Safety Standard for Bicycle Helmets
Federal RegisterMar 10, 1998
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SUMMARY: Pursuant to the Children's Bicycle Helmet Safety Act of 1994,
the Commission is issuing a safety standard that will require all
bicycle helmets to meet impact-attenuation and other requirements.
The standard establishes requirements derived from one or more of
the voluntary standards applicable to bicycle helmets. In addition, the
standard includes requirements specifically applicable to children's
helmets and requirements to prevent helmets from coming off during an
accident. The standard also contains testing and recordkeeping
requirements to ensure that bicycle helmets meet the standard's
requirements.
DATES: Effective Date: This rule is effective March 10, 1999.
Applicability Dates: This rule applies to bicycle helmets
manufactured after March 10, 1999. Interim mandatory standards that
went into effect on March 17, 1995, will continue to apply to bicycle
helmets manufactured from March 17, 1995, until March 10, 1999,
inclusive. In addition, as of March 10, 1998, firms will have the
option of marketing helmets meeting the standard in this final rule
before its effective date.
Incorporation by Reference: The incorporation by reference of
certain publications listed in the rule is approved by the Director of
the Federal Register as of March 10, 1999.
FOR FURTHER INFORMATION CONTACT: Frank Krivda, Office of Compliance,
Consumer Product Safety Commission, Washington, D.C. 20207; telephone
(301) 504-0400 ext. 1372.
SUPPLEMENTARY INFORMATION:
Outline of Contents
A. Introduction and Background
1. Introduction.
2. Injury and death data.
3. The Children's Bicycle Helmet Safety Act of 1994.
4. The current rulemaking proceeding.
B. Overall Description of Standard
1. Impact attenuation.
2. Children's helmets: head coverage.
3. Retention system.
4. Peripheral vision.
5. Labels and instructions.
6. Positional stability (roll off).
7. Certification labels and testing program.
8. Recordkeeping.
9. Interim standards.
C. The Final Standard--Comments, Responses, and Other Changes
1. Accident scenarios.
2. Future revisions.
3. Compliance with third-party standards as compliance with the
rule.
4. Scope of the standard.
a. Definition of ``bicycle helmet.''
b. Multi-activity helmets.
5. Projections.
6. Requirements for qualities of fitting pads.
7. Impact attenuation criteria.
a. Extent of protection.
b. Distance between impacts.
c. Impact velocity tolerance.
d. Other children's requirements: peak g-value and drop mass.
8. Impact attenuation test rig.
a. Type of test rig.
b. Accuracy check.
c. Test headform characteristics.
d. Alignment of anvils.
e. Definition of ``spherical impactor.''
9. Impact attenuation test procedure.
a. Anvil test schedule and use of curbstone anvil.
b. Definition of ``comfort padding.''
c. Testing on more than one headform.
d. Number of helmets required for testing.
10. Helmet conditioning.
a. Low-temperature environment: temperature range.
b. Water immersion environment.
c. Reconditioning time.
11. Labels.
a. Label format and content.
b. Use label.
c. Labeling for cleaning products.
d. Warning to replace after impact.
e. Durability of labels.
f. Labels on both helmets and boxes.
12. Instructions for fitting children's helmets.
13. Retention system strength test.
14. Positional stability test.
15. Vertical vision.
16. Reflectivity.
17. Hard-shell requirements.
D. Certification Testing and Labeling
1. General.
2. The certification rule.
3. Reasonable testing program.
a. Changes in materials or vendors.
b. Pre-market clearance and market surveillance.
4. Certificate of compliance.
a. Coding date of manufacture.
b. Telephone number on label.
c. Certification label on children's helmets.
d. Minimum age on labels for children's helmets.
e. Identifying the Commission.
f. Certification label on packaging.
E. Recordkeeping
1. General.
2. Location of test records--time for production.
3. Length of records retention.
F. Regulatory Flexibility Act Certification
G. Environmental Considerations
H. Paperwork Reduction Act
I. Executive Orders
List of Subjects in 16 CFR Part 1203
Part 1203--Safety Standard for Bicycle Helmets
A. Introduction and Background
1. Introduction
In this notice, the United States Consumer Product Safety
Commission (``Commission'' or ``CPSC'') issues a mandatory safety
standard for bicycle helmets.1
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\1\ The standard was approved by the Commission unanimously, by
a vote of 3-0. Chairman Anne Brown, Commissioner Mary S. Gall, and
Commissioner Thomas Moore each issued a separate statement
concerning the vote. Copies of these statements are available from
the Office of the Secretary.
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2. Injury and Death Data
Data from the National Center for Health Statistics (``NCHS'')
indicated that in 1993 there were 907 pedalcyclist (primarily bicycle-
related) deaths in the United States. Of these, 17 (about 2%) were of
children under the age of 5 years. Research has shown that
approximately 60% of all bicycle-related deaths involved head injury.
For children under age 5, about 64% involved head injury.2
Information on the impact forces involved in these fatal incidents was
not available, although about 90% of the pedalcyclist deaths, including
those of children under age 5, involved collisions with motor vehicles.
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\2\ Sacks, Jeffrey, J., MPH; Holmgreen, Patricia, MS; Smith,
Suzanne M., MD; Sosin, Daniel M., MD. ``Bicycle-Associated Head
Injuries and Deaths in the United States from 1984 through 1988,''
Journal of the American Medical Association 266 (December 1991):
3016-3018. Sosin, Daniel M., MD, MPH; Sacks, Jeffrey J., MD, MPH;
and Webb, Kevin W., ``Pediatric Head Injuries and Deaths from
Bicycling in the United States,'' Pediatrics 98 (November 1996):
868-870.
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Based on data from CPSC's National Electronic Injury Surveillance
System (``NEISS''), there were an estimated 566,400 bicycle-related
injuries treated in U.S. hospital emergency rooms in 1996. Of these,
approximately 30% involved the head and face. A higher proportion of
head injuries and facial injuries occurred to young children than to
older victims.
CPSC's NEISS data showed that the types of injuries to young
children were somewhat different from those to older children and
adults. Younger children had a smaller proportion of concussions and
internal injuries to the head than did older victims, as well as a
larger proportion of relatively minor head injuries (i.e., lacerations,
contusions, and abrasions). The extent to which these differences can
be attributed to the use of helmets, other aspects of the hazard
scenario, or the physiology of young children, is not known. It is also
possible that caregivers are more likely to bring young children to the
emergency room for relatively minor injuries.
