The government is warning people they could increase their risk of spreading Covid-19 if they use face masks incorrectly.
The National Public Health Emergency Team is set to recommend homemade masks be used on public transport and in shops.
Health chiefs will advise people to use their own coverings not medical masks.
But government official Liz Canavan says people need to be careful they use them properly.
"Work is ongoing around guidance and practical communications about the nature of the face coverings and how people might make those for themselves," said Ms Canavan.
"A key message will be around how to safely use face coverings because the evidence is clear that if face coverings aren't used properly, they can have the effect of increasing the risk of transmission.
"We expect to have further information for the public in the coming days in relation to this."
