There are basically two classes of helmets to compare:
CPSC (Consumer Product Safety Commission) based on safety regulations impact standards.
All other skate / bike helmets (which still protect your head) without this certification are made for style and comfort.
Here are some snapshots of the Protec brand skate helmet interiors. CPSC has a thick hard interior shell that is glued to the shell of the helmet. They come with extra fit liners that attach with Velcro whereas the other is a shell with even thicker but softer padding. Which one to use is up to you. From what we have see, they are matched in popularity.
CPSC Helmet Construction
Standard Helmet Construction
Hardhats by law are technically NOT helmets and are NOT certified as such. Hard hats do not meet official California Helmet certification (CPSC) for youths under 18 in California.
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