10. If the BSI standard is so good, why not simply build the helmet to meet both the BSI 6658 Type A and Snell 2000 standard as well, and avoid any confusion?
a. As mentioned above, the major deviation between the two standards in found in the second drop height. This requirement forces the manufacturer to build a much stiffer outer shell to perform well in the Snell 2000 second drop impact tests. This stiffer shell requirement may also prevent the helmet from passing the BSI 6658 Type A standard, by not allowing the helmet to start absorbing energy until a much higher threshold. By not allowing the helmet to begin managing energy at the typical speeds and energies a rider is most likely to experience, the Snell 2000 is counter intuitive to the BSI 6658 Type A.
11. What is the essential difference between the mandatory DOT standard and the voluntary standards such as Snell and BSI 6658 Type A?
a. While there are several significant differences between the DOT standard and other voluntary standards, the key difference has to do with something called "Dwell Time". Dwell Time is best expressed as the duration in time above a pre-determined deceleration that the head, or brain is experiencing during impact. The DOT specification calls out a maximum allowable deceleration of 400g from a drop height of 1.8 meters with sustained energies above 200g to not exceed 2 milliseconds and 4 milliseconds above 150g. This energy duration, or dwell time, is an important consideration in preventing brain injuries at the anticipated energies a rider might experience in a fall. Both BSI 6658 Type A and Snell 2000 require a maximum deceleration of 300g, (a 100 G force reduction) but have no "dwell time" component built into the standard. However, it is important to note that while neither BSI Type A, nor Snell 2000 have a dwell time component, each standard MUST pass the DOT 218 dwell time requirement to be considered legal for street use in the USA.
12. How well do Snell and BSI Type A helmets comply with this Dwell Time requirement?
a. Suomy helmets built to the BSI 6658 Type A standard perform extremely well in the Dwell Time test, while helmets built to Snell 2000 may not perform as well due to the stiffer outer shell the standard mandates. Due to Snell's post public release testing and for reasons previously mentioned above, some helmets manufactured to the Snell standard may not pass the DOT compliance test (Reference . National Highway Traffic Safety Administration .
DOT Performance Compliance Test results:
http://www.nhtsa.dot.gov/cars/testin...18/index.html). However, with the BSI pre factory release batch testing, helping to ensure compliance, a DOT failure is highly unlikely.
13. I understand that BSI 6658 Type A and Snell M2000 are the only nationally recognized racing standards in the USA. But I don't race. Is a Snell or BSI Type A certified helmet safer than a DOT certified helmet for my street riding?
a. While the Snell standard is recognized by the general public as superior to DOT for the racing community, many experts believe that a helmet manufactured to the DOT standard is actually safer for street riding than a helmet manufactured specifically to the Snell standard. At first Glance this might seem illogical, after all if Snell is good enough for racers than it must be better for street riders, right? This is not always the case! With the Median motorcycle street accident being just 29.8 MPH prior to impact, (Source . The HURT Report Summary, Line #15 -
http://www.cs.wisc.edu/~john/vfr/hurt.html University Of Wisconsin), and many impacts being a glancing blow to the side of the head, a typical Snell certified helmet might not experience ENOUGH energy to properly dissipate the energy being transmitted to the head (this is a result of the heavier and stiffer outer shell that the higher Snell second drop on a hemi anvil requires). This may result in unnecessary concussion or head injury. Suomy helmets built to the demanding BSI Type A standard have built in features that provide for extremely favorable DOT test performance as well as the more demanding requirements of the BSI Type A standard, and each Suomy BSI certified helmet is batch tested for performance compliance prior to public release to help ensure that your Suomy BSI 6658 Type A approved helmet passes both the BSI test as well as the mandatory DOT tests.
1. You mention that many helmet impacts are a "glancing blow" to the side of the head. How do BSI and Snell test for this important and common type of impact?
a. The BSI 6658 Type A utilizes two unique impact energy management tests to ensure the helmet will perform when asked to. In the first test the helmet is impacted against a bar anvil to assess projections from the general shape of the shell and in the second test the helmet is impacted against an abrasive pad. These tests are utilized to ensure that the helmet will not have any design features that could catch and twist the rider.s neck. Interestingly, Snell does not test for either of these Oblique Impacts.
2. When asked if lower priced Snell helmets are as safe as their more expensive counterparts, Ed Becker of Snell responded, "My feeling is they are", (Source - Laurie Watanabe, Dealer News January 2001 article "Snell Game"). Many helmet manufacturers disagree and state that their premium helmets perform much better at deceleration below 300g than the less expensive counterparts. They are demanding a tiered performance certification depending on how well the helmets do at managing energy. My question is what is Suomy's response to these claims?
a. In testing for deceleration, the key test to helmet performance, the results are clear and irrefutable. We are unhappy that something so precise as helmet deceleration performance, analysis and the organization that has built its reputation on analytical examination has diluted the answer of this important and direct question down to a "feeling". But it goes farther. In addition to this legitimate concern, many premium manufacturers complain that high volume low priced helmets are not sampled (post public release) to the same percentages for performance compliance than the higher quality, lower volume premium helmets. It has been suggested that if Snell enforced and tested a standard percentage of helmets produced by each manufacturer many of these so-called Snell certified helmets would not be able to maintain the standard. (Source: Arthur Domagala, Motorcycle Industry Magazine, December 2002 Issue article "Are All Snell Helmets Created Equal"). All BSI certified helmets are all pre public release batch certified to the same percentage for each batch size ensuring equality for all manufacturers seeking BSI 6658 Type A certification.
3. You've made a strong case for BSI for the USA market. Why is Suomy the only major brand to import their helmets to this exacting and equitable standard?
a. This is a very good question. Maybe because Suomy is a pioneer in helmet development and rider safety and not afraid to take the better, if not beaten path. Finally, our case is simple; we have available to us a standard that complies with the mandatory DOT performance requirements, is approved by every major motorcycle racing organization, offers better quality controls and we believe a statistically safer helmet for all riders, whether it by for the street or track. Knowing this, how could we NOT take this option? Maybe you should ask your favorite manufacturer why their helmets are not produced to the BSI 6658 Type A standard.
For further reading for insights into helmet standards and their perceptions in the marketplace, please see the following articles; Laurie Watanabe, Dealer News January 2001 article "Snell Game" - Kris Slawinski, Motorcycle Product News, March 2001 article "Snell : Gold Standard or Old Standard" . Marc Cook, Motorcyclist Magazine June 2002 article "The Real World: Six Critical Facts About Helmets" - Lance Oliver, American Motorcyclist June 2002 article "Hat Tricks" - Arthur Domagala, Motorcycle Industry Magazine, December 2002 Issue article "Are All Snell Helmets Created Equal?".
See also the following references:
BSI - .
http://www.bsi-global.com/index.xalter
Snell Memorial Foundation -
http://www.smf.org/
National Highway Traffic Safety Administration . DOT Performance Compliance Test results:
http://www.nhtsa.dot.gov/cars/testin...218/index.html
The HURT Report Summary -
www.cs.wisc.edu/~john/vfr/hurt.html
Head Protection Research laboratory -
http://www.hprl.org
Re: "A New Helmet Standard" CYCLE WORLD MAGAZINE October 2002 page 34
ΠΡΟΔΙΑΓΡΑΦΕΣ ΑΣΦΑΛΕΙΑΣ ΠΡΟΣΤΑΤΕΥΤΙΚΟΥ ΕΞΟΠΛΙΣΜΟΥ
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