The expanded polystyrene inside a helmet needs a fair amount of force to compress it (which is how it helps protect the head). Personally I wouldn't be replacing a helmet just because it was dropped on the floor (from any normal height) but that's just me.
Yes this was precisely what I was wondering about, but on the internet you hear all sorts. I am well aware you get the range of variance of opinions even on this thread but figured everyone would have better rationales to back things up with for some considered views.
The expanded polystyrene inside a helmet needs a fair amount of force to compress it (which is how it helps protect the head). Personally I wouldn't be replacing a helmet just because it was dropped on the floor (from any normal height) but that's just me.