A word about certification: certification labels are specific to the country where the helmet is sold. If it’s sold in the US, look for DOT (Department of Transportation) certification. If it’s sold in Europe, look for ECE 22-05 certification, etc. Snell is optional for any manufacturer who wants that stamp of approval.
Certification is also not mandatory. Nobody nowhere is certifying those novelty helmets and skull caps, worn by riders who…honestly…I don’t know why anyone would spend a dime on these things. Here in the US, in states with helmet laws, only about a dozen of them mandate any kind of safety standards. Nice job, legislators. Why even bother?
With the improvements made in DOT standards (Standard #218, a.k.a. FMVSS 218), helmets are safer than ever here in the US, closely paralleling the advanced standards applied in Europe (ECE 22-05). Comparison is difficult, and beyond the scope of this article (and my ability to synthesize sophisticated physics), but in general, helmets are tested to withstand standards of impact to the shell, transmission of force beyond the inner liner, object penetration, and the ability to stay put. Shields on full-face helmets are tested for durability. Chin bars are tested, and modular helmets must withstand the same chin-bar testing as full-faced helmets. All standardized certifications assume that the helmet actually fits you and is properly secured.
What? No Snell certification? The Snell Memorial Foundation is a private, not-for-profit organization who’s purpose in life is to make sure you’re wearing a safe helmet. They set voluntary, rigorous standards, have their own lab and their own technicians, and manufacturers submit individual helmet models for certification as an added selling point to the consumer. Snell certification is not required by any government. Their standards were recently updated (Snell M2010) and closely parallel those set by DOT and ECE 22-05. However, if a helmet was previously certified with the older, M2005 standards, Snell continued to certify it until March 31, 2012, so if you’re relying on Snell certification for purchasing decisions, make sure it’s after that date. (Hint: it won’t say so on the outer Snell sticker; check the label on the inner foam liner).