Fires caused by light fittings - Assistance Requested

[Jackbarnett_]

A client in Sydney recently suffered a fire loss and the fire brigade assessment is that the power factor correction capacitor in a light fitting started the fire – burnt onto the light diffuser in the fitting which then melted in flames and dropped to ignite the telephone, computer, desk and carpet below.

Although their electrical team have never seen anything likes this, they can't see another cause and the source of heat in the light fitting does appear to be where the capacitor would have been.

The light fittings were installed by News about 8-9 years ago during the fitout.

Whilst the clean-up is well underway, the company are seeking our advices as to whether there has been any incidence of this fire source across our client base.  They have also asked FM.  Any collaborating information would support a case for them to seek compensation from the manufacturer and would be greatly appreciated.

Regards,
Jack

[John Webb]

Can you give more information on the type of light fitting - batten, recessed in ceiling or whatever? Just that off hand, as far as the UK is concerned, I've never come across a power factor correction capacitor in a position where if alight it could spread fire to the diffuser.

[Galeon]

The only time I have seen general capacitor blow to bits in a fluorescent batten is when the installers put the filling up he wrong way and the mains wiring has to pass the control gear which we know does get hot . Over the years the supply cable melted and went bag . I would have a look at the route of the supply cable in and you may have to swing the fittings around.

I am still amazed how many sparks use a fitting as a wire through to another fitting , not how I was trained to do it.

[John Webb]

Reg 559.6.2 (17th Edition of the IEE Regs BS 7671:2008) allows through wiring but it is only permitted if the luminare is designed for such wiring and the cable is chosen to withstand the appropriate ambient temperature in the fitting.
In addition Reg 522.1 reminds designers of the need to ensure cables can withstand the ambient both in normal operation and in fault conditions.
Mind you, as the original enquiry above comes from Australia, I am not certain to what degree they follow the IEE Regs.

[Galeon]

Reg 559.6.2 (17th Edition of the IEE Regs BS 7671:2008) allows through wiring but it is only permitted if the luminare is designed for such wiring and the cable is chosen to withstand the appropriate ambient temperature in the fitting.
In addition Reg 522.1 reminds designers of the need to ensure cables can withstand the ambient both in normal operation and in fault conditions.
Mind you, as the original enquiry above comes from Australia, I am not certain to what degree they follow the IEE Regs.

I'd go with that John , but its the same old story , when you get out on site its another matter , out of sight out of mind.
I don't know to  much about Australia's way of doing things in the sparky dept , I will leave that to others.

[Big A]

and went bag .

If only they all did.

[Eggcustard]

Very common type of incident, BASF fire, Norwich Library fire for example. Dodgy light components ignition source, fire spread to room by styrene or similar thermoplastic diffuser. Should use a different type of diffuser that chars as opposed to one which ignites and spreads fire to room by formation of burning droplets. Hundreds of serious fires have been caused in this manner across the country.

[Eggcustard]

This is a bit over the top but the principle is the same

 "EIGHTY per cent of schools, hospitals and public buildings are in danger of "raining fires" from electrical lights because the wrong type of diffuser panel has been installed, a trade association claimed yesterday.

The type B diffusers, used to cover recessed lights in suspended ceilings, are almost indistinguishable from the safe type A diffusers.

Both types are usually frosted, but tests conducted at the Warrington fire research centre have shown type B thermoplastics ignite within seconds of an electrical fault and dribble burning drips that spread the blaze on to furniture, carpets and office papers.

Martin Rankle, chairman of the Association of Lighting Diffuser Manufacturers, called for a ban on "type B" thermoplastic diffusers. The association's campaign will be addressed in a Department of Environment consultation paper.

"This is not a minor fire regulation violation, but a danger to many lives," said Mr Rankle. "Within three minutes of the fire starting you get a flash-over because so much heat and smoke is generated. There would be no chance of evacuating a hospital or school."

Several other associations, including the Lighting Industry Federation and the Institute of Building Control, support the campaign for a ban. The flammable diffusers are closely regulated by fire regulations introduced in 1992, but are nevertheless installed because they are cheaper.

A type A diffuser panel costs £4, twice as much as the same size panel made from a type B material. Type A panels also transmit a quarter less light than type B.