[[Page 11713]]
A 1993 Commission staff study of bicycle hazards indicated that
when other factors were held constant statistically, the injury risk
for children under age 15 was over five times the risk for older
riders.3 This study also indicated that children were at
particular risk of head injury. About one-half of the injuries to
children under age 10 involved the head, compared to one-fifth of the
injuries to older riders. This may have been in part because children
were significantly less likely to have been wearing a helmet than were
older victims (5% of victims younger than 15 were wearing a helmet,
compared to 30% of those 15 and older). However, detailed information
relating the type of helmet, age of user, and other aspects of the
hazard scenario to head injury severity was not available from that
study. A Commission study on bicycle and helmet usage patterns found
that in 1993 about 18% of bicyclists wore helmets.4
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\3\ Tinsworth, Deborah K., MS; Polen, Curtis; and Cassidy,
Suzanne. ``Bicycle-Related Injuries: Injury, Hazard, and Risk
Patterns,'' International Journal for Consumer Safety I (December
1994): 207-220.
\4\ Rogers, Gregory B. ``The Characteristics and Use Patterns of
Bicycle Riders in the United States,'' Journal of Safety Research 25
(1994): 83-96.
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A 1996 study of about 3,400 injured bicyclists in the Seattle,
Washington, area included an evaluation of the protective effectiveness
of helmets in different age groups.5 When bicyclists treated
in hospital emergency rooms for head injuries were compared to
bicyclists who sought care for other types of injuries at the same
emergency rooms, helmet use was associated with a reduction in the risk
of any head injury by 69%, brain injury by 65%, and severe brain injury
by 74%.
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\5\ Thompson, Diane C., MS; Rivara, Frederick P., MD, MPH; and
Thompson, Robert S., MD. ``Effectiveness of Bicycle Safety Helmets
in Preventing Head Injuries,'' Journal of the American Medical
Association 276 (December 1996): 1968-1973.
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By age group, this study showed that the reduction in the risk of
head injury ranged from 73% for children under 6 years to 59% for teens
in the 13-19 year-old age group.6 Based on the results of
their study, the authors concluded that helmets were effective for all
bicyclists, regardless of age, and that there was no evidence that
children younger than 6 years need a different type of helmet. However,
for children younger than 6 years, there was only one helmeted child
with a brain injury (a concussion), and no helmeted children with
severe brain injuries. Thus, the protective effects of helmets on brain
injuries and severe brain injuries were not calculated for this age
group.
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\6\ The estimated reduction in risk for children 6-12 years of
age was 70%.
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A widely-cited 1989 study, published by the same authors, found
that riders with helmets had an 85% reduction in their risk of head
injury, and an 88% reduction in their risk of brain injury, when
compared to cyclists without helmets.7 These results were
found when patients who sought emergency room care for bicycle-related
head injuries were compared to bicyclists in the community who had
crashes, regardless of injury or medical care. A recent study indicated
that helmets may protect more against head injuries than against some
facial injuries.8
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\7\ Thompson, Robert S., MD; Rivara, Frederick P., MD, MPH; and
Thompson, Diane C., MS. ``A Case Control Study of the Effectiveness
of Bicycle Safety Helmets,'' The New England Journal of Medicine 320
(May 1989): 1361-1367.
\8\ Recent research indicated that helmets reduced the risk of
serious injury to the upper and middle face by about 65%, but had no
significant effect on serious injury to the lower face. Thompson,
Diane C., MS; Nunn, Martha E., DDS; Thompson, Robert S., MD; and
Rivara, Frederick P., MD, MPH. ``Effectiveness of Bicycle Safety
Helmets in Preventing Serious Facial Injury.'' Journal of the
American Medical Association 276 (December 1996): 1974-1975.
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3. The Children's Bicycle Helmet Safety Act of 1994
On June 16, 1994, the Children's Bicycle Helmet Safety Act of 1994
(the ``Act'' or ``the Bicycle Helmet Safety Act'') became law. 15
U.S.C. 6001-6006. The Act provides that bicycle helmets manufactured
after March 16, 1995, conform to at least one of the following interim
safety standards: (1) The American National Standards Institute (ANSI)
standard designated as Z90.4-1984, (2) the Snell Memorial Foundation
standard designated as B-90, (3) the ASTM (formerly the American
Society for Testing and Materials) standard designated as F 1447, or
(4) any other standard that the Commission determines is appropriate.
15 U.S.C. 6004(a)-(b). On March 23, 1995, the Commission published its
determination that five additional voluntary safety standards for
bicycle helmets are appropriate as interim mandatory standards. 60 FR
15,231. These standards are ASTM F 1447-1994; Snell B-90S, N-94, and B-
95; and the Canadian voluntary standard CAN/CSA-D113.2-M89. In that
notice, the Commission also clarified that the ASTM standard F 1447
referred to in the Act is the 1993 version of that standard. The
interim standards are codified at 16 CFR 1203.
The Act directed the Consumer Product Safety Commission to begin a
proceeding under the Administrative Procedure Act, 5 U.S.C. 553, to:
a. Review the requirements of the interim standards described above
and establish a final standard based on such requirements;
b. Include in the final standard a provision to protect against the
risk of helmets coming off the heads of bicycle riders;
c. Include in the final standard provisions that address the risk
of injury to children; and
d. Include additional provisions as appropriate. 15 U.S.C. 6004(c).
The Act provides that the final standard shall take effect 1 year
from the date it is issued. 15 U.S.C. 6004(c). The Act further provides
that the final standard shall be considered to be a consumer product
safety standard issued under the CPSA. Section 9(g)(1) of the CPSA
provides that a ``consumer product safety standard shall be applicable
only to consumer products manufactured after the effective date.''
Thus, the final standard, which the Commission is issuing in this
notice, will become effective March 10, 1999, as to products
manufactured after that date. The Act also provides that failure to
conform to an interim standard shall be considered a violation of a
consumer product safety standard issued under the Consumer Product
Safety Act (``CPSA''), 15 U.S.C. 2051-2084.
The Act states that the CPSA's provisions regarding rulemaking
procedures, statutory findings, and judicial review (15 U.S.C. 2056,
2058, 2060, and 2079(d)) shall not apply to the final standard or its
rulemaking proceeding. 15 U.S.C. 6004(c).
