Live in a council house which has gas CH installed in Nov last year - just a boiler upstairs and heating . The council did stick in a CO alarm upstairs at the time . They’ve stuck it on the ceiling beside the bedrooms - think it had to be ceiling mounted or something as they’re all wired in/connected with a test socket downstairs .
Googling just now apparently it should be lower down instead - as CO sinks - I can’t move it myself but is it worth asking the council ? Never thought much about it before but it was mentioned on TV just now and not sure .