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Snell & Helmet Standards. Daniel Thomas, M.D. CT Rider Education Program February 7, 2009. Helmet Testing. Impact Test Rig. What Snell Means?. Snell History Snell Standards Snell Testing Snell Certification. Pete Snell. Snell Fatal Cash. Snell Fatal Crash. Snell Fatal Crash.
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Snell & Helmet Standards Daniel Thomas, M.D. CT Rider Education Program February 7, 2009
What Snell Means? • Snell History • Snell Standards • Snell Testing • Snell Certification
Why Standards? Impact Protection is invisible No good way to gauge it directly ...or to complain about disappointment later But Standards may allow riders to gauge impact protection indirectly Standards presume a tremendous number of reasonably identical units Call out tests for representative samples Assume similar performance for the rest
Standards Positives They provide crucial information About important functions Example: What will my helmet do for me in a crash That can’t be determined on the spot Impact protection is invisible Sometimes you can tell when it isn’t there But you can’t tell for sure that it is there
Standards Negatives You’re taking someone’s word That the helmet actually meets the standard The tests were done on selected samples This helmet is identical to the ones tested That the standard has something to do with head protection Standards apply only to new helmets Routine use, crash damage, user mods etc may change everything
Two Standards Types Mandatory - Issued by governments Set minimums for all with the force of law Public Safety Regulation of Public Affairs; i.e.: traffic, commerce etc. Voluntary – Issued by Anybody Sometimes public safety but also other reasons Demonstrate product capabilities Superior capabilities and/or More plausible demonstrations Depends on Market Forces
Two Standards DOT (FMVSS 218) Mandatory Self-certified Manufacturers arrange “reasonable” testing Claim DOT certification for their own products Snell M2005 Voluntary Snell certified Snell does pre-market and in-market testing Manufacturers are bound by contract
Snell Standards • Independent • Most stringent • Updated every 5 years
Why DOT? Manufacturers’ Reasons Mandatory Vulnerability Liability Lawsuits Product recalls Riders’ Reasons It’s difficult to find a good helmet without it
Additional Wrinkle Standards Programs Standards are basically documents Programs are the means by which standards are applied Examples Third party test programs Snell, UL Self-certification DOT, CPSC, ASTM, ANSI
Snell Testing • Standards = Documents • Experience and equipment • Objective and reliable (A2LA)
Why Snell M2005 Riders’ Reasons Demonstrates superior capabilities Helmets tested at higher severities DOT says that Snell indicates a helmet complies with DOT Snell says the helmet does even better More Plausible Demonstration Snell does initial pre-market testing And in-market enforcement testing afterwards
M2005 & Riders #2 • More Plausible Demonstration (continued) • Snell is Independent • No government influence • No manufacturer influence • Snell is not-for-profit • 501C(3 ) Corporation (testing for public safety) • Snell is technically competent • Expert board of directors • Experienced staff • +50 year track record
For Manufacturers Improved Market Appeal Many riders look for Snell Certification Dealers & Distributors want to sell to them
Snell Motorcycle Helmet Standards • Increased impact protection area • Comparison of M2000 and M2005 • New M2010 products in Oct. 2009
Snell Certification • Certification testing - Gate keeping • Random sample testing - Continuing enforcement
Gist Shock Attenuation (Peak G’s etc.) Mostly set by mandatory standards Here in the US that’s DOT More shock attenuation possible requires bigger, heavier helmets Impact Management (hit magnitude limits) Mandatory minimums Snell sets higher, premium levels
M2010 - Why New Standard? • Encourage More Protective Helmets - European riders have no access to more protective helmet due to technical incompatibility. • New Scientific & Medical Findings - Dr. Ching’s finding • New Materials & Technology - Stiffer shell and softer liner
Snell – DOT – ECE 22-05 • Differences depend on helmet size • Medium sizes • Small sizes: XS, S, 54 cm to 57 cm • Largest sizes: XXXL, 62 cm • Comparing • Stiffness – liner property: stiffer → more G’s • Less stiff → less G’s and bigger, heavier helmets • Severity – how big are the test impacts • More severe → bigger hits and bigger, heavier helmets
M2005 vs M2010 for US Riders • Possibly identical in design and manufacturing for sizes medium and larger • Softer liner in sizes small and extra small
Beyond Standards There’s more to helmets than standards Fit Quality Comfort Ventilation, Noise, Ease of Use etc. Looks Cost Snell claims no special knowledge of these and neither does DOT Riders can tell us better than we can tell them
The Helmet Took Some Punishment • OOPS! • Dropping an empty helmet is not likely to affect protective performance • But there may be some cosmetic scars as a result • Crash • If a helmet with a head inside takes a solid thump, protective capability may be degraded • But there may be few or no outward signs
Damaged Helmets • Scuffed Paint • Cracked Shell • Damaged Foam
Cosmetic Damage • Chips • Dings • Minor Scratches • “Freckles” across the brow and chin bar, especially open car and motorcycle use • Odor
Impact Damage • On the Shell • Broad patterns of parallel scratches • Broad patterns of fine cracks in the paint • Radial and/or Concentric • Splits and/or discontinuities in the shell • Delamination • In the Impact Liner (EPS) • Dents and depressions • Areas of “Sponginess”
Caveats • Some shells don’t show damage • “oil-canning” • Hidden delamination • Most liner damage may be hidden between the inner surface of the shell and the outer surface of the liner
The Helmet Got Old • Snell recommends owners routinely replace headgear after no more than 5 years of use. • We also urge that rulebooks allow the current and immediately previous Snell certification. • The manufacture date label may not be a fair way to judge helmet age.
