COVID-19 medical masks and respirators: Reprocessing N95 respirators

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• Using reprocessed N95 respirators
• Regulatory requirements for reprocessing N95 respirators
• Decontamination in hospitals and health care settings

Using reprocessed N95 respirators

N95 respirators are a type of disposal filtering facepiece respirator (FFR), designed and labelled for single use by the original manufacturer.

The U.S. National Institute for Occupational Safety and Health (NIOSH) evaluates, tests and certifies N95 respirators.

Health Canada, the regulator for medical devices in Canada, accepts the NIOSH certification as an appropriate quality standard for N95 respirators. The Canadian Standards Association (CSA) Group launched a certification program in October 2020, which provides an alternative to NIOSH for Canadian manufacturers of FFRs. Respirators certified through this program will be designated 95PFE.

While it is preferable to use a new N95 respirator each time it is required, due to critical shortages, Health Canada has approved various decontamination methods for the reprocessing of single use N95 respirators. The intention is to extend the usability of compatible N95 respirators through reprocessing and reuse to provide the option of continued availability of these devices as a contingency measure during the COVID-19 pandemic.

Testing of reprocessed N95 respirators

Reprocessed N95 respirators:

• can achieve a seal around the nose and mouth
• are tested to confirm 95% or greater particulate filtration efficiency against small non-oil based particles  the size of bacteria and viruses

However, reprocessed N95 respirators:

• may not meet all of the original equipment manufacturer (OEM) specifications
• are not considered re-certified as an N95 respirator, that is, they will not be considered NIOSH-approved

The regulatory review of decontamination medical devices (Class II) considers the:

• effects of the decontamination processes on both the:
  • filtration performance
  • viricidal/sporicidal decontamination effectiveness for the respirator
• maximum number of decontamination cycles recommended

The maximum number of cycles recommended is based on the performance of the N95 respirator, including filtration efficiency and the ability to achieve an adequate fit or seal.

Reprocessed N95 respirators are not retested for fluid resistance.

Some manufacturers are conducting their own testing to evaluate the effect of decontamination methods. Health Canada encourages contacting OEMs directly for reprocessing advice or testing conducted specific to their devices. For example, 3M recently published the 3M Decontamination Methods for 3M Filtering Facepiece Respirators (FFRs). This bulletin presents NIOSH-based testing on their FFRs following reprocessing with several reprocessing devices currently approved for use.

Health Canada advises that reprocessed N95 respirators meeting safety and effectiveness requirements can be used for aerosol generating medical procedures (AGMP) when:

• correctly fitted and
• used with other appropriate personal protective equipment (PPE) such as:
  • hoods
  • gowns
  • face shields

However, this should only be considered as a contingency measure, based on a point-of-care risk assessment (PCRA).

Limitations on the reprocessing of N95 respirators

Both new and reprocessed N95 and N95 equivalent respirators have not been approved for use after an AGMP.

N95 respirators that have been used for AGMP or that are soiled should never be reprocessed.

The manufacturer's labelling of reprocessed respirators directs users to check for soiling following use. The risk of soiling is higher in AGMPs.

Also, as SARS-CoV-2 (the virus causing COVID-19) is a novel virus, validation evidence for each decontamination processes includes:

• worst-case bacterial sporicidal testing evidencing a 6 log reduction for the chosen reprocessing method
• viral inactivation testing (4 log reduction) including:
  • H1N1, MERS-CoV, SARS-CoV, SAR-CoV-2, Influenza A/PR/8/34
  • surrogates (Risk Group 2 (RG2) bacteria or viruses as surrogates, or other microorganisms, not required to be handled in Containment Level 3 (CL3) laboratories can be considered)

You can find a list of N95 respirators and equipment used in the decontamination of N95 respirators authorized under the Interim Order on Health Canada's website.

Reprocessing of N95 respirators

Currently, respirators containing cellulose or latex are not recommended for decontamination. Additionally, there is no evidence to support the decontamination of:

• surgical masks
• N95 respirator equivalents such as KN95 respirators or FFP2 respirators

There are currently no Interim Orders issued for the reprocessing of N95 respirator equivalents. This guidance applies exclusively to reprocessed N95 respirators.

For information on Health Canada's requirements for reprocessed respirators, please see the notice on Reprocessing of Single Use N95 Respirators during the COVID-19 Response.

All reprocessed N95 respirators must be labelled and clearly marked as being reprocessed with the name and address of the reprocessor. This clear identification is also recommended for health care facilities conducting decontamination processes on-site. This labeling should also indicate how many times the N95 respirator has been reprocessed and come with an instruction sheet for the end user.

This document is not meant to replace processes, procedures or guidelines established by provinces and territories and their health care facilities with regard to reprocessing and decontamination on-site by hospitals.

