CPSC Releases Draft of Final Rule
Summary: BHSI's comments on CPSC's Final Rule for their bicycle helmet standard, published in the Federal Register on March 10, 1998. Most of this was sent out as an email message: The Helmet Update Volume 15, No. 3
In late December the Consumer Product Safety Commission released a draft for its bicycle
helmet standard. This draft goes to the Commissioners for final approval in mid-January and
if approved unchanged will be the U.S. law for helmets in March, 1999.
Staff is attempting to have this rule approved without an additional comment period despite
some changes from the previous draft, issued in December, 1995. The changes are not considered
by the legal staff at CPSC to require an additional comment period, although some are
significant. None of the changes was unexpected. The standard continues to be quite similar
to the Snell B-90 and ASTM standards, and should be met by virtually any well-made helmet on
the market today without major modifications.
There were several changes worthy of note in this draft:
1. Children's Helmets.
CPSC is dropping most of the distinctions it had proposed between helmets for children under 5
and helmets for adults. That means upping the acceptable peak g's in impact testing for kid's
helmets to the usual 300 instead of the lower 250 that had been proposed. It also means continuing
to use adult-weight headforms to test child helmets instead of the proposed change to lighter
headforms more representative of child head weight, a change now being made in the ASTM standard.
The only difference for toddler helmets retained in the new draft is the requirement for
additional head coverage in helmets for children aged 1 to 5 years.
The changes in g level and headform mass are explained by staff in terms of the effects of the
requirement on the helmets. Liners would have to be softer to meet the lower g levels. That
means that given unchanged technology they would bottom out at lower force levels, unless they
were made thicker. CPSC seems to buy the manufacturers' argument that they can't make helmets
any thicker or consumers will not accept them, and the implied argument that the technology is
not subject to improvement. Some in the injury prevention community have recommended that no
changes be made because child helmets are already offering good protection and there is no data
to prove that changing the helmets will result in better protection and lower injury rates. The
additional coverage which had been required for toddler helmets in the December draft is in line
with trends in ASTM standards. These changes could be considered significant, but CPSC has
retreated into orthodoxy on this issue and probably does not need a comment period for this one.
Here is an elegant argument from Jim Sundahl of Bell Sports on why
CPSC should not have backed off on the change - his field experience indicates that kids
need softer foam. We agree.
2. Impacts on the Curbstone Anvil
CPSC has decided that the wicked curbstone anvil should not be used more than once on a given
helmet sample, but that a cold, hot, wet and ambient sample should all be impacted once with
the curbstone.
Clever lab technicians delight in bashing helmets with this very severe anvil, setting up
cracks with the first impact and propagating them with the second to "blow the helmet apart."
The test is in fact not representative of real-world crashes. CPSC explains that manufacturers
had suggested that only an ambient helmet be impacted with the curbstone, but they believe
that a helmet should be able to withstand a single curbstone hit in any condition, so have
added three more samples to the testing protocol to permit one curbstone impact on each of
the four conditions. The wet sample is probably the most severe, since the water lubricates
the anvil and facilitates its penetration. So a second set of four helmets will be tested
with a single impact on the curbstone anvil.
CPSC also has clarified the impacting schedule, and has made it clear that it will use any
combination of anvils, sites within the test line and conditioning environments to attempt to fail
the helmet. The new draft also requires a system accuracy check for the impact test rig. Drop
heights remain at 2 meters on the flat anvil and 1.2 meters on the hemispherical and curbstone
anvils.
3. Test Rig
CPSC had specified in December that only a monorail guidance system could be used for the drop
tests. This provoked strong protests from users of twin-wire guidance systems, who not only
represent the majority of the testing community in the U.S. but who almost universally consider
the monorail inferior. The Snell Foundation is a leading advocate of twin-wire systems, having
used them for production testing for the last decade, and most manufacturers also have twin-wire
rigs. This draft permits either rig.
