Texas Helmet Safety Standards: An inner liner of one-inch-thick, firm polystyrene foam. If the inner liner is not visible, then you should be able to feel its thickness. The helmet should have a sturdy chinstrap secured with strong rivets. It should weigh around three pounds. Most helmets that do not meet FMVSS No. 218 weigh around one pound. There should be nothing protruding more than two-tenths of an inch from the surface of the helmet. Most non-compliant helmets are smaller, lighter, and thinner than what DOT requires. Be aware that an apparent DOT sticker located on the back of the helmet does not necessarily guarantee DOT approval. Some novelty sellers buy counterfeit DOT stickers to place on helmets. Be sure to consider the helmetâs weight and foam-thickness rather than relying upon a DOT sticker. Other Indicators of Safety: Two other labels you may see inside a helmet are from Snell or ANSI â both of which are private, non-profit organizations. These labels also indicate the helmet meets FMVSS No. 218. Another indication that a helmet is compliant with DOT standards is a manufacturerâs label that indicates the model, size, manufacture date, and what the helmet is made of. DOT-approved helmets are required to have this label.