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Tom Kunich

"Sorni" wrote in message
...
wrote:
Matt O'Toole wrote:

Gary, it takes *a lot* of UV exposure to break down plastics. We've
all seen styrofoam cups, coolers, and beach toys crumbling from
exposure to the elements, but we forget they've been lying around
outside for decades, and exposed to worse things than UV. Helmets
may get a few hours a day of exposure, a few times a week, if that.
Newer ones have non-structural plastic caps on them, and dyes in the
styrofoam to protect from UV. So the structural styrofoam is well
protected. Basically this is not worth worrying about.

I agree that foam breakdown from direct sunlight is unlikely to be a
problem.

OTOH, I had a person show me her helmet with a cracked "microshell."
The thin vacuum-formed plastic that carried the decorations seemed to
have gotten very brittle. Or perhaps it always was brittle. In any
case, a very minor bump (she dropped the helmet from about three feet)
caused a chunk of that plastic to break off, and it was obvious the
rest was fragile.

I wondered if this was intended to sell helmets. In her case, the
broken-out bit wasn't very conspicuous, but I could see the helmet
looking bad after a few repetitions. Some people might buy a new
helmet just because the first looked ratty. Others might become
convinced the magic had leaked out.

Note, I recall reading an article where a man talked of quitting his
VP position at a consumer products company, in part (he claimed)
because he found out they purposely compounded plastic items to
degrade from UV exposure. Can't say for sure it was true, of course.
He never named the company, and it was just a remark in passing.

"She dropped the helmet from about three feet."

How convenient!

I've seen the same thing. 3' just happens to be the approximate height of
the helmet if you sit it on the handlebars as some riders do or hook it over
the lever.