The final rule is codified at 16 CFR 1203 and will replace the
interim standards as to bicycle helmets manufactured on or after March
11, 1999. 15 U.S.C. 6004(d). In addition, the final standard is also
being designated an interim standard, so that firms will have the
option of marketing helmets meeting CPSC's final standard before its
effective date. Because providing this additional interim standard is a
substantive rule that grants an exemption or relieves a restriction,
the 30-day delay of an effective date otherwise required by 5 U.S.C.
553(d) is inapplicable, and this designation is effective March 10,
1998.
4. The Current Rulemaking Proceeding
The Commission reviewed the bicycle helmet standards identified in
the Act (ANSI, ASTM, and Snell), as well as international bicycle
helmet standards and draft revisions of the ANSI, ASTM, and Snell
standards that were then under consideration. Based on this review, the
Commission developed a proposed safety standard for bicycle
[[Page 11714]]
helmets. 59 FR 41,719 (August 15, 1994).
The Commission received 37 comments on that proposed bicycle helmet
standard from 30 individuals and organizations. After considering these
comments and other available information, the Commission proposed
certain revisions to the originally proposed standard. 60 FR 62662
(December 6, 1995).
In response to the second proposal, the Commission received 31
comments. These comments, and additional data that have been received
by the Commission since the second proposal, are discussed in Sections
C-E of this notice.
B. Overall Description of the Standard
The major features of the standard issued in this notice are
described below.
1. Impact Attenuation
The standard establishes a performance test to ensure that helmets
will adequately protect the head in a collision. This test involves
securing the helmet on a headform and dropping the helmet/headform
assembly to achieve specified velocities so that the helmet impacts a
fixed steel anvil. The helmet must provide protection at all points
above a line on the helmet that has a specified relation to the
headform.
Under the standard, the helmet is tested with three types of anvils
(flat, hemispherical, and ``curbstone,'' as shown in Figures 11, 12,
and 13 of the standard). These anvils represent shapes of surfaces that
may be encountered in actual riding conditions. Instrumentation within
the headform records the headform's impact in multiples of the
acceleration due to gravity (``g''). Impact tests are performed on
different helmets, each of which has been subjected to one of four
environmental conditions. These environments are: ambient (room
temperature), high temperature (117-127 deg.F), low temperature (1-
9 deg.F), and immersion in water for 4-24 hours.
Impacts are specified on a flat anvil from a height of 2 meters and
on hemispherical and curbstone anvils from a height of 1.2 meters.
Consistent with the requirements of the ANSI, Snell, and ASTM
standards, the peak headform acceleration of any impact shall not
exceed 300 g for an adult helmet, the value originally proposed for
both adult and child helmets. In the revised proposed standard, the
acceptable g value for children's helmets was reduced to 250 g and a
lower headform drop mass than that for adults was specified (3.90 kg).
As explained in section C of this notice, however, the final rule
specifies that the 5-kg headform mass and the 300-g peak acceleration
criterion will apply to all helmets subject to the standard, as
specified in the original proposal.
The standard provides that a helmet fails the performance test if a
failure can be induced under any combination of impact site, anvil
type, anvil impact order, or conditioning environment permissible under
the standard. Thus, the Commission will test for a ``worst case''
combination of test parameters. What constitutes a worst case may vary,
depending on the particular helmet involved.
2. Children's Helmets: Head Coverage
The standard specifies that helmets for small children (under age
5) must cover a larger portion of the head than must helmets for older
persons. A study by Biokinetics & Associates Ltd. found differences in
anthropometric characteristics between young children's heads and older
children's and adult's heads.9
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\9\ Heh, S., Log of ASTM FO8.53 Headgear Subcommittee meeting
held May 21, 1992, date of entry June 17, 1992. Office of the
Secretary, U.S. Consumer Product Safety Commission, Washington, DC
20207.
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3. Retention System
The standard requires that helmets be able to meet a test of the
dynamic strength of the retention system. This test ensures that the
chin strap is strong enough to prevent breakage or excessive elongation
of the strap that could allow a helmet to come off during an accident.
The test requires that the chin strap remain intact and not
elongate more than 30 mm (1.2 in) when subjected to a ``shock load'' of
a 4-kg (8.8-lb) weight falling a distance of 0.6 m (2 ft) onto a steel
stop anvil (see Figure 8). This test is performed on one helmet under
ambient conditions and on three other helmets after each is subjected
to one of the different hot, cold, and wet environments.
4. Peripheral Vision
Section 1203.14 of the standard requires that a helmet shall allow
a field of vision of 105 degrees to both the left and right of straight
ahead. This requirement is consistent with the ANSI, ASTM, and Snell
standards.
5. Labels and Instructions
Section 1203.6 of the standard requires certain labels on the
helmet. These labels provide the model designation and warnings
regarding the protective limitations of the helmet. The labels also
provide instructions regarding how to care for the helmet and what to
do if the helmet receives an impact. The labels also must carry a
warning that for maximum protection the helmet must be fitted and
attached properly to the wearer's head in accordance with the
manufacturer's fitting instructions.
The standard also requires that helmets be accompanied by fitting
and positioning instructions, including a graphic representation of
proper positioning. As noted above, the standard has performance
criteria for the effectiveness of the retention system in keeping a
helmet on the wearer's head. However, these criteria may not be
effective if the helmet is not well matched to the wearer's head and
carefully adjusted to obtain the best fit.
To avoid damaging the helmet by contacting it with harmful common
substances, the helmet must be labeled with any recommended cleaning
agents, a list of any known common substances that will cause damage,
and instructions to avoid contact between such substances and the
helmet.
6. Positional Stability (Roll Off)
The standard specifies a test procedure and requirement for the
retention system's effectiveness in preventing a helmet from ``rolling
off'' a head. The procedure specifies a dynamic impact load of a 4-kg
(8.8-lb) weight dropped from a height of 0.6 m (2 ft) to impact a steel
stop anvil. This load is applied to the edge of a helmet that is placed
on a headform on a support stand (see Figure 7). The helmet fails if it
comes off the headform during the test.
The safety requirements discussed in paragraphs (1)-(6) above are
issued pursuant to the Bicycle Helmet Safety Act and are codified as
Subpart A of the Safety Standard for Bicycle Helmets.
7. Certification Labels and Testing Program
Under the authority of section 14(a) of the CPSA, the Commission is
also issuing certification testing and labeling requirements to ensure
that bicycle helmets meet the standard's safety requirements. These
certification requirements are in Subpart B of the Safety Standard for
Bicycle Helmets and are discussed in section D of this notice.
