Face masks become less effective in the rain - here’s what experts are saying

The effectiveness of face masks lessens when they get wet, the World Health Organisation (WHO) and other health experts have warned.

A number of experts have now stated that if face coverings become damp, they need to be replaced. They have called for government officials to provide the public with “clear advice” on this matter.

Change wet masks

People are required to wear a face covering in shops, supermarkets and on public transport in the UK, alongside a host of other places, but it is not compulsory to wear face coverings when outdoors in the UK, for example when walking between different sites.

WHO guidance explains that face masks which get wet should be replaced straight away.

“For any type of mask, appropriate use and disposal are essential to ensure that they are as effective as possible and to avoid any increase in transmission,” says the WHO.

“All masks should be changed if wet or visibly soiled; a wet mask should not be worn for an extended period of time. Replace masks as soon as they become damp with a new clean, dry mask.”

The official guidance from the Department of Health and Social Care also explains that the public should "change the face covering if it becomes damp or if you’ve touched it."

Public should be given advice about wet face coverings

Tim Spector, professor of genetic epidemiology at King’s College London, told The Times, “It would now be useful if clear advice were issued to the public.

“Masks need to be changed regularly and this is particularly important to understand in damp and wet weather.”

Aseem Malhotra, a consultant cardiologist, added, “It is obvious that masks will get damp as people shop and travel in bad weather.

“There has been no public campaign to make people aware that this can make their masks ineffective.”