This is my advice on dealing with asbestos wiring, not a specific safety standard but hopefully a common sense solution for having to deal with it. A few times a year I am given fixtures to re-wire for a client that has it, much less early on in my career found a brand new spool of it and proceeded to re-wire as many fixtures as I could with it given the whips before this were in much worse condition yet and there was no budget or knowledge on my part. This in addition to doing some catacomb exploration at the high school where the silvery fibers were in the air all about me, or even taking a crap right next to a very damaged asbestos lined water pipe in a theater where it had lots of asbestos whips I was not allowed to fix with new wiring, plus a fire curtain of it that every time it moved had some amount of it’s fibers in the air. This fire curtain was approved and mandated for use as safe but children were banned officially from the stage due to it and the pipes. Not that the rule was followed. Stupidity all around but reality. Cancer from asbestos shows up years later and cannot be really forecasted on exposure level like lead. At some point I might get it, or given my current very real precautions in dealing with it, and having made it thru the 10 year danger zone, I did get lucky (crossed fingers still) because it was commonly about me.
Places that have less money for staffing and care of their equipment will when using older equipment often turn a blind eye to it's existence or not recognize the potential danger of it’s continued use. Many won’t even link the knowledge of asbestos being bad with that’s what is on the wiring they are using. There is one form of heat wire much similar in look to asbestos that is not, but it is much more rare than one of the forms of asbestos heat resistant wire in general for use.
As with past posts on the subject of asbestos a search would reveal, it's not good to see or healthy to be around, limited exposure and breathing it in is the key while phasing it out. Used to be I was more worried about such asbestos having problems with moisture, flaking off and exposing conductors. In general, asbestos whips that also have the conductors exposed in areas the insulation flaked off are still more dangerous than something that looks as if it’s braided, but all is not something in magnitude upon seeing or having to use to once in a while to be overtly hugely concerned about. Something in your thoughts but not something to give you nightmares since there is little you can do about it. Remember that it’s not the cords, especially those that are in good condition to be worried about, it’s the fibers that flake off that you breathe in.
What happens to these fibers from the cord once they flake off? That’s the real scary thing about asbestos. For me it’s less the whip I can control my exposure to, it’s more the in general dust in the air at the theater as I walk in this asbestos is mixed in with as I walk in the door, or most especially that of which is in a more compressed space of a catwalk as I stir up a wind in walking around on it. This given some fibers will have already fallen off into the audience.
Are you getting some kind of feel for the scope of the problem here in it being specific to the whip as localized, but even the whip being far less to worry about than what’s already flaked off one week ago to 60 years ago still existing in the dust at the theater? Even if you replace all the whips, pipes etc. in the theater, unless you vacuum up all the dust in the entire space, it’s still in existence. Those outraged by my less than worry about the whip thus know why I’m not as much about it both by the volume of the insulation on the cord and the price for doing business due to the history of the space. In wiring a new DMXline to the dimmers and climbing the curve of the ceiling over the audience, I saw a 1926 tin candle still hanging in it’s position where some person constructing the building had left it while no doubt tie wiring the support to lath in the ceiling. This amongst many other found items or trash left behind in the theatre building. Cancer from asbestos is linked, but cancer in general or your percentage chance of getting it from fibers in the air while they might be more pronounced in a older theater even if it’s all gone, is there as a element that will never go away. Work in a theater that pre-dates say 1980 and there will still be fibers of it in the theater’s dust. Given this, and while you still are taking a chance, it’s still a small chance in even going to see a show as audience member by way of exposure level as opposed to chance.
Be just as concerned about the safety of the lights you are attempting to use in their own safety given asbestos heat wire has not been on the market for at least 20 years now thus the fixtures could not have had a maintenance call since than. Getting shocked and falling, either can also cause death.
All it takes is a few microns of it's fibers in your lungs and you have a chance of getting cancer.
This said, the amount of asbestos wrapping around a conductor is by far less than those covering a pipe, ceiling or even fire curtain. In a volume type of way the chances of breathing in some of it are by far less - on the theory level in general by way of volume of the space you are working than that of a pipe hung under the stage that flakes off a little each time someone stomps on the stage. You do want to avoid cords that have it's insulation "fluffy" and in general easily flaking off. Those with some form of varnish coating still on them and still compact in not easily flaking off as you touch the cord are much more safe to deal with on the grand scale. Need to be replaced especially if they seem in some way rotted, but still safer in that the fibers are less likely to flake off.
Asbestos is not safe to be around in general - and if possible I would consider it a favor to all others you are around if you ask than cut the whip off fixtures wired with it when not absolutely necessary at the time to use. Ask in presenting the problem, perhaps in you recognizing the fault, others have not before you realized or spoken of it. Given this necessity to work with the equipment, wear a mask while in a confined space such as a cat walk, and otherwise as a general theory when in a more open area, be aware of holding your breath when moving the cord if not put your nose as far as possible from it as possible in a simplistic but reality type of way. Best you can do at times will be to be aware of the danger. It should not be understood as an exposure level type of thing because all it takes is a micron or two, but in reality anywhere you visit will potentially have some form of this presence on the grand scale. Such research into asbestos was not because lighting technicians showed up above others as most likely to get cancer from it, instead, most likely the studies into it was done due to the people installing the asbestos industrially on pipes, floor tiles and other things. Your mom and pop might have just as much exposure to it in walking into a construction zone over the years.
