FDA issues guidance on use of dry heat to support reuse of certain respirators

Today, the U.S. Food and Drug Administration (FDA) issued guidance on the use of dry heat to help support the single-user reuse of certain particulate filtering facepiece respirators (FFRs), such as N95 respirators, by health care personnel when there is a limited supply of respirators during the COVID-19 public health emergency.

The immediately-in-effect guidance provides the FDA's thinking and recommendations regarding the use of bioburden reduction systems that use dry heat to reduce the bioburden, or amount of microorganisms present, on certain respirators for reuse by a single user. Bioburden reduction systems are intended to achieve a certain level in microbial reduction on a device; these are not decontamination systems. Additionally, these systems should only be used in conjunction with existing Centers for Disease Control and Prevention (CDC) recommendations for FFR reuse.

There exists sufficient evidence demonstrating that there is a reduction of microbial load on certain respirators when exposed to certain dry heat parameters. Bioburden reduction systems can play an important role in the ongoing efforts to help address shortages of FFRs. Today's guidance is another example of how FDA is working to address critical shortages in personal protective equipment and help protect health care personnel during the COVID-19 public health emergency."

Dr. Binita Ashar, Director of the Division of Surgical Devices in FDA's Center for Devices and Radiological Health

Under this policy, the FDA does not intend to object to the use of certain dry heat systems for the purpose of reducing bioburden and supporting single-user reuse of otherwise disposable FFRs that are compatible with dry heat bioburden reduction systems without marketing authorization. Manufacturers should follow the system settings for bioburden reduction—such as temperature and time—and labeling recommended in this guidance, and also follow existing CDC reuse recommendations, such as storing the respirator in a breathable paper bag for a minimum of five days between each use and limiting the number of wears to no more than five per respirator.

The FDA has issued emergency use authorizations (EUAs) for certain decontamination systems for decontaminating compatible FFRs, and has issued guidance to provide recommendations for sponsors requesting EUAs for decontamination and bioburden reduction systems for surgical masks and respirators. However, today's guidance is the first enforcement policy guidance specifically for bioburden reduction systems for FFRs. To date, no EUAs have been issued for bioburden reduction systems that use dry heat. While dry heat bioburden reduction systems do not provide FFR decontamination, which is a higher level of microbial reduction, these systems may still be sufficient to reduce bioburden on compatible FFRs and support single-user reuse of these respirators by supplementing existing CDC reuse recommendations.

This policy applies to bioburden reduction of FFRs that do not have exhalation valves, do not incorporate a duck-bill design, and do not contain antimicrobial/antiviral agents and that 1) have been FDA-cleared, or 2) have been FDA-authorized under the EUA for CDC's National Institute for Occupational Safety and Health (NIOSH)-approved FFRs, or 3) have been FDA-authorized under the EUA for imported, non-NIOSH-approved FFRs that are not manufactured in China. The FDA is considering revising the scope of authorization of the above mentioned FFR EUAs to include bioburden reduction under certain circumstances. At this time, FFRs that have had bioburden reduction with one of these systems are not authorized under an existing EUA.

Currently, there are no FDA-cleared or approved devices for decontamination or bioburden reduction of respirators.