Asbestos - What It Is And How It's Used
In this, and a series of articles that will follow, we will
cover asbestos, what it is, how it's made, what it's used for,
the health risks of asbestos exposure and how to protect
yourself against asbestos.
Asbestos isn't actually one thing. It is a name given to a group
of minerals. These minerals occur naturally in bundles of fibers
that can be separated into thin threads. These fibers are
completely resistant to heat and any kind of chemical and do not
conduct electricity. Because of these attributes asbestos is has
been used in many industries.
There are basically four types of asbestos that are used.
1. Chrysotile, or white asbestos 2. Crocidolite, or blue
asbestos 3. Amosite, which usually has brown fibers 4.
Anthophyllite, which usually has gray fibers
The problem with asbestos fibers is that they tend to break very
easily and the dust made up of these fibers floats into the air
and gets on our clothes and in our lungs. When this happens
serious health problems can occur.
Asbestos was first mined and commercially used in the United
States in the late 1800s. During the second world war its use
increased dramatically. Since then it has been used in many
industries. To give some examples, the building and construction
industry uses it to strengthen cement and plastics. They also
use it for insulation, fireproofing and sound absorption. The
shipbuilding industry uses asbestos to insulate boilers, steam
pipes and hot water pipes. The automobile industry uses it in
its brake shoes and clutch pads. There are over 5000 products
that contain asbestos including sewage piping, roofing and
siding, electric switchboards, table pads, heat protective mats,
heat resistant blankets and curtains, paints, adhesives,
caulking, and the list goes on and on.
But when the dangers of asbestos became known in the 1970s the
U.S. Consumer Product Safety Commission (CPSC) banned the use of
asbestos in wallboard patching compounds and gas fireplaces
because the asbestos fibers in these products could be released
into the air from its use. Also during that time, asbestos was
removed from electric hair dryers. In 1989 the EPA finally
banned all new uses of asbestos. Uses prior to 1989, however,
are still allowed. Since that time, the EPA has established
regulations that require school systems to inspect for asbestos
that has been damaged in order to eliminate, or at least reduce,
the exposure to students and faculty, by removing the damaged
areas.
In the year 2000 the EPA concluded that the current risk to
children from asbestos in schools was very low, however, it was
agreed that their products would have to be reformulated within
a year. By August of that same year products were being made
that greatly reduced the amount of dust that was released during
use. The amount of metric tons of asbestos generated in a year
dropped from 719,000 metric tons in 1973 to only 9000 metric
tons by the year 2000.
In the next instalment we'll go over the health risks from
exposure to asbestos.