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In light of the current situation regarding the COVID-19 pandemic and the shortage of respiratory protection in the health care industry, we have received many questions regarding the use of radiation (e.g., ultraviolet, x-ray, or gamma) to sterilize certain respirators (e.g., N95 respirators). The Health Physics Society can speak to the safety of the use of radiation; however, we cannot speak to the effectiveness of radiation for the purpose of sterilization of respirators for reuse during the COVID-19 crisis. Disinfection of such equipment involves both biological considerations (e.g., radiation dose required to eradicate the virus) and considerations about the effects of treatment on the equipment itself. Other organizations, such as the N95DECON consortium, have evaluated the effectiveness of irradiation against other similar viruses, and you may want to review their information.

A comprehensive review of the Centers for Disease Control and Prevention (CDC) recommendations concerning reuse and disinfection of face masks can be found on the COVID-19 pages of the CDC's website. The CDC concludes that filtering facepiece respirator (FFR) "decontamination and reuse may need to be considered as a crisis capacity strategy to ensure continued availability. Based on the limited research available, ultraviolet germicidal irradiation, vaporous hydrogen peroxide, and moist heat showed the most promise as potential methods to decontaminate FFRs."

You may also want to review the 3M technical bulletin on disinfection methods.

This information will be updated as needed based on revised and/or additional information as it is received.


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