I learned a little something many years ago about helmets used in automotive races versus motorcycle helmets. At first, it might appear the two helmets should meet the same requirements, but according to the Snell Foundation, the tests are actually quite different. Since the threat of fire is minimal with motorcycles, the M-prefix helmets are not required to employ a fire-retardant material in the helmet lining. We referenced the Snell Foundation website (smf.org) and found all kinds of different helmets. The SA, or Special Applications classification, is the designation for auto racing helmets. Testing includes, among other things, a test of the flame-retardant inner liner material. Snell tests numerous other areas besides just how well the helmet deals with impact, including penetration resistance and how well the helmet stays on your head. Since many helmet construction materials degrade over time, Snell recommends a new helmet every five years, but most racing organizations will accept a helmet that has a 10-year-old Snell rating. The current Snell rating is 2005, which means a helmet purchased in 2009 would be accepted in most racing tech inspections until 2015. Other ratings you may see on the tag inside a helmet that won’t work for auto racing include CM (children’s motorsports), K (karting), RS (recreational skiing), and even E (equestrian), which is a different kind of horsepower. I guess this means my favorite SA95 helmet is no longer legal. Bummer.