Cut with approval the whips off the lights having it when possible and if not approved even after a immediate need, walk from the place in stating your differences due to the health safety of the place as needed and as even necessary in presenting these issues to the top. But for the most part, the damage has already been done short of putting on a mask upon entering a stage just about anywhere.
In addition to this, so also is latex for women, fiberglass in being under study for more than just causing you to itch, dust and many other things including many of the insulation flame proofing materials that followed asbestos in the 80's understudy, all having different effects on a body. Use casien paint - smelly and smelling like salminila and it probably is not wise to eat luch without seriously cleaning your hands.
I hope it helps, asbestos is not something to leave in existence, but short of getting cleaned up what’s already fallen off, there is not much you can do beyond due care in exposure to it. Some years ago when I was a Cub Scout, we had a Scout Master that had a jar of mercury. He let us play with drops of it in the palm of our hand. Times are much more safe now and do take due caution, but even today if it’s your time it’s your time.
While I have had a lot of exposure to it over the years, these statements are not intended to portray any sense of stupidly thinking that it's safe to be around. It is not. Instead, because it is around, caution should be taken when dealing with it, but also a realization that the whip when not moved or wind especially blowing on it is of less danger than perhaps at times just the dust near the side door that gets sturred up as you enter, or especially the dust in the cat walks.
I can think of two or three grades of asbestoswhip. One is tightly compacted, I think had a loose thread keeping the braid in place and did not flake easily. It on the other hand had constant problems with rot. Others very fluffy in nature let fibers float in the wind when ever they were moved. Another similar to the secondary while fluffy was a little less so thus another type or just having had the main part of it's insulation already come off into the general dust of the theater.
Asbestos is not good and needs to go away, but it's even more dangerous effects will always be around.
I don't overly worry about these effects of exposure given there is nothing I can do about it at this point beyond taking precautions when directly exposed to it.
Mind you, exposure to Hg some thirty years ago is all but irrelevant now but as you have correctly pointed out mesothelioma (the cancer you get from asbestos exposure) takes decades to develop and it is believed that all it takes is one fiber to adhere to the lung.
Smoking as well as exposure to asbestos dramatically increases your risk of developing lung cancer.
Here in Western Australia, we had a (now famous) asbestos mining community from which pictures were taken showing children playing in piles of blue asbestos dust in the 60’s. As with such things, the risks were not known until many years later. Too late for some entire communities. In addition to the miners, their wives/mothers were also exposed when doing the laundry and thus too, many have subsequently developed mesothelioma, for which there is no cure and currently a very poor prognosis.
In general, it is a good policy to wear a filtered face mask when working in an environment where there is a lot of dust or air borne particles. Think of it this way, our lungs were designed for the exchange of gases, not particles of dust or other airborne matter. Any foreign material that enters the lungs initiates an inflammatory response and certain cells in the lungs attempt to breakdown and remove the material. In some instances however, it is unable to do this, which can then place the lung at risk of developing a variety of diseases including cancer. Gas from welding and soldering are also toxic to some degree and gases offer another risk as well as they can pass directly into our blood. This is how those who sniff solvents etc get off and the reason that smoking has systemic effects.
How many times have you used a spray pack to paint something and later blown your nose and noticed that the tissue, hanky, your finger is now stained the same colour as the paint? What you are seeing is what your respiratory tract is able to catch and expel from your lungs but it cannot stop all of it. Not to mention the headache you get from the fumes.
Smoking actually reduces the ability of the respiratory tract to filter and remove the crap that you breath in – something to think about before lighting up?
As Ship says, asbestos hasn't been used for 20 years or more, but there is a good chance that many of us will come across some when we decide to restore an old anchor or maintain a lantern that has been negelected for a number of years.
Does anyone have some pictures of asbestos wiring to help everyone recognise it instantly when we encounter it?
This is from various years of the NEC dating back to the 1940's.
AF- Asbestos 302°F. Fixturewire,18-10 Awg. Heat resistant,With some moisture resistant types.300v. Max.
AL- Impregnated Asbestos Under 300v. 257°F., Dry only.
AVA, AVB, & AVLAsbestos and Varnished Cambric, 194-230°F., Dry with AVL wet.
FEPB- Same as FeP, but with glass braid or Asbestos type outer covering. 392°F. Dry only.
HPD- Heater Cord 18-12 Awg., 2 to 4 conductors. Dry Use Only. Thermoset or Thermoset with Asbestos covered wires instead of cotton, but similar to type C. Covered with cotton or Rayon. Not Hard usage.
SA- Silicone Rubber or Silicone Asbestos, 194°F. For dry and Damp Areas. Silicone Rubber insulation with Glass or other Braided covering. (392°F. Special Applications)
TA- Thermoplastic and Asbestos, 194°F., Switchboard use only.
Disreguard the -A in SOW cable, Not sure what the -A means but it's not part of the description of the cord necessary for our purposes.
S- Hard Service Cord with two or more stranded conductors 18 - 2 Awg. with a serving of woven cotton between the copper and the Thermoset insulation. Jute or other “fillers” are twisted together with the conductors to make a round assembly. Outer jacket of high quality rubber or modern Thermoset. For Portable or Pendant, damp locations. Extra Hard Use. Stage and Garage Use.
SO- Cord, same as S cord, thermoset insulation with an oil resistant jacket of neoprene or similar material thermoset. Rated for stage and garage use.
SOW - Same as above but water resistant
SOOW - Same as above but oil resistant inner and outer conductor coverings.