COVID-19: Evaluation of Disinfection Options for N95 Filtering Facepiece Respirators in the Context of the Pandemic
This publication uses the term “disinfection” of single-use N95 filtering facepiece respirators (FFRs) (also called N95 masks) to refer to the chemical or physical process that inactivates infectious agents. It should be noted that the various reference publications and documents on the subject consulted by the Centre d’expertise en retraitement des dispositifs médicaux (CERDM) use the terms "decontamination," "disinfection," or both. The CERDM has chosen the term “disinfection” to conform to the reprocessing nomenclature that is generally accepted in Canada (CSA Z314.18). According to this nomenclature, the term decontamination is more general and includes the process of cleaning followed by the inactivation of infectious agents. However, in the context of reprocessing of N95 FFRs, only one step, aimed at inhibiting various pathogenic microorganisms, is performed; therefore, it seems more accurate to use the term “disinfection”.
Given the COVID-19 pandemic and the potential shortage of N95 FFRs, the CERDM evaluated the available options for disinfecting these N95FFRs. This effort is aimed at identifying alternative strategies that can be added to the measures already available, to provide the best possible protection for health care workers in the event of a shortage. Thus, control measures that differ from those which are usually accepted may be implemented alone or in combination. These measures are unprecedented and highlight the need for the various authorities to develop solutions to respond proactively to an anticipated shortage of N95 FFRs1 and to be able to distribute them to workers during a real shortage of N95 FFRs.2
Given this context, the Comité des infections nosocomiales du Québec (CINQ) issued interim recommendations concerning the reuse of N95 FFRs (by the same user) and for their rational use (INSPQ, 2020a,b). Disinfection of N95 FFRs is a solution of last resort, in the absence of other alternatives. In addition, under the Interim Order Respecting the Importation and Sale of Medical Devices for Use in Relation to COVID-19, Health Canada has authorized the disinfection of N95 FFRs by means of various disinfection devices (Health Canada, 2020a). A summary of the technologies and equipment approved by Health Canada is presented in a document produced by the CERDM (INSPQ, 2020c).
The present document analyzes current knowledge about available disinfection options for N95 FFRs and puts into perspective the advantages and limitations of each disinfection process identified. The authorizations that have been issued by regulatory authorities are also specified. Finally, the recommendations of the CERDM are presented.
1 Strategies to be applied in the event of an anticipated shortage, but while supplies are available (after verification with the procurement department and the Ministère de la Santé et des Services sociaux (MSSS)).
2 Strategies to be applied in the event of a known shortage (after verification with the procurement department and the MSSS).