jmwagner wrote:
>
> I thought they stopped asbestos in brake linings... at least, in all the pads
>that
> are standard equipment, etc... (i.e. not custom racing pads, etc.) Am I
>wrong?
> Nevertheless... asbestos or not asbestos... the warning seems wise... no
>matter
> what it is, particulate matter is not a good thing to breath.
I write maintenance manuals for a living, for commercial heavy-duty
equipment, and I put a warning into every book about both asbestos-based
and organic-based brake material. First, that asbestos fibers have been
shown to be harmful to health, and that the health effects of
substituted organic brake materials have not been established, and
should be treated as harmful.
Moreover, the previous suggestion that aerosol-delivered brake cleaners
solve the problem has been found to be less than effective. The blast of
propellant from the can raises almost as much dust as compressed air. If
one thinks brake cleaner is necessary, the entire brake area should be
wetted with water first (not under pressure), and then brake cleaner can
be applied. This will significantly reduce the amount of brake dust
raised.
This is one of those areas which can be taken to extremes, I admit. I
think, personally, that some people are most susceptible to the effects
of inorganic fibers and suffer from that exposure, and others are not.
Nevertheless, who of us knows whom is susceptible? Common sense should
apply. As for the suggestion that linings have been changed in the last
few years, it's worth mentioning that many here are working on older
cars of which the maintenance history is not well-documented. Many
people may well be working on cars which have not had any brake
maintenance since prior to the change in brake linings.
It's also worth mentioning that ordinary masks (the cotton and paper
fiber variety held in place by an elastic strap) do not trap the
particles which cause the most damage. Some health physics research done
in the early `80s established the following: particles above 1 micron in
diameter do not attach to lung tissue permanently, and are eventually
expelled. Particles below 0.8 micron have too little surface area to
allow them to stick to lung tissue. Particles in the range of 0.8-1.0
micron in diameter do lodge in the lungs and remain attached. Because of
the physical nature of inorganic fibers, the suggestion in the
scientific literature is that they act as an irritant to lung tissue,
and that the continual irritation eventually causes cell mutations which
lead to mesothelioma and related cancers, and to the scar tissue which
gradually impairs lung function.
Given that, I still think lung impairment, like most other physical
abuse, is cumulative. It's still worth mentioning that there are still
those cases in which limited exposure has caused significant long-term
trauma. Be sensible about brake work, folks. There's also considerable
suggestion in the scientific literature that children exposed to
asbestos dust in the first eight years of life have more pronounced
health effects from exposure than do adults. Keep the kids back a bit
when you're explaining how to fix brakes.
Cheers.
--
My other Triumph runs, but....
|