8. Recordkeeping
Under the authority of section 16(b) of the CPSA, the Commission is
issuing requirements that manufacturers (including importers) maintain
records of the required certification testing. These recordkeeping
requirements are found in Subpart C of the Safety
[[Page 11715]]
Standard for Bicycle Helmets and are discussed in section E of this
notice.
9. Interim Standards
The interim standards, which are currently codified as 16 CFR 1203,
will continue to apply to bicycle helmets manufactured from March 16,
1995, to March 11, 1999. Accordingly, the interim standards will
continue to be codified, as Subpart D of the standard. Also, Subparts
A-C of the standard are being added as an interim standard, so that
firms will have the option of marketing helmets meeting CPSC's final
standard before its effective date.
C. The Final Standard--Comments, Responses, and Other Changes
This section discusses comments on the second proposal, as well as
other issues that were dealt with in deciding the requirements of the
final rule. Numbers in brackets refer to the number assigned by the
Commission's Office of the Secretary to a comment on the second
proposal.
1. Accident Scenarios
Mr. Frank Sabatano [14], President of the London Bridge BMX
Association, recommended that bike helmets be constructed so as to
accommodate more serious accidents that might result from a child
bicycle racing or jumping rather than merely riding on a path or
street.
While no helmet can protect against every conceivable impact, the
available evidence supports the conclusion that helmets designed to
meet the CPSC standard will be very effective in protecting against
serious injury within a wide range of common bicycle riding conditions.
This would include many of the impact conditions that could occur
during racing or jumping. Furthermore, a standard for all bicycle
helmets has to balance the benefits of more protective helmets against
the additional cost, weight, bulk, and discomfort that more protection
may impose. Such undesirable qualities may discourage many users from
wearing helmets designed to protect against very severe impacts, which
could more than cancel the effects of the additional protective
qualities. Thus, the force with which the helmets are impacted in the
standard's performance test has not been increased.
2. Future Revisions
Randy Swart, Director of the Bicycle Helmet Safety Institute [16],
suggested that the following items be considered as future revisions to
the CPSC standard as progress in head protection research continues:
a. A test that requires the retention system to be easily adjusted
for good fit.
b. A test for protection against rotational injury.
c. A test to limit localized loads or ``point loading.''
d. A test for damage to the helmet by hair oil or other common
consumer preparations.
e. A test of the retention system after impact to simulate field
conditions.
f. A test to ensure that visors and mirrors are shatter-resistant
and easily peel off in a crash.
The Commission agrees that it is important to periodically review
research related to improvements in head protection to determine if
revisions should be considered for the CPSC bicycle helmet standard.
3. Compliance With Third-Party Standards as Compliance With the Rule
Jane McCormack [7] requested that the Commission ensure that bike
helmets meet the Snell requirements. Norte Vista Medical Center [15]
requested that helmets certified to the Snell B-95 or Snell N-94
standards be considered to be in compliance with the mandatory
standard.
The Commission declines to make these changes. One of the
objectives of the Bicycle Helmet Safety Act is to establish a unified
bicycle helmet standard that is recognized nationally by all
manufacturers and consumers. It would defeat Congress' intent to add
language to the regulation stating that certified conformance to any
existing voluntary standard satisfies compliance with the mandatory
rule.
4. Scope of the Standard
a. Definition of ``Bicycle Helmet''
The original proposal defined bicycle helmet as ``any headgear
marketed as suitable for providing protection from head injuries while
riding a bicycle.'' The definition of bicycle helmet in the second
proposal included not only products specifically marketed for use as a
bicycle helmet but also those products that can be reasonably foreseen
to be used for that purpose.
Bell Sports [12] suggested that the definition of bicycle helmet
should not include all products with a reasonably foreseeable use as a
device intended to provide protection from head injuries while riding a
bicycle. Bell maintains there are many helmets that have a foreseeable
use by bike riders that should not have to be certified to a bike
helmet standard (e.g., baseball and roller hockey helmets).
The respondent suggested that football helmets, baseball batting
helmets, and motorcycle helmets will also have ``easily foreseeable''
uses as bicycle helmets.
The Commission did not intend for the definition of bicycle helmet
to include football helmets, baseball batting helmets, and motorcycle
helmets that are not marketed for use while bicycling. It seems
unlikely that a helmet that is not marketed or promoted for bicycle use
will have a reasonably foreseeable use as a bicycle helmet. Thus, the
``reasonably foreseeable'' language is unnecessary. Therefore, in order
for the definition to provide more guidance, the ``reasonably
foreseeable'' language has been deleted, and the definition of bicycle
helmet has been changed to read: ``Bicycle helmet means any headgear
that either is specifically marketed as, or implied through marketing
or promotion to be, a device intended to provide protection from head
injuries while riding a bicycle.''
Helmets specifically marketed for exclusive use in a designated
activity such as skateboarding, rollerblading, baseball, roller hockey,
etc., would be excluded from this definition because the specific focus
of their marketing makes it unlikely that such helmets would be
purchased for other than their stated use. However, a multi-purpose
helmet--one marketed or represented as providing protection either
during general use or in a variety of specific activities other than
bicycling--would fall within the definition of bicycle helmet if a
reasonable consumer could conclude, based on the helmet's marketing or
representations, that bicycling is among the activities in which the
helmet is intended to be used.
In making this determination, the Commission will consider the
types of specific activities, if any, for which the helmet is marketed,
the similarity of the appearance, design, and construction of the
helmet to other helmets marketed or recognized as bicycle helmets, and
the presence, prominence, and clarity of any warnings, on the helmet or
its packaging or promotional materials, against the use of the helmet
as a bicycle helmet. The presence of warnings or disclaimers advising
against the use of a multi-purpose helmet during bicycling is a
relevant, but not necessarily controlling, factor in the determination
of whether a multi-purpose helmet is a bicycle helmet. A multi-purpose
helmet marketed without specific reference to the activities in which
the helmet is to be used will be presumed to be a bicycle helmet.
b. Multiple-Activity Helmets
Some commenters on the original proposal recommended that the CPSC
include provisions for children's bicycle helmets to provide protection
in
[[Page 11716]]
activities in addition to bicycling, such as skateboarding, skating,
sledding, and the like. Two commenters recommended that the CPSC bike
helmet standard also apply to helmets marketed for roller skating and
in-line skating. Other comments stated that the Commission should not
delay promulgation of the bike helmet standard while multi-activity
issues are explored.
