COVID-19: Collection, Disinfection and Storage Processes for Single-Use N95 Filtering Facepiece Respirators
This publication uses the term "disinfection" of 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).
This document is intended for managers and clinical personnel involved in medical device reprocessing (MDR).
Its purpose is to describe the guidelines to be followed for the overall process of collecting, disinfecting and storing N95 filtering facepiece respirators (FFRs) (also known as N95 masks) in order to :
- Ensure the safety of personnel.
- Ensure compliance with and implementation of infection prevention and control (IPC) measures associated with disinfection activities.
- Ensure compliance with the disinfection procedures for used N95 FFRs as per the manufacturer's instructions for the technologies chosen to perform the disinfection.
- Standardize the process for disinfecting used N95 FFRs.
The CERDM evaluated the available options for disinfecting used N95 FFRs in the context of the real shortage of these devices in health care facilities during the COVID-19 pandemic (INSPQ, 2020a). Currently, Health Canada has authorized the following manufacturers' technologies for the disinfection of N95 masks under the Interim Order regarding the use of medical devices in relation to COVID-19 (Health Canada, 2020) (INSPQ, 2020b): low-temperature sterilizers (Sterrad from the company ASP (2020), Sterizone/VP4 from the company Stryker (2020) and V-Pro from the company Steris (2020)), the hydrogen peroxide vaporizer (room disinfection device) (Bioquell from the company Ecolab) and the disinfection device combining several technologies (UVC, vaporized hydrogen peroxide and ozone) (Clean Flow Health Care Mini from the company Clean Works Medical). This evaluation process falls within the context of efforts to identify alternative strategies that would provide the best possible protection for workers in the event of a shortage. Alternative control measures that differ from the usually accepted measures must be implemented alone or in combination (CDC, 2020). These measures are unprecedented and highlight the urgent need for the various authorities to develop immediate solutions in order to proactively respond to a real shortage of N95 FFRs (INSPQ, 2020a).
Precautions to be considered
Special care must be taken when using technology for disinfecting N95 FFRs since the protocols provided by the companies can only be applied to certain models of masks. For example, N95 FFRs containing cellulose or paper are not compatible with disinfection by hydrogen peroxide (ASP 2020, Steris, 2020, Stryker 2020).
Different manufacturers' instructions may vary, so it is important to follow those specific to the equipment being used.
With regard to the concept of a single wearer for an N95 mask, manufacturers' instructions can vary (from highly recommended to required). The CERDM recommends following the instructions of the manufacturer of the technology used. However, such an approach could represent a significant logistical challenge, affecting process performance and mask availability. The decision as to whether or not there should be a single wearer should be determined by health care facilities through an internal risk management assessment.
CA Collection Attendant
CERDM Centre expertise en retraitement des dispositifs médicaux (a centre of expertise in medical device reprocessing)
DINDrug Identification Number
HCW Health Care Worker
IPCInfection Prevention and Control
MDR Medical Device Reprocessing
MDRA Medical Device Reprocessing Attendant
MDRD Medical Device Reprocessing Department
N95 FFR N95 Filtering Facepiece Respirator
PPE Personal Protective Equipment
UV Ultraviolet Irradiation
The medical device reprocessing department (MDRD) is responsible for developing a disinfection procedure in accordance with the manufacturer's instructions for the technology used to perform disinfection of N95 FFRs (UV device, hydrogen peroxide vaporizer, low-temperature sterilizer) and with the information provided in this document.
The IPC department collaborates on validation of the facility's procedures tied to the disinfection of N95 FFRs.
It is recommended that the disinfection process for used single-use N95 FFRs be carried out in accordance with the following recommendations.
Health care worker
Donning the N95 FFR
- The health care worker (HCW) retrieves the new N95 FFR from the facility's designated storage location.
- Using a permanent marker (only a permanent, soft-tipped marker that has been validated for use with the chosen sterilization process should be used) (CSA, 2018), the HCW writes the necessary information on the front of the N95 FFR, including date, department or unit, first name and surname. This ensures that the disinfected FFR is returned to the right HCW and to the right place. The date of use is required to monitor the duration of use as well as the number of decontamination cycles. If the use of N95 FFRs is not limited to a single user following a risk management assessment by the health care facility, the HCW should only indicate the date of use (see the Context-Precautions section).
- The HCW carries out a summary inspection of their N95 FFR to confirm its integrity (no soiling or damage) before donning it.
- The HCW dons their N95 FFR in accordance with the established procedure to ensure a proper fit. If the fit check reveals that the fit is inadequate, the HCW should discard the mask and obtain a new one.
- The HCW uses their N95 FFR in accordance with the established guidelines for use.
Doffing the N95 FFR
- The HCW doffs their N95 FFR in accordance with the established guidelines.
- The HCW conducts an initial summary inspection of the N95 FFR and must discard any mask with visible soiling or damage in a designated container.
- The HCW places their used N95 FFR in a brown paper bag (CDC, 2020), making sure that the brown bag is properly labelled with the full name of the HCW and the return location of the department/unit, if applicable.
