they say the same thing about car bumpers...if you have any kind of impact to it you're supposed to change out the entire bumper because the damage to the foam. at least on the new cars.
i don't know...could just be another consumerism trick.
maybe send the question in to myth busters...?
I think this is fairly true. A lot of new japanese cars(not sure about domestics, but I'm sure it applies to the newer models) have crumple points, and like you describe, if the foam behind the plastic goes, you're better off replacing the whole bumper. Not sure how much I would heed that though, as it is bloody expensive. Nor am I sure what kind of effect a minor fender bender would have on the whole bumper.
really? u have to replace your helmet after fall? I suppose it have to be a major crash? no?
How often do you replace your helmets then?
I read the warning label on my brand new Giro G10 and it says "After impact, the helmet should be destroyed" or words to that effect. Problem is, the word impact can be interpreted in a bazillion different ways varying in severity. I mean, if I drop it on the pavement, does that mean I have to replace it because its considered an impact? Bottom-line is, the individual has to decide whether or not the impact they experienced was enough to decrease the helmet's effectiveness for the next crash. In my case, I'm not sure if I want to replace it simply because it was only used once
I wouldn't worry too much about it. The helmet's mostly designed to protect you from having your head cracked open, not make each impact feel like you fell on a pillow. You'll be a hell of a lot better, crushed foam or not, if you hit your head on hard ice or a rock than you would otherwise.
I'd keep the helmet even if you bonked it once or twice....
you do not necessarily have to replace a helmet, just coz you dropped it (not unless you dented or cracked the outer shell)... the issue of a compressed foam lining of a helmet, only applies when there was a moving mass inside the helmet in the form of your head.
there is no definitive rule.... which is why manufacturers err on the side of caution.
however, if you do a certain thing, a certain way, that causes you to wallop your head a certain way, you are likely to use the helmet's foam in the same place more than once.
for obvious reasons, its capacity to absorb impact will be less on subsequent occasions than the first and so, with pun intended...just use your head!
Just coz you don't understand it
Doesn't mean it makes no sense!