carbon monoxide & smoke detectors

[mikep]

where can I find it printed that a carbon monoxide detector must be fitted on a house let when they are re-wired.

I have had a quick look through BS5839 and cannot find it.

Or is there any other bits of reading on this.

Thanks all. Mike.

 

[batty]

Crazy but not law.

 

[spinlondon]

CO detectors are optional.