The Commission did not propose that the standard address activities
other than bicycling, because the CPSC's authority under the Bicycle
Helmet Safety Act is to set mandatory requirements for bicycle helmets.
Establishing criteria for products other than bicycle helmets would
require the Commission to follow the procedures and make the findings
prescribed by the CPSA or the Federal Hazardous Substances Act
(``FHSA'').
The National Safe Kids Campaign (``NSKC'') [22] and the Consumer
Federation of America (``CFA'') [23] recognized that the scope of the
CPSC standard must be for bicycle helmets, but requested the Commission
to move forward in investigating the issues related to multi-activity
helmets. In a comment on the revised proposal, Mr. Frank Sabatano,
President of the London Bridge BMX Association [14], recommended that
bicycle helmets should serve as multi-purpose protective devices for
various sports such as bicycle riding, bicycle racing, skateboarding,
and in-line skating.
The Commission intends to monitor developments relevant to the
multi-activity issue. Wheeled recreational activities such as
traditional roller skating and in-line skating are typically conducted
on the same surfaces as bicycling, and can generate speeds similar to
bicycling. Therefore, it is reasonable to assume that helmets that meet
the requirements in the CPSC bike helmet standard will also provide
head protection for roller/in-line skating and perhaps some other
recreational activities. However, as discussed in the December 6, 1995,
Federal Register notice on the proposed rule, the Commission does not
have sufficient data on the benefits and costs of additional features
directed at injuries incurred in activities other than bicycling to
make the statutory findings that would be needed to issue a requirement
for such features under either the CPSA or FHSA. Also, procedures in
addition to those required by the Bicycle Helmet Safety Act would have
to be followed. The Commission does not want to delay establishment of
a mandatory bicycle helmet standard in order to pursue rulemaking for
other types of helmets. Accordingly, the final standard only addresses
requirements for bicycle helmets. However, as discussed below, the
Commission will examine what actions it could take to encourage the use
of bicycle helmets in activities that present head injury risks similar
to those in bicycling.
NSKC [22] also urged the CPSC to work with community-based
organizations to develop a comprehensive educational campaign regarding
the importance of wearing a federally-approved bicycle helmet when
participating in non-motorized activities other than bicycling. The
Commission will consider what activities are appropriate in this regard
when setting its priorities for future activities.
5. Projections
Projections on the inner or outer surface of a helmet can
concentrate applied forces and cause injuries. Therefore, the revised
proposed standard provided that projections on the outer surface would
not exceed 7 mm (0.28 in) unless they break away or collapse on impact
and that projections on the helmet's interior not make contact with the
headform during testing.
NSKC [22] urged that the Commission prohibit any external
projections on helmets intended for children. NSKC believes that
external projections, such as visors, are unnecessary components of
helmets intended for children.
With regard to a possible hazard from external projections on
children's helmets, Sec. 1203.7 of the standard requires that helmets
must pass all tests, both with and without any attachments that may be
offered by the manufacturer. This provision, and the requirement that
any external projections shall break away or collapse, will address the
potential hazard of external projections on helmets intended for riders
of all ages. The proposed language is consistent with existing
voluntary standards, and no changes were made in response to this
comment.
SwRI [2] remarked that the proposed standard does not state how to
determine if an internal projection makes contact with the headform
during testing. NSKC [22] also suggested that instead of requiring
inner surface projections to not exceed 2 mm, the inside of the helmet
should contain no sharp edges or rigid internal projections.
After considering these comments, the Commission decided to revise
the section on internal projections to eliminate the requirement that
internal projections not make contact with the headform during testing,
while retaining the requirement that such projection not exceed 2 mm
(0.08 in). The purpose of this section is to prohibit potentially
hazardous projections but make some allowance for common helmet
construction practices. The language above is consistent with Snell
helmet standards, and the Commission is not aware of safety problems
associated with projections on helmets meeting existing standards.
6. Requirements for Qualities of Fitting Pads
NSKC [22] urged the Commission to include safety requirements for
fitting pads in the final standard. The commenter asserted that since
fitting pads are often necessary to ensure a secure fit, the standard
should address the integrity of the materials used to construct them,
as well as their thickness, durability, and adhesiveness.
CPSC staff has no information that long-term integrity of fitting
pads is a problem with helmets meeting existing standards. The interim
mandatory standards have no provisions of the type suggested by the
commenter. Introducing new requirements for fitting pads is not
essential at this time, and no change to the proposed standard has been
made in response to this comment.
7. Impact Attenuation Criteria
a. Extent of Protection
The originally proposed CPSC standard, and current U.S. voluntary
bicycle helmet standards, specified an extent-of-protection boundary
and an impact test line. The extent-of-protection boundary defines the
area of the head that must be covered by the helmet. The impact test
line designates the lowest point on the helmet where the center of an
anvil may be aligned for testing. The second proposal specified a
single impact test line and no extent-of-protection boundary
requirement. Not requiring specific helmet coverage allows
manufacturers the flexibility to include desirable features, such as a
central rear vent, provided the features do not hinder the helmet's
ability to meet the impact requirements if tested anywhere on or above
the impact test line. Accordingly, the Commission deleted the extent-
of-protection boundary from the revised proposed standard.
In commenting on the latter proposal, Snell [28] discussed the
practical problems in certifying helmets when only an impact test line
is specified. Snell recommended that the standard be amended to require
coverage below the impact test line, particularly at the front and rear
of a helmet.
[[Page 11717]]
The Commission disagrees with this comment. Coverage does not imply
impact protection. The only area on the helmet required to pass impact
protection requirements is the area above the impact test line.
Therefore, it is unnecessary to specify additional coverage below the
test line.
The manufacturers of the Protective Headgear Manufacturing
Association (``PHMA'') [29] reported that they believed the proposed
CPSC standard requires coverage at the rear of the head lower than any
other standard. They stated that they are not aware of any studies
indicating that lower coverage at the rear is warranted. They also
stated their concern that the helmet-wearing public will not purchase
helmets that are perceived to be more ``clunky'' or ``bulbous,'' and
that helmets with extended coverage are likely be so perceived. Mr.
Becker of Snell [28] stated that the CPSC-proposed coverages are more
extensive than any current U.S. standard, except for Snell's B-95 and
N-94 helmet standards. He stated that unless the CPSC coverage is
changed, many contemporary helmet models that have protected their
wearers from life-threatening injury will disappear from the market.
