N-100) may not be available in some settings due to supply shortages or other factors. In this situation, a surgical (procedure) mask should be worn. Surgical masks will provide barrier protection against large droplets that are considered to be the primary route of SARS transmission. How-ever, surgical masks may not adequately protect against aerosol or airborne particles, primarily because they allow for leakage around the mask and cannot be fit-tested. The mask should resist fluid penetration and fit tightly around the mouth and nose when properly applied to the face.