- The HCW deposits their brown bag (side-by-side others) in a labelled transport container dedicated to the collection of used N95 FFRs, in a designated storage location in a soiled utility area. The HCW makes sure to leave the lid of the transport container open.
- The HCW performs hand hygiene in accordance with the established internal procedure using either soap and water or a hydroalcoholic solution (HS).
- The collection attendant (CA) must put on clean gloves to carry out their task. The CA ensures the collection of all transport containers labelled "Used N95 FFRs." The CA must carry out an external disinfection of the transport container.
- The CA places the disinfected transport container on a transport cart dedicated to the transport of soiled material. The CA takes the cart to the dedicated room of the decontamination unit. Only gloves must be worn for this process. Warning: the wearing of personal protective equipment (PPE) is required if going through a containment zone.
- The CA places the transport containers on the designated shelf in the dedicated decontamination room.
- The CA removes the gloves and performs hand hygiene using either soap and water or a HS.
- The CA records the requested information on the activity log sheet (name and contact number of the drop-off person, location of department/unit, name and number of the person to contact for pick-up).
Decontamination room for the storage, sorting and bagging of used N95 FFRs
- Ventilation requirements for the decontamination room dedicated to the storage, sorting and bagging of N95 FFRs are the same as for the decontamination room of the MDRD, i.e. negative pressure, a minimum of 10 air changes per hour completely evacuated to the outside and a temperature maintained between 18°C-20°C.
- If it is impossible to obtain a dedicated room for this purpose, these activities could be carried out in the decontamination room (soiled area) of the MDRD by providing a dedicated space.
- It is important to avoid any cross-contamination between the usual activities of the MDRD and the disinfection of the used N95 FFRs.
Medical device reprocessing attendant
N95 FFR reception/inspection
- The medical device reprocessing attendant (MDRA) acknowledges receipt of containers of used N95 FFRs in the activity log.
- The MDRA puts on their usual PPE (protective gown, gloves, mask, eye protection, head and shoe covers).
- The MDRA retrieves the containers of used N95 FFRs while avoiding touching other surfaces to avoid environmental contamination.
- The MDRA transfers the brown bags containing the used N95 FFRs, grouped by location, to a cart and brings them to the dedicated decontamination room.
- The MDRA opens one brown bag at a time and takes out the N95 FFRs one at a time. They then check the name, location and date on the N95 FFR.
- The MDRA performs a second inspection of each N95 FFR to detect any anomalies. If damaged, soiled or damp, the mask must be discarded in a designated container.
- The MDRA validates the number of disinfection cycles indicated on the N95 FFR. If the number of disinfections has been reached, the mask must be discarded in a designated container. The number of authorized disinfection cycles is specified in the manufacturer's instructions for the technology used to carry out the disinfection (ASP 2020, Steris, 2020, Stryker 2020).
- The MDRA disinfects the transport containers and surfaces with a low-level disinfectant authorized by Health Canada (DIN), with broad-spectrum virucidal action (Government of Canada, 2020).
Pre-processing drying time
- A drying period of at least one hour before disinfection is recommended depending on the length of time between end of use and collection. Either of two options may be chosen :
- The period between end of use and collection is more than one hour and the storage conditions are respected (masks are placed in a brown bag and the bags are placed side by side in an open container), in which case the drying period is sufficient.
- The period between end of use and collection is less than one hour, in which case it is recommended that there be a drying period of at least one hour following inspection of the masks. Inspected masks should be placed on a grid shelf for drying.
Disinfection of N95 FFRs
- The MDRA disinfects the used N95 FFRs by strictly following the established procedure included in the manufacturer's instructions for the technology used (ASP 2020, Steris, 2020, Stryker 2020).
- If disinfection is performed using low-temperature sterilization, the MDRA must comply with the following additional precautions (dedicated sterilizer, IPC measures and surface cleaning) :
- Place the N95 FFR and a chemical indicator in a self-sealing Tyvek type sterilization pouch, avoiding external contamination during handling. The plan should be to use the two-person technique (one MDRA places the used and inspected FFR in the pouch while another MDRA holds the pouch with clean gloves and seals the pouch).
- Place the bagged masks in a container on a disinfected and covered transport cart.
- Disinfect transport containers belonging to the work units and work surfaces using a low-level disinfectant with broad-spectrum virucidal action (Government of Canada, 2020).
- Remove PPE and perform hand hygiene using either soap and water or a HS.
- Perform hand hygiene using either soap and water or a HS and put on gloves before entering the MDRD.
- Bring the transport cart containing the bagged masks directly to the dedicated sterilizer in the MDRD to avoid cross-contamination of the environment.
- Load the bagged masks and perform quality controls of the load in accordance with the sterilizer manufacturer's instructions.
- Once loading is completed, the MDRA disinfects the cart and the surfaces they have touched, using a low-level disinfectant with broad-spectrum virucidal action (Government of Canada, 2020).
- Remove gloves and perform hand hygiene using either soap and water or a HS.
