Asbestos and the Equitable Building: What’s all the excitement? Part 2

A short history of asbestos

It is pretty obvious, isn’t it? Once upon a time someone looked at the materials we now call asbestos and said, “What great stuff! Think of all the things we can use it for!” And use it they did.

Three of the great properties of asbestos are 1) flame resistance, 2) steel-like durability, and 3) wonderful insulating properties, and we should also note 4) asbestos can be woven into soft fabric. Every material has its own combination of good and bad properties, and asbestos has some that are quite unique. An article in print called Asbestos Revisited was written by two college professors, James Alleman in civil engineering at Purdue University and Brooke Mossman of the College of Medicine at the University of Vermont. You will find the article on pages 70-75 in Scientific American in July of 1997 in any established library (Des Moines Public Library downtown or Drake to name two).

Let’s examine some minor anecdotal stories of asbestos use. In ancient Persia (now principally Iran and areas both west and east) some tablecloths were woven from asbestos fibers. When it was time to clean them, they were put over fire. Everything on the tablecloth burned off and left it white. Royals and slaves from Persia to Greece had clothing of asbestos. (Imagine the hand-me-downs in those families - grumble, grumble - soft fabrics possessing steel-like durability. “But that was great-great-grandpa Ganath’s. It’s sooo out of style.”)

As a chemist schooled in the 1960s and working since, I have seen a lot of asbestos in lab settings. As we will see in the upcoming Part 3, this was not always a good thing. Most of the common lab equipment using asbestos - but not all - is gone now, replaced by materials considered less hazardous. All schools had 4″ square wire screens with an asbestos center, 8″ square fiberboard asbestos hot pads (that we would break in two accompanied by a little puff of dust), rolls of soft, gray asbestos ribbon that looked a lot like thick burlap, spools of asbestos yarn, and asbestos gloves to handle hot glass. (You can still buy asbestos gloves and find them in labs, but Kevlar has many of the same insulating properties and durability without the dangers.) For the first twenty-five years of my career bottles and cans of chemicals used to arrive packed in a chunky, dusty material called vermiculite, some but not all of which, contained asbestos. Before we laugh too hard about the Persians and Greeks in ancient times, check out this asbestos homeware available in my lifetime.

But people didn’t make their fortunes selling tablecloths and lab gloves. They made their fortunes insulating and fireproofing with asbestos itself and by making products formulated, that is, combined or mixed with asbestos.

Some of the products made with minimally modified asbestos included insulation for steam furnaces, steam engines, and heating pipes, thermal insulation and fireproofing for chimneys and flues, fire blankets, electrical wire insulation, asbestos tape for sealing duct work, and one of the biggest - for insulation in ships for boilers, nuclear reactors, and hot water and steam pipes. In some critical military applications, asbestos is still used. But when you consider this list always keep in mind that asbestos has been largely replaced with safer but sometimes inferior products. Other products that used to be formulated with asbestos include sprayed-on insulation and fireproofing, brake linings and pads, clutch plates, acoustical plaster, ceiling tiles and panels, floor tiles, linoleum, shingles, black jack tar, wallboard, sheetrock, putties, caulking, glues for tile (mastic), siding, popcorn ceiling texture, and lots of other materials. An earlier version of “soft concrete” included asbestos. It was lighter and considered fireproof so was just the ticket for construction, especially roofs. Asbestos of a somewhat different composition is still used in a few types of construction today as noted in Table 6 of the USGS publication. These newer formulations are bonded and nicely contained (unless they are sawed, ground, or finely pulverized by other mechanical processes). Generally I don’t like to posts lists, but this one from Princeton University is nicely qualified. Note where asbestos is likely to be found in buildings constructed before 1981.

If you want to see what some of these asbestos-containing materials look like (because many have survived to this day in older buildings and in homes), try this Web site with great photos of actual aging asbestos materials. These photos are posted by a state-licensed inspector in New York. You can see a few more pictures from a training site at the University of North Texas.

Well, that’s Part 2, a quick tour of the history of asbestos. What great possibilities! The Magic Mineral of the 1939 World’s Fair. I’ll be back later with a little about the discovery of some adverse health effects.

Guest Writer: James G. Lindberg (Jim) is the Purple Wren’s sweetie and is a visiting chemistry professor at Grinnell College and retired from Drake University.

Photo on flickr by J. James Bono

[tags] Iowa, Des Moines, Central Iowa News, Asbestos, Equitable of Iowa[/tags]

Sandy Renshaw is Sandy Renshaw is a self-employed communications consultant. You will also find her blogging at Purple Wren.
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