Snell urged that the CPSC adopt the coverage described in the ASTM
F1447-94 or Snell B-90 standards. According to this commenter, these
coverages reflect the current state of the industry and should be
expected of every bicycle helmet.
The proposed CPSC impact test line is not lower at the rear of the
helmet than all other standards. The proposed CPSC impact test line is
somewhat lower at the rear of the helmet than the impact test lines in
the Snell B-90 and ASTM F1447 standards. However, the CPSC line is
higher at the rear of the helmet than the impact test lines in the
following interim mandatory standards: Snell B-95 and N-94, CAN/CSA-
D113.2, and ANSI Z90.4-1984.
CPSC is aware of two studies that show that it is not uncommon for
helmets involved in accidents to suffer impacts at the rear portion of
the helmet. A Bell Sports study of 1100 helmets involved in accidents
found that 26% of the impacts were at the rear of the helmet and that
the majority of these rear impacts occurred within 50 mm of the bottom
edge of the helmet.10 Another study, by Technisearch of
Australia, examined the effect of lowering the impact test line from
the Snell B-90 standard to the impact test lines in the Snell B-95 and
N-94 standards.11 The Technisearch study was based on
examinations of 104 bicycle helmets whose wearers sustained impacts to
the head during accidents. The study concluded that the B-90 standard
test line would have provided coverage for 51% of the impacts. The
impact test line of the B-95 standard would provide coverage for 65% of
the impacts. The increase from 51% to 65% was represented by 20
additional impact sites that would fall within the area of the B-95
coverage, including 8 impact sites at the rear portion of the helmet.
---------------------------------------------------------------------------
\10\ Dean Fisher and Terry Stern, ``Helmets Work!,'' Bell
Sports, Inc., AAAM/IRCOBI Conference, Lyon, France (September 1994).
\11\ Martin Williams, ``Test Line Requirements and Snell B-95
and N-94 Standards,'' Technisearch Engineering & Scientific Services
(August 1994).
---------------------------------------------------------------------------
One of the directions of the Children's Bicycle Helmet Safety Act
is to include provisions from existing appropriate standards for
adoption in the final CPSC standard. The CPSC impact test line is a
reasonable requirement that will improve the protective characteristics
of helmets overall, while falling within test lines of established
North American bicycle helmet standards.
b. Distance Between Impacts
A commenter on the original proposal recommended revising the
minimum distance between impact sites from the originally proposed
``one fifth the circumference of the helmet'' to 120 mm. The Commission
believed that 120 mm allows sufficient distance to minimize the effects
of impact site proximity and provides a more straightforward
measurement than the original one-fifth circumference criteria.
Accordingly, the Commission adopted this recommendation in the revised
proposal.
Two commenters on the revised proposal [27 and 29] recommended a
minimum distance between impacts of 150 mm, or about 6 inches. One of
these commenters stated that the CPSC made the minimum distance shorter
than those in voluntary standards.
The Commission selected the 120-mm impact spacing based on recently
balloted ASTM headgear standards. The Snell B-95 standard also
specifies a minimum impact separation of 120 mm. This distance is
consistent with the Snell B-90 specification of \1/6\th the maximum
helmet circumference, if calculated for smaller helmets. A minimum
impact spacing of 150 mm would limit flexibility in choosing impact
sites, especially on smaller helmets. Therefore, no change to the
proposed rule was made in response to this comment.
c. Impact Velocity Tolerance
The University of Southern California's Head Protection Research
Lab (``USC-HPRL'') [8] suggested that the tolerance for the impact
velocity be changed from 3% to -0% to +5% to ensure that
impact testing is done at no less than the specified velocity.
The difference between tolerances of 3% and -0%, +5%
has little practical significance for a 300-g criterion. Since the
commenter's suggestion would not produce a significant safety benefit,
the Commission made no change to the proposed rule in this regard.
d. Other Requirements for Children's Helmets: Peak-G Value and Drop
Mass
One of the provisions of The Children's Bicycle Helmet Safety Act
of 1994 is that the Commission include in the final CPSC standard
provisions that address the risk of injury to children. This does not
require that children's helmets be subject to requirements that differ
from those for adults' helmets; it requires only that the final
standard be appropriate for children's helmets. The issue of whether
special standard provisions for young children's helmets are needed has
been debated for several years by head protection experts.
A young child's skull has different mechanical properties than the
skull of an older child or adult. These differences are especially
evident for children under the age of 5 years. Their skulls have a
lower degree of calcification, making them more flexible than adult
skulls. During an impact to the head, the increased skull flexibility
results in a greater transfer of kinetic energy from the impact site to
the brain tissue. Besides the different mechanical properties, the mass
of a young child's head is also different from that of a more mature
person's head. Studies show that the head mass of children under the
age of 5 years ranges from approximately 2.8 to 3.9 kg. This mass is
lower than the 5-kg test headform mass specified in current U.S.
bicycle helmet standards.
The Commission first proposed a safety standard for bicycle helmets
on August 15, 1994. In that proposal, the only special provision for
helmets for children under 5 years was an increased area of head
coverage. On December 6, 1995, however, the Commission proposed special
provisions for headform mass, peak-g limit, and head coverage for
bicycle helmets for children under 5 years. The special children's
provisions were based on the ongoing work of voluntary standards
organizations and proposals at that time in the technical literature.
The following comparison shows the CPSC-proposed
[[Page 11718]]
test parameters for helmets for children under 5 years and for helmets
for older persons.
------------------------------------------------------------------------
Under 5 5 and older
------------------------------------------------------------------------
Mass of test headform............. 3.9 kg............... 5.0 kg
Peak-g limit...................... 250-g................ 300-g
Head coverage..................... More coverage at rear
and sides of head.
------------------------------------------------------------------------
The proposal for increased head coverage of children's helmets is
relatively uncontroversial, and the final rule contains this
requirement. However, the Commission has reassessed the proposed
headform mass and peak-g requirements. The Commission's conclusions are
discussed in detail below.
A few respondents to the proposed rule [8, 16] supported the lower
mass and lower peak-g provisions, believing that they will lead to an
improvement in head protection for small children. One of these
respondents, however, urged the Commission to consider the most recent
research on this subject before including the special provisions in a
final standard. One respondent [12] favored a reduced headform mass
provision, but did not recommend a reduced peak-g provision, stating
that it could result in a helmet with a lower margin of safety.
