Most states that require helmets mandate DOT (Department of Transportation) standards. These standards are published by the U.S. federal government and have been around since 1970. Snell is an independent non-profit organization that has been testing helmets since 1959. Unlike DOT, the Snell standard is not mandatory. Helmet manufacturers may choose to submit helmets to Snell for testing - if they pass, they get to put a Snell certification label on their helmet.

A brief history of Snell: William Pete Snell was an avid amateur automobile road racer. He competed in many events and at one SCCA sanctioned race in 1956, he was involved in a single vehicle rollover accident. Doctors determined that the accident was survivable in all other ways, but William died as a result of the head injuries he sustained. He was wearing a Cromwell helmet; one of the better ones available in those days. But the cork, fiberboard and leather construction were simply insufficient to protect him. Dr. George Snivley was a friend of the family and also an avid car racer. He undertook what became a life-long project to study helmets and attempt to quantify their performance through scientific testing.

Our tour guides for the morning were Ed Becker (Executive Director, on left), Hung Zhang (Director of Education, on right) and Allen Harris (Testing Technician, center).

Ed gave us a brief synopsis of why and how the Snell Memorial Foundation came into existence and then talked a bit about the standards. What is important to the survivability of an accident is to limit the force applied to the brain if there is an impact. A Wayne State University study provided some measurements based on cadaver brains that suggested that the onset of brain damage might occur around 400 Gs and forces in excess of 600Gs would likely result in a fatality. Likewise, a study that compared helmeted and un-helmeted riders in accidents where both victims were riding the same motorcycle (driver and passenger - one with helmet and one without) from 1972-1987 concluded that riders were 2 times more likely to survive if wearing a helmet. The scientists noted that the odds of survival increasing dramatically towards the end of the experiment. They attributed this improved survivability to the improved performance of more modern helmets!

Let the Helmet Bashing begin!

OK, this is what we all came for - to watch helmets get bashed, mashed, crunched and otherwise tested to completion! A copy of the Snell M2000 standard can be found at http://www.smf.org/pdf/m2000std.pdf

First, the helmet is marked for the areas where impacts can be administered - this corresponds roughly to the top half of the head with somewhat lower being allowed in the back. Allen is shown here using a computerized jig to mark out the helmet. He also measures visual range at this time - all helmets must have 105 degrees of lateral visibility both left and right as well as 7 degrees up and 35 degrees down from horizontal. This ensures that the helmet will not interfere with the peripheral vision of the wearer.

Chin Bar Deflection Test: This was the first test we saw demonstrated. A helmet was strapped into the test unit and a 5 kg weight (11 lbs) was dropped on the chin bar. The chin bar must deflect no more than 60 mm from an impact of 3.5 m/sec. The helmet did just fine and we were quickly on our way to the next test.

Chin Bar Deflection Test

Dynamic Test of Retention System: After strapping the helmet on the headform, the chinstrap is "pre-stretched" with a weight and then a second weight is dropped to administer a quick, sharp blow to the chinstrap.

Dynamic Test of Retention System

The strap must not come undone, break or stretch by more than 30 mm. Our test helmet showed a deflection of 32 mm - it failed the test!

Positional Stability (Roll-off) Test: Next, a helmet was fastened to another headform and suspended so that a weight on the end of a strap could administer a sharp blow to see if the helmet would get pulled off the headform. A helmet won't do you any good if it comes off during an accident! Good news, this helmet passed this test!

Positional Stability Test

Removability Test: This final remaining test wasn't demonstrated; however, armed with only a pair of shears, simple-edged tools and a flat blade screwdriver, a technician must be able to remove a helmet that is fastened on a headform. The trick is, they can't use the buckle or any other helmet mechanism. The operation must be able to be completed in less than 30 seconds - this ensures that a helmet can be removed from an accident victim easily even if the retention system cannot be operated.

All in all, a very interesting tour! So just how does a manufacturer get a helmet certified and just how much does Snell make on testing? The first step is to submit 5 samples for certification testing. Snell charges $940 and tests 4 of the helmets (one is kept as an "archive" sample). If there are any failures, then it's back to the drawing board for the manufacturer.

Once the helmet passes certification, the manufacturer can label their helmets with a Snell sticker as long as they comply with continued random sample testing. Each year, Snell goes out and buys sample helmets from random dealers. Snell charges $120 per helmet (in addition to being reimbursed for purchase price) to test these helmets. They are subjected to all of the same certification tests, however testing is done to 90% of the original standards. If a helmet fails any of the tests, three more samples are bought and tested. If any of those three fail in the same way as the first, then the certification can be pulled for the helmet.

Certification labels have serial numbers and so each helmet gets a unique label. The labels are sold to the manufacturer for 60 cents each. Snell does receive some donations from private individuals and also applies for some government grants.

What did we learn? Snell takes their testing seriously. The tests are both sophisticated and at the same time simple. Is there room for improvement in the world of helmet technology? Ed stressed that he thought more lives could be saved if helmets could be made to protect the wearer better.

After our tour, we all went to a local restaurant and had a great lunch and got to chat some about what we had heard and seen. We wish to thank Snell for their hospitality and especially those who took time out of their weekend to come in and show us what they do at this unique place. It was a very interesting, informative and educational visit!