Introduction

The outbreak of COVID-19 has changed the way we deal with our everyday life: we are all doing our best to protect ourselves and others from the spread of the virus following the WHO’s advices (World Health Organization), by using appropriate Personal Protection Equipment (PPE) and by sanitising shared spaces (here you can read the general European guidance for cleaning and disinfecting environments).

For most of the people, using PPE is quite a new thing and, despite being available in different types, lots of them are disposable and not reusable.

Here we are listing and describing a series of answers on how to clean and therefore reuse, these PPE, so that they don’t go to waste.

We have divided the information below according to the different types of PPE available, in order to make it a bit more clear and diversified to the reader.

Recommendation on finding ways to clean and reuse PPEs.

N95 Facial Masks

Disposable filtering facepiece respirators (N95 facial mask) are very popular as PPE, but they are not meant for routine decontamination and reuse as standard of care. However, their decontamination and reuse may need to be considered as a crisis capacity strategy to ensure continued availability.

Stanford University has investigated three promising disinfection methods that may be applied to the recycling and reuse of N95 facial masks: hot air (75 °C, 30min), UV light (254 nm, 8W, 30 min), and steam (10 min). Those treatments seem not to deform mechanically or ear straps retain elasticity for the use of N95 masks.

Moreover, the first two disinfection methods do not reduce the filtration efficiency of the melt-blown layer after an appreciable number of treatment cycles. Here you can read the complete work-in-progress report.

Also, CDC (Centers for Disease Control and Prevention) gives a useful guideline for decontamination and reuse of filtering facepiece respirator.

Homemade Face Masks

Cloth face masks are a very practical solution for those who lack PPE availability, although ECDC (European Centre for Disease prevention and Control) does not consider their use as protection against respiratory viruses.
Indeed, in the context of severe PPE shortage, homemade cloth masks are proposed as a last-resort: to sew them for personal use, at this link you can find a very useful material list.

But are they reusable?
The answer is yes: ECDC technical report determines the correct ways to sanitize cloth masks to then reuse them.

Also in the general European guidance listed above we can find the procedure to clean and disinfect masks made by textiles, and here’s a resume: hot-water cycle (90°C) and regular laundry detergent. Alternative: lower temperature cycle + bleach or other laundry products.

3D printed PPE

Since the beginning of the spread of the virus, maker communities have started to cope with the Covid-19 emergency.
Thanks to digital fabrication laboratories, they have started to find good PPE solutions (face shields and respirator masks) mostly by using 3D print machines and plastic materials.

Face shields are very popular as protective equipment for doctors and other professionals during Covid-19 crisis.
In this guideline, released by Prusa, there is a step by step cleaning for the shield and recommended methods to kill the virus on PETG material (alert: if you are using other materials, we cannot guarantee those methods are efficient as well due to different properties).

Elastomeric Respirator masks are partial-face covering masks with removable filter elements designed to be re-usable.
The plastic parts can be cleaned and decontaminated by using the same method recommended for the Face shields above, instead the filter must be replaced.
In this guideline there are useful methods to sanitize your respirator mask.