The effectiveness of UVC rays on FFR breathing masks

The lack of supply of FFR breathing masks for health workers is a major problem in this health situation. This is why research is ongoing to assist teams dealing directly with infectious respiratory diseases where aerosol transmission is possible.

UVC rays to promote the reuse of FFR breathing masks

The effectiveness of UVC rays on surfaces has already been proven. However, it was not clear yet whether it was possible to eradicate viral agents on reusable supplies whilst maintaining their integrity.

There are several things to consider:

• The dose of UVC needed to fully disinfect the equipment;
• The effects of UVCs on FFR breathing masks;
• The methodology to be used to disinfect masks.

The dose of UVC needed to disinfect FFR breathing masks

Numerous studies have shown that an appropriate dose of UVC would allow to disinfect masks without altering their integrity. (1.2.3)

If we rely on a log 3,it would take a dose of 1000 mJ/cm2 or more to eradicate the pathogen present on FFR breathing masks. This result is much higher than for conventional disinfection of surfaces, where a dose of 7 mJ/cm2 is sufficient to eradicate 99.9% of the viruses and bacteria present.

Indeed, masks are not surfaces per se since they are porous and their thickness can sometimes reach up to 3 mm. UVCs must thus be able to entirely penetrate the mask to render it devoid of any viral agents.

For more information about the virucidal and bactericidal effects of UVCs in different environments.

The effects of UVCs on the performance of FFR breathing masks

UVC rays are known for their effectiveness in eradicating cells on equipment and surfaces. It is therefore essential to take their effects on the performance of breathing masks into account.

Despite the limited information available on this subject, results indicate that a dose of UVC of up to 5000 mJ/cm2 did not affect either the filtration parameter of FFR breathing masks, or their overall appearance. Only occasional elastic fastener problems were mentioned.

The methodology for UVC disinfection of FFR breathing masks

Throughout the various studies conducted, several options are possible:

• A UVC germicidal lamp powerful enough, depending on the distance needed to reach the FFR breathing masks;
• A UVC germicidal lamp in the form of a closed unit with dedicated slots to hang FFR breathing masks.

In all cases, the UVC dose must be calculated before any use of the device. Indeed, otherwise, we cannot guarantee the safe eradication of FFR breathing masks without affecting their proper functioning.

Disinfecting the premises of your company is also paramount in ensuring the health of your staff, discover our article on this subject.