Hi Guys, A few comments about asbestos. I own and operate an asbestos testing laboratory and have been inspecting buildings and testing materials for asbestos content for 18 years.
Yes, the original heat shields are asbestos containing.
Most older head gaskets, the exhaust manifold to down pipe gaskets, brake linings and clutch linings were asbestos containing.
I believe most of the above are all now non-asbestos.
If you are restoring/repairing a car with the original asbestos items, here are a few tips to keep yourself as safe as possible:
Airborne asbestos fibers are the danger - most materials, left undisturbed will not pose a health threat if they are in good condition and undisturbed simply because in that state they are not likely to release fiber to the air.
Do not grind, sand, shot blast these materials. That is a good way to put fibers in the air.
The safest way to handle/remove is to saturate with 'amended' water - that is water with some dish detergent mixed in. The soap helps break surface tension of the water, helping it to wick/penetrate into the material. Some materials like the heat shields are usually bound in a clay-like binder that will resist water - in this case anything that will penetrate will work - I have used things like WD40 and it works well. Then manually scrape the material off of whatever it's on. The idea behind water (or penetrating oil) is to reduce the airborne fibers. These fibers are extremely small (1/4micron or less - too small to be seen with the naked eye) and are very light weight. Water molecules (or oil) attaches to the fiber giving more weight, dropping them from the air. EPA has estimated that a single fiber released at the ceiling of a room in a home or office could take as long as a week to reach the floor because they will ride on thermals or breezes - again, with the weight of water or other molecules attached, they drop quickly out of the air. The longer they are in the air around you, the more chances you have to inhale them.
All work to scrape/remove should be done with manual scrapers/wire brushes - no electric or air tools. Think: No Dust
Damp wipe to clean - no blowing with compressed air.
You should wear a respirator equipped with HEPA cartridges.
You should have a drop sheet under the work to catch all debris.
Bag all debris in zip-lock bags or some other sealable container, and contact your local Clean Air Agency/Air Pollution Authority for disposal instructions.
Most of all, do this outside if possible - the potential airborne fiber concentrations will be greatly reduced if there is a breeze/good ventilation. You don't want any lingering fibers in your shop to go airborne later. When done wet-wipe all horizontal surfaces where dust could settle to insure you got it all cleaned up.
I am not particularly afraid of asbestos, but I do have a healthy respect for the dangers involved. Most of us in the hobby mode probably won't encounter these materials often enough to cause a problem, but anyone doing restoration for a living should consider that any asbestos fibers you inhale are permanently in your lungs. The more/longer the exposure, the higher the accumulation of fibers in your lungs, and the higher the risk of disease. So, without being paranoid about it, do everything you can to avoid/minimize exposure.
If you have a heat shield you want to save and not replace, I recommend 'encapsulating' with paint - if you are going for concours, you may not be able to encapsulate. For example, I wanted to save the material on a manifold heat shield so I used engine enamel (I get mine from Bill Hersh) which I thinned quite a bit so as to saturate the heat shield material as much/deep as possible, then be very gentile when handling - mine have held up for several years.
Disclaimer - the above roughly comports with most regulations and should help minimize exposure, however, I am not advocating anyone do anything with asbestos containing materials without proper training and protective gear - and checking with OSHA and your local air pollution authority for laws/rules in your area (laws do vary a bit from state to state).
If anyone has more specific questions about handling asbestos, please feel free to PM me and I will help in any way I can.
Dave