Several respondents [3, 4, 6, 9, 10, 13, 15, 18, 19, 27, 28, 29,
30] questioned whether it is advisable to move forward with the
provisions of a reduced-mass headform and a lower limit for peak
acceleration. Some respondents suggested that special children's
provisions should not be adopted since studies show that children's
helmets as they exist today provide excellent protection.
Studies by researchers at the Harborview Injury Prevention and
Research Center have shown that bicycle helmets that meet existing
standards are effective in protecting against serious head and brain
injuries.12 One of the items analyzed in the most recent
Harborview study was whether the protective effects of bicycle helmets
vary by the age of the user. For four age groups of riders, they
estimated the protective effect of helmets against three levels of
injury listed in order of increasing severity: (1) head injury, (2)
brain injury, and (3) severe brain injury.
---------------------------------------------------------------------------
\12\ Thompson, Robert S., MD; Rivara, Frederick P, MD, MPH; and
Thompson, Diane C., MS ``A Case Control Study of the Effectiveness
of Bicycle Safety Helmets,'' The New England Journal of Medicine 320
[May 1989]: 1361-1367. Thompson, Diane C., MS; Rivara, Frederick P,
MD, MPH; and Thompson, Robert S., MD. ``Effectiveness of Bicycle
Safety Helmets in Preventing Head Injuries,'' Journal of the
American Medical Association 276 (December 1996): 1968-1973.
---------------------------------------------------------------------------
Due to the small number of helmeted case subjects that suffered
brain injury and severe brain injury, Harborview researchers could not
estimate the protective effect of helmets against these injuries for
the under 6-year-old age group. Accordingly, the Commission has not
relied on this study in its consideration of whether special
requirements are needed for children's helmets. However, one of
Harborview's overall conclusions was that helmets are effective for all
bicyclists, regardless of age, and that there is no evidence that
children younger than 6 years need a different type of helmet.
The Commission requested technical views on this issue from Barry
Myers, M.D., Ph.D. Associate Professor, Department of Biomedical
Engineering, Duke University. In his report,13 Dr. Myers
explains that such modifications of the standard should be considered
only if it can be shown to improve the protective qualities of helmets.
Improvements may be shown by epidemiological or biomechanical evidence.
However, considering the degree of head injury protection provided by
current helmets, incremental improvement would be difficult to detect,
even with a large epidemiological study.
---------------------------------------------------------------------------
\13\ Myers, Barry, M.D., Ph.D. ``An Evaluation of A Helmet
Standard for Children,'' Report to the U.S. Consumer Product Safety
Commission (July 1997).
---------------------------------------------------------------------------
From a biomechanical perspective, it is important to assess how
changes in test headform mass and peak-g criteria would affect helmet
design and protective capability. This can be done by examining how a
helmet functions to protect the head in an impact.
The helmet has a crushable liner typically made of expanded
polystyrene foam. If the liner is crushed as the head presses against
the inside of the helmet during impact, the liner allows the head to
stop over a longer distance and time than would otherwise be the case.
This reduces the transfer of energy to the head, thereby reducing the
risk of injury.
The degree to which the liner resists being crushed also affects
the helmet's protective qualities. For a given impact, a helmet liner
that is too soft will ``bottom out,'' thereby losing its protective
ability to allow relative movement between the head and the object
being impacted. Conversely, a liner that is too hard will not allow
sufficient crushing to adequately protect the head.
Proponents of special provisions for young children's helmets
believe that these helmets should be tested under different test
parameters than helmets intended for older persons. The current test
parameters are based primarily on adult head injury tolerance and on a
headform mass that is approximately that of an adult head. Supporters
of special provisions contend that these adult test parameters result
in a helmet with a liner that is too stiff to optimally protect a young
child's head. By using a headform weight that better represents a young
child's head (e.g., 3.9 kg), and reducing the allowable peak-g, helmets
would need to be designed with a lower density (``less stiff'') liner
to further lessen the impact transmitted to the head.
A simple way to examine the effect of changing headform mass and
the peak-g criterion is to model the helmet as a spring and apply the
one-dimensional spring-mass impact formulas shown below. This approach
is discussed by both Dr. Myers and by Mr. Jim Sundahl, Senior Engineer
with Bell Sports, in his response to the proposed rule [12].
[GRAPHIC] [TIFF OMITTED] TR10MR98.000
Where:
apeak = peak acceleration (peak-g)
Vo = impact velocity
k = liner stiffness
m = headform mass
xpeak = required stopping distance (liner thickness)
If the value for headform mass m is reduced in Equation (1), the
value for liner stiffness k must be reduced to achieve the same peak-g
at the same impact velocity. This means that if a helmet that meets the
standard's criteria with a 5-kg headform did not meet the peak-g
requirement using a lighter headform, the helmet liner would need to be
made softer so more crushing of the liner could occur.
If the value for peak acceleration apeak is reduced in
Equation (1), and the other variables are held constant, the value for
liner stiffness k again must be reduced. Thus, a helmet that could not
comply with a reduced peak-g criterion also would need a softer liner
to allow more crushing. Equation (2) shows that, with a decreased liner
stiffness, a greater percentage of the available crush distance will be
used during impact.
The biomechanical analysis shows that, for impact conditions that
do not result in complete compression of the
[[Page 11719]]
helmet's liner, it is possible to lessen the impact energy transmitted
to the head (and reduce the risk of injury) by reducing the stiffness
of the liner. However as the impact energy increases, a helmet with a
softer liner will bottom out (crush beyond its protective capacity)
under less severe conditions than a helmet with a more rigid liner of
the same thickness. To compensate, the softer helmet would have to be
made thicker to prevent bottoming out. However, there is a limit to how
thick a helmet can be before it is no longer practical or appealing to
the user. Therefore, the goal of helmet design is to optimize liner
density and thickness to protect against the widest range of impact
conditions and still have a product people will use.
The biomechanical analysis suggests that reducing the liner
stiffness could have both a positive and a negative influence on the
protection provided by helmets under existing criteria. Therefore, it
is necessary to also examine available epidemiological data that relate
to this issue. Decreasing the liner stiffness would benefit those who
experience injuries with minimal or no liner deformation of current
helmets. However, a decrease in liner stiffness could increase the
number of head injuries that occur during more severe impacts that
cause the helmet liner to bottom out.
