Since the beginning of the COVID-19 pandemic, most of us use two items on a regular basis. The first is hand sanitising products and the second is face masks.

In many cases these two items are our first line of defence against the virus. The only thing standing between us and it. But what if one of these two items had the potential to counteract the other so that it no longer worked?

That’s exactly the situation our researchers investigated in a recent study. Their research looked at the effects of alcohol-based sanitiser vapours on respirator filtration systems, specifically face masks.

Being filtration experts, they understood the technology behind the most commonly used disposable face masks, including the (K)N95 and P2 rated masks, relies on electrostatic charge.

A charge against COVID

Electrostatic charge is the result of friction between two surfaces. It’s what causes the ‘zap’ you sometimes get when touching someone or something. It also features in the famous rub-your-head-with-a-balloon-to-make-your-hair-stand-on-end party trick.

But did you know that this important mechanism is also embedded into your disposable face mask? It works by using an electrostatic field to attract pathogenic particles in the air. Thus, making them hit the surface of the mask’s web of fibres. A trapping mechanism (known as van der Waals forces) then works to capture the particles, trapping them like a sticky spider web.

This mechanism, however, can be weakened by fumes from the alcohols contained in many common sanitising products, like ethanol and isopropanol. Concentrated vapours from these products remove the electrostatic charge.

This kind of event could be disastrous during real-world pandemic mitigation practices. The disruption could possibly allow pathogens like COVID-19 to pass straight through a face mask and reach the wearer.

Investigating mask care in real-world scenarios

The pandemic has seen an increased use o