Smoke Detector Wiring

[bilbo_88]

Hi All

Just a quick one. Recently had a job to install inter linked smoke detectors in the communal area of a house converted to 2 flats. Health and safety requested standard mains powered smokes with interlink.

I wired this through floors in T+E as I would in a standard domestic property, but have been pulled by another electrician stating it has to be in FP200. I have wired these from the lighting circuit (also wired in T+E) and used radio link bases so wiring it in FP200 seems pointless and pretty harsh reason to fail an EICR?

Any opinions and reg references are appreciated

 

[westward10]

Think we are at odds with different Regs, I get the cable fixing bit but it is the use of flame propagating materials on an escape route can't check it out at the moment.

 

[Midwest]

Last NIC/Elecsa 'web in air' vid I watched, Cable & Stantiforth stated the use of 'plastic plugs' were still deemed to be acceptable in such situations, it was the 'clip or fixing' that has to be metal or fire resistance. Seems, their advice comes from some document or study, suggesting the plastic rawplug, would survive fire due to the surrounded concrete or brick structure.

Once again, these 'organisations & bodies' need to have some sort of joined up thinking, and stop offering conflicting guidance.

Or is it the case, some manufactures sense a marketing opportunity.

 

[Octopus]

Once again, these 'organisations & bodies' need to have some sort of joined up thinking, and stop offering conflicting guidance.

I've just seen a pig flying past the window.... and IF, I say IF the IET got its act together, the "variety" of interpretations wouldn't be required..

 

[Midwest]

I've just seen a pig flying past the window.... and IF, I say IF the IET got its act together, the "variety" of interpretations wouldn't be required..

We can all live in hope, even in utopia

 

[westward10]

That regulation mentions absolutely nothing about flame propagating systems just supports.
Pvc containment is not prohibited as long as cables have metallic supports to prevent premature collapse.
Regulation 422.2.1 which can mean LSoH cables

422.2.1 states wiring systems shall be non-flame propagating. It is there in black and white.

 

[Wilko]

Fresh back from a few days away, I'm tempted to ask "so would normal cable be flame propagating ? "
Fire rated cables I get, but is that the same as non flame propagating ?
May need to duck off back to Heidi Land

 

[westward10]

Think people are so blinded by Am 3 and fire resistant fixings they ignore the requirements for cable systems on escape routes and T&E most certainly would not comply even if it were fixed with indestructible clips. Comment frequently when doing FRAs on this type of thing.

 

[bilbo_88]

Ok great, thanks for all your advice guys. And for those who were asking it was a grade D system

 

[Ian1981]

Try non fire propagating pvc conduit to bs en 61386-1
Bs en 50085
Bs 4607
All expectable in escape routes.

Winner rating??
Are we still in school??

 

[Wilko]

Reading that 422.2.1, towards the end it does say for BD2/3/4 the wiring systems shall be fire rated... (edit : just read Ian post #24 )
I did set fire to a cable to see what happened - not as bad as I'd hoped thought with the cable self extinguishing within about 10sec. Not surprising it failed IR testing after meeting Mr Rothenberger. Now for the pics

 

[Ian1981]

Reading that 422.2.1, towards the end it does say for BD2/3/4 the cables shall be fire rated...
I did set fire to a cable to see what happened - not as bad as I'd hoped thought with the cable self extinguishing within about 10sec. Not surprising it failed IR testing after meeting Mr Rothenberger. Now for the pics

View attachment 36346

Try that with LSOH cable which is non fire propagating and will not give off the fumes standard twin & earth will

 

[westward10]

Ok great, thanks for all your advice guys. And for those who were asking it was a grade D system

So what did the EICR say.

 

[bilbo_88]

So what did the EICR say.

FP200 not used for smoke detectors- C2

Had no regulation reference or anything

 

[Ian1981]

FP200 not used for smoke detectors- C2

Had no regulation reference or anything

Potentially dangerous???

 

[Octopus]

Potentially dangerous???

No - C3 maybe?