The History of Asbestos in Electrical Products. 100 Years Ago.

As my weekly Blogs focus on history, I decided that we needed one which discusses the historical use of asbestos in electrical products. Electricians are one of the trades with a long history of exposure to asbestos, whether in the U.K., https://electrical.theiet.org/wiring-matters/years/2020/81-july-2020/asbestos-guidance-for-electricians/, the United States, https://www.ecmag.com/section/safety/asbestos-workplace, or elsewhere.

As mentioned in the articles, electricians are generally exposed either when cutting or removing asbestos-containing construction materials or when working on older equipment such as hot water tanks, furnaces, turbines, and the such. However, the exposure goes a long way back. To show the length of time in which asbestos has been a component of electrical equipment, let’s use the January 1917 Fourth Edition of the Standard Handbook for Electrical Engineers. This book is just over 1900 pages long and incredibly comprehensive on all things then electrical.

Let’s start off with the types of asbestos containing electrical products in use 100 years ago. We have asbestos insulation for magnet wires, asbestos tape, asbestos molded with a binder, asbestos wood or lumber, transite asbestos wood, and ebony asbestos wood.

We then show that mica does not contain asbestos, but some, albeit not all, products sold as “molded mica” does. I suspect that “micabeston” is the trade name which included asbestos based on the below two pages, Section 324 and 312.

Bakelite, based on the below, would have been combined with asbestos at times, but certainly not always. I never knew that Bakelite was invented by Dr. L. H. Baekeland. This was the first plastic made from synthetic components and developed by Baekeland in 1907, marking the beginning of plastics. Baekeland also invented photographic paper and then sold the invention to George Eastman of Eastman Kodak.

Finally we have Vulcabeston and Vulcabeston 201 which used either gum or rubber as a binder to the asbestos so that the fibers could be molded into about any shape. In Section 337 below, stern-asbeston was also a molded material heat-proof up to 200 degrees centigrade.

As you can see, asbestos was an important niche component in the age of electronics and plastics, albeit not as important as pure mica or Bakelite. After 1917, as electricity advanced, the use of asbestos would have also advanced until the late 1990s when it was no longer available for use in electrical components and was eliminated from the National Electric Code insulation table in 1996.

Should you have any questions, please email me at TheAsbestosBlog@gmail.com or leave a comment. Once again, thank you for joining me on the trail of history.