Number Of Smoke Detectors

Hi.....

would just like to sneak in my first two penneth........

Grade B systems require fire proof cable.......

Intruder systems come under Grade C.

To meet part 6 for Grade A,B,C,D systems (systems incorporating a central power supply or independent mains detectors incorporating battery backup) the standby supply has to last for 72 hours, hence the average security system won't comply unless you install a larger battery.

In domestics you need a minimum 85dB(A) at the bedroom door, 75dB(A) at the bed head only applies in BS5839-1 - commercial/hotels/boarding houses etc.

The average three bed semi, providing it is no higher than three storeys needs a Grade D minimum system - mains powered smokes/integral batteries, all linked together, Category LD2 - installed in all circulation areas forming part of the escape route, and in all rooms/areas that present a high fire risk to occupants.

As with all things these days, everything is risk assessment based and "you" need to decide the risk areas that need protecting.

But I do agree, getting to grips with domestic system design is a complete pain in the 'arris !!

Point proven - sticking with what I know (or at least can throw a reasonable shape at!).

Edited January 9, 200620 yr by Cerberus NI