The Helmet Update
Volume 31, #3, May 7, 2013
All issues index
Bicycling helmet article misses the mark
Bicycling magazine's June 2013 issue has a helmet article titled "Senseless" with a summary: "Bicycle helmets do
an outstanding job of keeping our skulls intact in a major crash. But they do almost nothing to prevent concussions and
other significant brain injuries--and the very government agency created to protect us is part of the problem. The time
has come to demand something safer."
"Almost nothing" to prevent concussion does not reflect reality. Today's helmets do help in concussive impacts, but are
not the whole concussion story.
We take issue with the primary conclusion of the article. It reads as if MIPS slip-plane technology helmets were the only
current helmets that offer any concussion protection. (They have an extra shell inside that can slip about 5mm in an
impact.) The last pages are all about MIPS, with only the patent-holder's data to support performance claims. At the end,
the author reports that he has bought four MIPS helmets for his own family, a powerful endorsement. He says "You can
pretend to protect your brain, or you can spend more money and get closer to actually doing it."
Nowhere does the article mention the key flaw in the MIPS argument: in the real world, bicycle helmets are so loosely
coupled with the head that a slip-plane inside the helmet structure does not add significant sideways movement in an
impact. The helmet moves anyway, unless it is constrained in a lab test. We told the author that, and pointed to it on
our web page, but he chose to ignore it and quote us and others on less basic points about MIPS as if we thought those
minor points were the important ones. That is highly misleading to the reader.
There is no real-world data showing that a helmet with a slip-plane is better at preventing concussions. The helmet you
wear now has a slip-plane--your head--even if you bought it for $10 at K-Mart. You can prove that by jamming your helmet
down as hard as you can on your head, then seeing how easily it still moves.
The article explains why MIPS was unable to license their product with the patent-holder's assertion that helmet
manufacturers rejected the MIPS technology because they did not need it to pass helmet standards and had no regard for
the concussion performance of their products. We find that ludicrous.
Beyond those elements, the article has some merit. It points out the success of current helmets in mitigating
catastrophic injury. It speculates that helmet use has helped to lower cyclists' deaths. There is good coverage of the
obstacles to improving the CPSC bicycle helmet standard.
On the down side, the article states that "the concussion rate among bicycle riders has grown faster than the sport,"
without addressing how fast "the sport" has grown, or the millions of miles of bike rider exposure in commuting and
utility cycling that has little to do with "the sport" and for which no US statistics are gathered. The author bemoans
how innovative liner materials are eliminated by CPSC's "extreme" test environments, but does not understand why those
tests are more important to the consumer than permitting innovative cardboard helmet liners. CPSC has no rotational
energy test, but neither does any other bicycle helmet standard in the world.
For the record, there are some other minor errors:
- Your skull does not "absorb energy" from an impact.
- There is no statistical proof that half of all riders were wearing helmets by 1999 and that more riders wear them
now.
- Helmet standards pioneer George Snively did not invent helmet testing in his garage.
- Pete Snell's helmet was made of pith, not leather.
- The CPSC standard did not sweep "the garbage off the shelves" in 1999, the ANSI standard had done that in 1984.
- The CPSC standard does not stifle real innovation. It does require the impact performance consumers need along with
anything new.
- "Back in 2008 most people were only beginning to grasp the seriousness of concussions." But an ASTM task group had
already been working on concussion and rotational injury testing concepts for more than a decade.
The article is intended to be provocative from the title to the end, and it succeeds. We would have welcomed more balance
in the new technology commentary.
Note: the original email newsletter said that Bell Sports was not supporting the addition of low velocity impact
tests to the ASTM standard. Bell has informed us that we were mistaken, and they are indeed supporting the effort to make
that change.
The Helmet Update - Bicycle Helmet Safety Institute
Randy Swart, Editor
4611 Seventh Street South
Arlington, VA 22204-1419 USA
(703) 486-0100 (voice)
(703) 486-0576 (fax)
www.helmets.org