Coronavirus: Why you might want to take a spare face covering when you're out in the rain

Credit: PA

Rain can limit the effectiveness of face coverings in protecting against Covid-19, the World Health Organization (WHO) has warned, adding they should be replaced in they become damp.

As the country moves in to autumn and we all suffer more frequent deluges, scientists are calling on the government to release a public information campaign to inform people how the wet weather impacts their face coverings and on the risks of wearing wet masks.

"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 WHO has said.

Official guidance from the Department for Health and Social Care (DHSC) explains that the public should "change the face covering if it becomes damp or if you’ve touched it."

Nicola Stonehouse, professor of molecular virology at the University of Leeds, told ITV News: "It is a good idea to change masks regularly in all circumstances. And damp masks are unlikely to be as good a barrier. But this generally refers to the dampness caused by our breathing i.e. dampness from the inside rather than outside."

There are different types of face covering for different occasions. For instance, the N-95 mask - considered to be the most effective at preventing infection, is used by surgical professionals.

The WHO says effective fabric masks should be made of three layers of different materials, but it warns moisture compromises this protection.

While disposable three-ply masks repel some naturally occurring moisture, such as from breathing, guidelines say they must be replaced if they get wet.

After the recent bouts of storms, 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."

Face coverings are are mandatory in shops and other settings in England from Friday Credit: Andrew Milligan/PA

Along with a host of other coronavirus measures, people in the UK are required to wear face coverings in a number of indoor settings, including in shops and on public transport.

While the rules on wearing a face mask indoors are strict, it is not compulsory to wear them outdoors, for instance when walking between shops.

The age at which you must wear a face covering vary between the UK nations; in Scotland, everyone over the age of five must wear one, those over 11 in England and Wales, and 13 in Northern Ireland.