CPSC conducted a "round robin" test, sending test helmets to seven labs and comparing the
results. They concluded that only one situation produced a significant difference in data
between twin wire and monorail: the now-dropped double-curbstone hit. Their conclusion was
that there would not be cross-lab problems due to the differing rigs, so both are to be
permitted. We remain skeptical on this score, based on allegations by lab technicians over
the years that there are indeed some significant differences in data depending on which rig
the test was performed on. In fact, CPSC's study of the testing shows that monorails produce
slightly higher g levels, and have a little more variation between labs as well. But CPSC has
only a monorail (despite a Snell offer of a free twin-wire rig), so both types of rigs will
remain in use for the duration of this standard. One result is that the standard specifies
a broader range of permissible variation in test instrument readings on the calibration test,
corresponding to a 10 per cent variation between labs.
4. Labeling
CPSC made minor changes in the labeling requirements, including specifying that the word
"WARNING" must precede some labels, and eliminating the "Not for Motor Vehicle Use" label.
Eliminating the Not For Motor Vehicle Use label follows current ASTM practice, where helmets
are being specified in a positive statement such as "For use in bicycling" rather than in an
incomplete list of inappropriate uses.
CPSC has also added a requirement that the labels contain the manufacturer's telephone number,
and that the date of manufacture be uncoded to assist in recalls, a significant improvement over
coded dates.
5. Reflectivity
Last year CPSC tested helmets at night with and without reflective tape meeting the proposed ASTM
helmet reflectivity standard. Under this particular testing protocol, the average distance at
which a bicycle was detected as an object or identified as a bicycle was only reduced by 29 feet,
from 777 feet to 748 feet. Staff concluded that the reduction was not significant, providing no
basis for adding the requirement to the standard. But the study does state "There is also an
indication that helmet might be a significant factor, but without further testing this cannot be
verified. There is no further information. We fault the study primarily for using subjects who
were alert, not fiddling with radios or dialing cell phones, not abusing controlled substances and
not drunk. We suspect that few if any of them had eyeglasses that needed changing or windshields
that were smeared. And we assume that the cars had two working headlights, two working windshield
wipers and well-maintained brakes and steering. As a result, their sample of drivers does not
correlate well with the population of drivers who run over cyclists at night. We understand the
CPSC action, but hope that subsequent research may show the advantages of reflective materials on
helmets that we think are evident at night. We'll bring the keg to condition the drivers!
6. Definition of a Bicycle Helmet
CPSC has made a change in the definition of the bicycle helmet to " any headgear that is either
marketed as, or implied through marketing and/or promotional information to be, a device intended
to provide protection from head injuries while riding a bicycle."
Although this change was in response to a comment from Bell Sports, concerned that their
non-bicycle helmets might have been covered under previous language, we are pleased to see it. We
hope that it will assist in addressing our complaints to CPSC about the "toy helmets" turning up
now in discount and toy stores which emulate a bike helmet but are almost completely without
energy management capabilities. They are labeled as toys, but sometimes are sold in the bicycle
section of the store. Under this definition we think the store is guilty of violating the standard
if the product is marketed with other bicycle accessories, no matter how it is labeled.
7. Summary
We are pleased that this draft has finally emerged and that the standard could take effect as
early as February of 1999. The original drafts were well done, and this one improves on them in
most respects. We are disappointed that child helmets will continue to be measured by adult
tests, and that the benefits of a reflectivity requirement were not demonstrated by CPSC's tests.
We hope that CPSC will not lose sight of the need to revise this standard as new information and
new technologies come to light. The draft will be considered by the Commission on January 21st,
and voted on by the Commissioners on February 5th. We hope that it will be approved by the
Commission in the following two weeks, which would permit it to take effect one year after
publication in the Federal Register, making it March of 1999. When it does it will become the law of the land, and failure to meet this
bicycle helmet standard may have serious legal consequences,
There was a page with the full briefing package in five parts, but it is gone.
See our page of CPSC docs for what we saved from that era.
ASTM Makes Significant Progress in December Meeting
The ASTM headgear committee met in December in San Diego and made progress on improvements or
adoption of a number of standards for helmets for bicycling, skateboarding, whitewater,
equestrian sports, baseball, skiing and more.
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
|