It is the individual end user's decision to use a reprocessed N95 respirator in accordance with their point-of-care risk assessment (PCRA).

The Public Health Agency of Canada continues to recommend the use of certified N95 respirators in accordance with the manufacturer's directions. However, in response to critical shortages, there are important considerations for use of reprocessed N95 respirators.

Key considerations for use of reprocessed N95 respirators

To reduce the risk of infection, health care facilities using reprocessed N95 respirators should, in addition to following the instructions provided by the manufacturer:

• develop clearly written procedures and provide education to staff to ensure that staff:
  • avoid touching the front of the respirator
  • perform hand hygiene before and after touching or adjusting the respirator
  • discard respirators that are visibly contaminated with fluids, blood or respiratory secretions

Health care facilities should also:

• maintain supply separation between reprocessed N95 respirators and certified N95 respirators
• identify and clearly mark separate areas for clean reprocessed and used reprocessed N95 respirators
• clearly label reprocessed N95 respirators as reprocessed and include instructions that indicate that they:
  • may not meet all the OEM specifications
  • are not re-certified as an N95 respirator, that is, they will not be considered NIOSH-approved

When using a reprocessed N95 respirator, it is recommended that the end user undertake the following measures:

• verify that the user's name is on the respirator, either on the elastic or on the inside or outside of the respirator, labelled with permanent marker or tags
• if selecting from a pool of clearly identified reprocessed respirators, select an N95 respirator model for which they have been fit tested
• verify that the number of reprocessing cycles has not exceeded the recommended cycle threshold as determined by the reprocessor or N95 decontamination device manufacturer
• complete a visual inspection of the respirator that includes:
  • the facepiece of the respirator to ensure all original labels are still visible and legible
  • the facepiece of the respirator to identify any visible damage such as:
    • holes
    • tears
    • deformations
    • delamination
  • the head harness (the head straps) to ensure they are attached to the facepiece of the respirator and that they fit properly as head straps may be stretched by different users
  • the nasal splint (if applicable) to ensure it is properly in place and not protruding out of the facepiece of the respirator. If nose pieces have been bent, it may be more challenging to achieve a fit.

The respirator should be discarded if the integrity of any of its parts are compromised or it becomes hard to breathe through.

It is recommended that the end user conduct a seal check (in accordance with CAN/CSA Z94.4) immediately after donning. For reprocessed N95 respirators that no longer pass a leakage test, the labelling recommends discarding them.

Regulatory requirements for reprocessing N95 respirators

In response to the COVID-19 crisis, Health Canada introduced new interim regulatory measures to expedite the review of medical devices. These measures include regulatory requirements for 2 separate authorization strategies for reprocessing single use N95 respirators:

• authorize reprocessing devices that are manufactured and sold to decontaminate N95 respirators
• authorize companies to reprocess and distribute decontaminated N95 respirators to health care facilities

Please refer to the Reprocessing of Single Use N95 Respirators Notice for an outline of the regulatory and application requirements. As with all COVID-19 related products, Health Canada is expediting applications for these products and making them our top priority.

To obtain further information regarding medical device licensing, please contact the Medical Devices Directorate at devicelicensing-homologationinstruments@hc-sc.gc.ca.

Decontamination in hospitals and health care settings

The considerations for use of reprocessed respirators apply to all circumstances where health care facilities are reusing such devices through:

• the use of on-site decontamination facilities
• contracting with an authorized reprocessor

Health Canada authorization is not required if:

• hospitals are decontaminating N95 respirators within their institutions for their own re-use
• hospitals are decontaminating N95 respirators from an external institution and sending the respirators back to the same institution

However, if a hospital is decontaminating N95 respirators obtained from an external institution and sending the respirators to a different institution, then this becomes a regulated activity. In such cases, the institution can apply under the Interim Order No. 3 respecting the importation and sale of medical devices for use in relation to COVID-19 to become a reprocessor.

A device manufacturer could apply for an Interim Order authorization for their decontamination device and sell it to a hospital to use as outlined in the Reprocessing of Single Use N95 Respirators Notice.

Health Canada will continue to:

• respect the current oversight provided at the provincial and territorial level and guidance provided by the Public Health Agency of Canada.
• build on the collaborative work with the provinces and territories on procurement and allocation of personal protective equipment (PPEs)
• make information on authorizations available in a timely manner

Related links

• Technical requirements for UV decontamination devices: Notice to manufacturers
• Notice - Important regulatory considerations for the reprocessing of single use N95 respirators during the COVID-19 response
• Reprocessing of N95 respirators for health care professionals - Notice
• Notice to stakeholders - Health Canada's regulatory approach to commercial reprocessing of medical devices originally labelled for single use