- The MDRA fills out the quality control log (date, time, load number, load content, quality control results associated with the technology used).
- The MDRA inspects the reprocessed N95 FFRs and must dispose of any mask with visible soiling, damage or moisture in a designated container.
- The MDRA ensures that the aeration time for the reprocessed masks is respected.
Post-disinfection aeration time
- An aeration period of 24 hours is recommended for N95 masks following the disinfection cycle, with the pouch closed. This recommendation is applicable to the instructions of the three low-temperature sterilizer companies (ASP, Steris, Stryker) based on the results of the study conducted by the Institut de recherche Robert-Sauvé en santé et en sécurité du travail (IRSST, 2020).
Storage of N95 FFRs
- Low-temperature sterilization technology: the MDRA deposits the reprocessed N95 FFR pouches in a new disinfected transport container, indicating the user's name and the return location on the outside of the transport container. They add new brown bags for the return of used N95 FFRs. During storage, the container holding the N95 FFRs must remain open.
- UV or vaporous hydrogen peroxide technology: the MDRA deposits the disinfected N95 FFRs in a new white paper bag, indicating the user's name and the return location on the outside of the white bag. They add new brown bags for the return of used N95 FFRs. They make sure the transport container is securely closed.
- The MDRA ensures distribution takes place in accordance with the established internal procedure.
N.B. Designated storage areas must be provided for the storage of disinfected N95 FFR containers to protect them from all contamination, moisture and soiling.
- Advanced Sterilization Products (ASP) (2020). Instructions for Healthcare Facilities: Emergency Decontamination of Compatible N95 or N95-equivalent Respirators in STERRAD® Sterilization Systems. April 2020. Retrieved from https://www.asp.com/sites/default/files/covid-19/STERRAD_HCF_FDA_041120.pdf (last consulted online on April 20, 2020).
- Centers for Disease Control and Prevention (CDC). (2020). Coronavirus Disease 2019 (COVID-19). Decontamination and Reuse of Filtering Facepiece Respirators. Retrieved from https://www.cdc.gov/coronavirus/2019-ncov/hcp/ppe-strategy/decontamination-reuse-respirators.html (last consulted online on April 15, 2020).
- CSA Group. Canadian medical device reprocessing. Z314-18. February 2018
- Government of Canada (2020). List of hard-surface disinfectants authorized by Health Canada (COVID-19): Retrieved from https://www.canada.ca/en/health-canada/services/drugs-health-products/disinfectants/covid-19/list.html (last consulted online on April 2, 2020).
- Institut national de santé publique du Québec (INSPQ) (2020a). CERDM. COVID-19: Evaluation of Disinfection Options for N95 Filtering Facepiece Respirators in the Context of the Pandemic. Retrieved from https://www.inspq.qc.ca/en/publications/2971-disinfection-n95-covid19
- Institut national de santé publique du Québec (INSPQ) (2020b). CERDM. COVID-19: Disinfection of N95 Single-Use Filtering Facepiece Respirators. Retrieved from https://www.inspq.qc.ca/en/publications/2966-disinfection-N95-single-use-facepiece-respirators-covid19
- Institut de recherche Robert-Sauvé en santé et en sécurité du travail (IRSST) (2020). Recommandation sur le temps d’aération des appareils de protection respiratoire de type N95 après désinfection à la vapeur de peroxyde d’hydrogène dans un stérilisateur à basse température. Retrieved from https://www.irsst.qc.ca/covid-19/avis-irsst/id/2733/recommandation-sur-le-temps-daeration-des-appareils-de-protection-respiratoire-de-type-n95-apres-desinfection-a-la-vapeur-de-peroxyde-dhydrogene-dans-un-sterilisateur-a-basse-temperature
- Lowe J.J., Paladino K. D., Farke, J. D. et al., N95 Filtering Facemask Respirator Ultraviolet Germicidal Irradiation (UVGI) Process for Decontamination and Reuse. March, 2020. Nebraska Medicine
- Steris (2020). Instructions for Healthcare Facilities: Decontamination of Compatible N95 Respirators Using the STERIS Sterilization Systems. April, 2020. Retrieved from https://www.steris.com/healthcare/steris-decontamination-solutions-for-compatible-n95-or-n95-equivalent-respirators
- Stryker (2020). Instructions for MDRD workers’ decontamination of N95 respirators with sterizone/VP4 sterilizer. D-1616_00_N95 respirators reprocessing Instructions_MDRD workers
In accordance with your MDRD’s procedures.
1.0 (in French only)
|2.0 (in French only)||2020-04-16||
|2.1 (in French only)||2020-04-20||
The guidelines presented here are based on the latest information available at the time of writing. Given that the context of the COVID-19 pandemic and the authorizations issued by regulatory authorities for N95 mask disinfection equipment are evolving rapidly, the recommendations in this document are subject to change.
The CERDM would like to thank Mr. Simon Aubin of the IRSST, the IRSST team and the team from the Centre hospitalier de l'Université de Montréal (CHUM) for their involvement in the evaluation of post-disinfection aeration times.