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Posted By Topic: Asbestos in old wiring?

Apr 05 2019 10:07

I have some old fabric flex like you see on irons etc, there appears to be some powdery fibrous material within it, I have told it may be a mims powder. Was asbestos ever used in this fashion?

Apr 05 2019 11:35

Powder or fibrous?. Unlikely to be both. Asbestos flex has asbestos wrapped around each conductor before being laid up as a 3 core flex. The asbestos is stringy sort off. If you have stripped this you will almost certainly die before you reach 100!
If it is powder more likely to be what was known as "non kink" flex which has ht PVC insulated cores laid up as a 3 core flex(probably with string fillers) and the powder is likely to be chalk used as a processing aid when laying up.

Apr 05 2019 11:49

MIMS insulation is always a powder, and never used in flexes (it's in the name: the second 2 initials are Metal Sheath).
Grey / white fibrous material is almost certainly asbestos. Not just ACM, but the real deal. Used to be common for flexes on irons, and for waterheaters up to art least late 1970s. As apprentice, I had to learn to bind the asbestos onto the cores using sewing cotton, so the cores were heat-protected right up to the terminal. Alternative was fibreglas sleeving, but there's no confusion which is which. There was also asbestos - covered "conduit" wire, where the stuff was woven on around the rubber insulation & looked a lot like VIR but coarser weave. Again found in high-temp appliances, including some water heaters.

No point bothering with a test; It wastes time & costs money; better to just assume it's asbestos.

According to Asbestos regs, not allowed to remove without first giving Worksafe Notice (5 days?), holding a remover's licence, and having an independent overseer. Then proper disposal.

Which is a huge faff & cost, just for a bit of flex (or a fuse, or a switchboard lining, or similar tiny quantity). Basically the regs don't allow for this sort of thing; there's no leeway at all.

Unlike for ACM (eg black-panel switchboards; polite lining, etc); where we're allowed to remove up to 9I think) 10 m2 with no licence, and no faff - just basic precautions.

So what you're NOT allowed to do is to apply procedures for ACM, eg:
1 warn the owner / occupier;
2 put on PPE (mask, gloves, etc);
3 wet out the flex with a spray bottle of water;
4 remove & bag
5 dispose to approved landfill.
6 dry the overspray thoroughly
7 fit new flex; connect & test

What you MUST do is alert owner / occupier; and anyone else who may follow (so best done in writing). Sticky labels are a good idea.


Apr 05 2019 23:13

It was in some very old self ballasted high bays. I didnt want to get my face too close for a good look. But what I saw was enough. I ended up identifying all the lights with the same flex and removing the entire fitting.