Is there a certain number of fire alarm sensors required per floor or per area? I can't seem to find an answer in big red, the onsite guide or the guide to the building regs.
You won't find it, 7671 does not apply to fire alarm applications this is a different standard, but I can't remember the no. now even thought I have a copy as I dabble a little!
If the system is to be zoned to BS5839-1. Then you shouldn't really have any more than 15 detectors per zone, and a single zone should not exceed a floor area of 2000 metres square.