Mains voltage downlights

[Nijinski001]

Hi
I have fitted two mains voltage downlights in a friends house on a landing. Above it the insulation is so old it is crumbling in a dry cottage cheesy like consistency. I have brushed the insulation aside for now but I am concerned about fire risk if the insulation is moved in the future and is touching the lights.

What is the risk and what is the right thing to do?

Regards
Kevin

MOD

moved from general diy

 

[ban-all-sheds]

It's not old and crumbling - well, it might be old, but it was like that when it went in - it's loose-fill type, e.g. vermiculite.

1) You'll need permanent barriers to keep it away from the luminaires

2) You may need to build an insulated structure over the luminaires to maintain the u-value of the ceiling.

3) You may need fire hoods over the luminaires to maintain the fire rating of the ceiling.

4) Last, but definitely not least, it is possible that the vermiculite contains asbestos fibres of the most dangerous type.

I have no idea if UK insulation products contain it, but many in the USA do, and I'm pretty sure that our country does not have any vermiculite mines so whatever was sold here was imported from somewhere.

See these:

http://www.epa.gov/asbestos/insulation.html

http://www.vermiculiteatticinsulation.com/

particularly the scary video in the second one.

 

[mapj1]

http://www.defra.gov.uk/environment/airquality/lapc/pgnotes/pdf/minpg3-7.pdf

There are a variety of vermiculite ores which may be obtained from about 65 mines
around the world. Ores used in the UK are currently derived principally from three
major mining operations in South Africa and USA. Vermiculite is imported as a
concentrate of vermiculite flakes within a size range of <1 mm to 8 mm. It is an
inert material. On rapid heating to 900 - 1000oC, vermiculite's interlayer water
expands to form steam. The pressure of this steam evolution forces the silicate
layers apart from one another and the vermiculite flake forms an elongated
concertina-like particle 20 - 30 times its original thickness (The name "vermiculite"
is derived from the Latin word vermicularis, meaning "worm like" on account of the
elongated, twisted and curved columns produced after exfoliation).
3.3 The commercial exfoliation of vermiculite is performed by passing the crude
vermiculite concentrate in a controlled manner through a suitable furnace. The
exfoliation is controlled by a time/temperature relationship, which is critical for the
bulk density and the quality of the product. The exfoliation process usually takes
between 4 and 8 seconds depending on grade, type of furnace and source of
vermiculite, after which the particles are removed from the furnace chamber
through a cyclone or classifier system to collect the product from the hot gas
stream. The classification system not only separates the particles from the hot gas
stream, it also removes excess fines, and allows the product to cool slightly.
3.4 Vermiculite is non-combustible and insoluble in water or organic solvents and its
uses include:
• building products: building boards, plasters, insulation
• industry: insulation shapes, refractory shapes, dispersions, friction linings
• horticulture: growing media, packaging material for bulbs etc.
• agriculture: feedstuff additive, soil conditioner

No mention of asbestos.
http://www.vermiculite.org/hse.htm

Vermiculite dusts, including these fibrous fragment forms, have demonstrated very few if any health effects, other than those that could be expected from any low toxicity silicate. Unlike asbestos, vermiculite has shown very few ill-effects in experimental testing with animals. Chemical testing suggests that it may not stay long enough in the lung to do serious damage.

The general consensus is that the stuff that has been expanded into fluffy stuff from the raw in the UK is safe, but watch for cheap imports.
I'd suggest keeping it out of the fittings with simple vertical plasterboard rectangles tacked to some roof batten noggins nailed between the joists or similar.

 

[ban-all-sheds]

http://www.defra.gov.uk/environment/airquality/lapc/pgnotes/pdf/minpg3-7.pdf
No mention of asbestos.

Nor was there in the advertisements for the US product which the EPA reckon has contaminated up to 35,000,000 US homes...

http://www.vermiculite.org/hse.htm

Vermiculite dusts, including these fibrous fragment forms, have demonstrated very few if any health effects, other than those that could be expected from any low toxicity silicate. Unlike asbestos, vermiculite has shown very few ill-effects in experimental testing with animals. Chemical testing suggests that it may not stay long enough in the lung to do serious damage.

The general consensus is that the stuff that has been expanded into fluffy stuff from the raw in the UK is safe, but watch for cheap imports.
I'd suggest keeping it out of the fittings with simple vertical plasterboard rectangles tacked to some roof batten noggins nailed between the joists or similar.

Vermiculite is not dangerous, and vermiculite per se does not contain any asbestos. There is at least one example of a vermiculite mine also containing asbestos which resulted in the finished product containing asbestos, the dust from which when it was disturbed contained 7 - 12.5 asbestos fibres per cubic centimeter.

Right now I'd rather be wrong in assuming that UK vermiculite insulation might sometimes be contaminated than wrong in assuming it was only ever in the USA and that we have nothing to worry about...

And I really hope I'm wrong.

 

[Adam_151]

And I really hope I'm wrong.

Not as much as I do, as I'm typing this I am sat more-a-less directly below a trapdoor to an attic full of the stuff