There was some dopey twat on our village Facebook site saying they are disposing of some bedding "if anyone is making masks"!
I urged people to think again. Fucking home-made cotton masks, FFS?
As has been said early in this thread, PHE do not advise the general public to wear masks other than in specific circumstances (e.g. they are caring for a vulnerable relative who they live with). You MIGHT need them in SOME workplace scenarios where you can't maintain the 2m rule, but this should be based on a risk assessment and instruction from your employer.
That advice may yet change based on evidence as it emerges (but as David says, that research is not gospel), but in my view, it won't while there is such a shortage of masks for people who genuinely need them (e.g. NHS staff). What happened to the government reinforcing the message to CATCH IT in a tissue? You don't see people doing that, although they're scrubbing their hands till they bleed (again with no understanding of how or why!).
I see a few people wearing disposable gloves while going round the supermarket, but they then handle their car door handles, purse/wallet and their phone still with the gloves on, so they clearly have no idea what they are meant to be protecting.
And the people wearing random masks are just laughable - there is NO WAY that most of them are worn in such a way as to protect them.
(Incidentally, i train people in the correct use of PPE including masks, and am providing advice on a daily basis to the large organisation that employs me).