BMRA has been alerted to a new scam comprising BEIS-headed letters being sent to businesses advising them that, by law, they need to purchase air purifiers to comply with #COVID19 rules. This is not true. 
 
This Tweet by BEIS https://twitter.com/beisgovuk/status/1384458801764392963 has more info and a reporting address.
 
An example of the letter can be seen below.