See https://registeredgasengineer.co.uk/technical/co-alarm-rules-for-properties-across-the-uk/
CO-Gas Safety is an independent registered charity which works to try to reduce deaths and injuries from unintentional Carbon Monoxide (CO) poisoning and other gas dangers. We lobby for changes, which will help to achieve this. We also help and advise victims/survivors and families affected whenever we can.
This charity runs almost entirely on volunteers and relies on donations. Please donate to save lives and preserve health.