Britain's largest fire since the war at the BASF plant at Wilton, Teeside, in October 1995, spread largely because type B light diffusers had been installed, Mr Rankle claimed. Type B diffusers have also been blamed for a £10 million fire that destroyed thousands of historical records at Norwich Library.

Hazel Blears, Labour MP for Salford, said she was "horrified" by the demonstrations she had been shown. "These materials are the difference between life and death," she said. "It is not a parochial matter, but an issue of national concern."

Mrs Blears claimed manufacturers had admitted to her they supplied type B diffusers because of commercial pressures when tendering for public building contracts."

[Chris Houston]

This is a bit over the top but the principle is the same

 "EIGHTY per cent of schools, hospitals and public buildings are in danger of "raining fires" from electrical lights because the wrong type of diffuser panel has been installed, a trade association claimed yesterday.

The type B diffusers, used to cover recessed lights in suspended ceilings, are almost indistinguishable from the safe type A diffusers.

Both types are usually frosted, but tests conducted at the Warrington fire research centre have shown type B thermoplastics ignite within seconds of an electrical fault and dribble burning drips that spread the blaze on to furniture, carpets and office papers.

Martin Rankle, chairman of the Association of Lighting Diffuser Manufacturers, ........."

Can you tell us your source of this material?  I only ask because a google search for "Association of Lighting Diffuser Manufacturers" of their Chairman provides no results.  Which "trade association" made the claims?

[Eggcustard]

Chris, this is from an old Telegraph article,

http://www.telegraph.co.uk/htmlContent.jhtml?html=/archive/1997/10/28/nlite28.html

Martin Rankle had a vested interest as I believe he produced TP(a) diffusers.  However he was absolutely correct and even commissioned tests at Warrington Fire Research to substantiate his claim. There used to be a link on their site but it has since been removed. As a result of his efforts, changes were incorporated into building regs (See ADB B2 P65) limiting areas and situations where lower classes of TP diffusers could be used and indeed banning styrene and the like. This has gone someway to resolving the situation however there are still many hundreds of thousands of low quality diffusers out there, sat squarely under aging, poorly maintained flourescent light fittings, just waiting...

[nearlythere]

This is a bit over the top but the principle is the same

 "EIGHTY per cent of schools, hospitals and public buildings are in danger of "raining fires" from electrical lights because the wrong type of diffuser panel has been installed, a trade association claimed yesterday.

The type B diffusers, used to cover recessed lights in suspended ceilings, are almost indistinguishable from the safe type A diffusers.

Both types are usually frosted, but tests conducted at the Warrington fire research centre have shown type B thermoplastics ignite within seconds of an electrical fault and dribble burning drips that spread the blaze on to furniture, carpets and office papers.

Martin Rankle, chairman of the Association of Lighting Diffuser Manufacturers, called for a ban on "type B" thermoplastic diffusers. The association's campaign will be addressed in a Department of Environment consultation paper.

"This is not a minor fire regulation violation, but a danger to many lives," said Mr Rankle. "Within three minutes of the fire starting you get a flash-over because so much heat and smoke is generated. There would be no chance of evacuating a hospital or school."

Several other associations, including the Lighting Industry Federation and the Institute of Building Control, support the campaign for a ban. The flammable diffusers are closely regulated by fire regulations introduced in 1992, but are nevertheless installed because they are cheaper.

A type A diffuser panel costs £4, twice as much as the same size panel made from a type B material. Type A panels also transmit a quarter less light than type B.

Britain's largest fire since the war at the BASF plant at Wilton, Teeside, in October 1995, spread largely because type B light diffusers had been installed, Mr Rankle claimed. Type B diffusers have also been blamed for a £10 million fire that destroyed thousands of historical records at Norwich Library.

Hazel Blears, Labour MP for Salford, said she was "horrified" by the demonstrations she had been shown. "These materials are the difference between life and death," she said. "It is not a parochial matter, but an issue of national concern."

Mrs Blears claimed manufacturers had admitted to her they supplied type B diffusers because of commercial pressures when tendering for public building contracts."

What are the "1992" regulations you refer to?

[Eggcustard]

Nearly there..I did not write the article. I would imagine the author is referring to the 1991 version of ADB - Fire Safety