At the moment, the advice in UK for members of public is unchanged, you don't have to wear a face mask or covering anywhere.
This changes in England from next Monday, we will have to wear a face covering in hospitals or on public transport. I am hoping that certainly in the former case, masks will be provided, and on public transport you can wear a simple face covering if nothing else available.
The WHO has recommended the over 60s and vulnerable wear a medical mask if social distancing cannot be avoided, i.e. shops, transport etc. As this is only a recommendation, which individual countries can take up or not, as they see fit, nobody will have to stay indoors if they can't get a mask.
Await developments here to see if BJ takes WHO up on this latest recommendation.
Regards Margaret