To learn the effect on the level of protection offered by softer
helmet liners for children under 5, two questions would need to be
answered:
1. Are children suffering head injuries with minimal or no
deformation of current helmet liners?
2. Are children suffering head injuries with a bottomed-out liner?
Unfortunately, currently available information does not answer
either of these questions. Therefore, it is uncertain whether young
children would benefit from special provisions for headform mass and
peak-g.
The only known study to examine the relationship between helmet
damage and head injury was completed in 1996 by the Snell Memorial
Foundation and the Harborview Injury Prevention and Research
Center.14 Of those bicycle helmets collected from
individuals (of various ages) who went to a hospital, 40% of the
helmets had no deformation, 14% had significant damage in which the
helmet was approaching a bottomed-out condition, and 7% of the helmets
had catastrophic damage. The data were not presented specifically for
the under-5 age group or any other specific age group. The study showed
that there was a risk of head and brain injury even with no or minimal
helmet damage. The risk of injury increased moderately as the severity
of helmet damage increased, until catastrophic damage was reached. As
expected, the risk of head and brain injury jumped dramatically when a
helmet was damaged catastrophically. This study suggests that if
helmets for all ages were designed with softer liners, there is a
potential to both improve the protection for lower-severity impacts and
increase the risk of injury at the higher-severity impacts.
---------------------------------------------------------------------------
\14\ Rivara, Frederick P., MD, MPH, Thompson, Diane C., MS,
Thompson, Robert S., MD ``Circumstances and Severity of Bicycle
Injuries,'' Snell Memorial Foundation/Harborview Injury Prevention
and Research Center (1996).
---------------------------------------------------------------------------
Since the risk of injury rises dramatically with catastrophic
helmet damage, and current helmets are effective in reducing the risk
of head and brain injuries, it would be imprudent to require softer
helmet liners for bicyclists of all ages. The available data are
insufficient to determine that such a change would increase overall
protection. When focusing on the age range of under 5 years, currently
available information is even more sparse. Therefore, if helmets for
children under age 5 were made with softer liners, there are
insufficient data to estimate either (1) the level of protection that
might be gained at the lower-severity impacts or (2) the protection
that might be lost at the severe impact conditions that completely
crush the liner.
For the reasons discussed above, the Commission did not include
special provisions in the final standard for headform mass and peak-g
criteria for young children's helmets. There are insufficient data to
justify the changes, and these changes could provide less protection in
the most serious impacts. However, should future studies provide
evidence that young children, or bicyclists of any age, could benefit
from decreased liner stiffness, the Commission could consider revisions
to the bicycle helmet standard at that time.
8. Impact Attenuation Test Rig
a. Type of Test Rig
The originally proposed CPSC standard and the current interim
mandatory standards allowed the use of either a wire- or rail-guided
impact test rig. In the revised proposal, the Commission specified only
the monorail test rig, to avoid the possibility that different results
would be obtained with the two types of test rigs.
Some helmet manufacturers [5, 29, 30], and the Snell Memorial
Foundation [28], disagreed with the specification of the monorail type
of impact test rig. Commenters stated that guidewire rigs were more
widely used in the industry. Some commenters claimed that since there
is no evidence that directly correlates monorail with guidewire rig
results, many firms would be forced to buy monorail rigs to address
liability concerns. Trek [5] stated that the burden of this expense may
require additional analysis of the financial impact to small business,
as required by the Regulatory Flexibility Act. Snell wrote that
guidewire rigs have proven reliable, efficient, and highly repeatable.
They are less expensive to install than monorail devices, and they are
easier to maintain. Snell stated that there is no demonstrated
improvement associated with the monorail rig in testing reliability and
capability. Most commenters suggested that the Commission allow both
monorail and guidewire rigs.
To respond to this issue, the CPSC's staff initiated a seven-
laboratory comparison test program. The main purpose of the study was
to determine if there are statistically significant mean differences in
test results when using monorail and guidewire test rigs under
standardized testing conditions.
Seven laboratories participated in the test program, including the
CPSC lab. Five of the laboratories tested on both monorail and
guidewire rigs. Two laboratories only tested on monorail rigs. Three
different helmet models were used. Each helmet was impacted twice, once
at the rear of the helmet and once near the crown. Tests were conducted
using flat and curbstone anvils, and all testing was performed with
ambient-conditioned helmets. This experiment allowed the analysis of
the effect of the following variables: rig type, anvil type, helmet
model, laboratory, anvil impact sequence, and impact location.
The statistical analysis of the interlaboratory results showed that
for the majority of variable combinations, the choice of test rig did
not have an appreciable effect on test results. However, on the Model I
helmets, and only when the second impact was on the curbstone anvil,
the monorail showed a significantly higher mean logarithm for peak-g
readings summed across laboratories having both types of test rigs. For
reasons completely unrelated to these test results, a curbstone impact
in combination with another impact on any single test helmet is no
longer permitted in the final standard. Since the interlaboratory data
(summed across the laboratories that used both types of test rigs) show
no significant differences between guidewire and monorail rigs under
test conditions within those allowed in the
[[Page 11720]]
final standard, the standard allows either type of rig to be used for
impact attenuation testing.
Over the last 15-20 years, voluntary standards in the U.S. have
allowed both monorail and guidewire types of test rigs. Both types of
test rigs have been used extensively in independent test laboratories
and in manufacturers' in-house test facilities. The Snell Memorial
Foundation, one of the established helmet test organizations in the
U.S., uses guidewire rigs to test conformance to their standards. The
Commission has no evidence that the allowance of both types of test
rigs in voluntary standards has resulted in a compromise of safety for
bicycle helmet users.
For the reasons discussed above, the Commission concludes that both
types of rigs are suitable for impact attenuation testing. Therefore,
the final CPSC standard specifies that either a monorail or a guidewire
test rig may be used.
b. Accuracy Check
After evaluating the results of the multi-lab testing, the
Commission concluded that the instrument system check procedure should
include a procedure for calibrating the accuracy of a test rig.
Therefore, the final rule includes a precision and accuracy procedure,
so that laboratories can verify that their test equipment is recording
accurately. The procedure requires that an aluminum sphere (spherical
impactor) of a specified dimension be dropped with a certain impact
velocity onto a Modular Elastomer Programmer (MEP). A MEP is a
cylindrical pad of polyurethane rubber that is used as a consistent
impact medium for the systems check procedure. Pre-test and post-test
impacts on an MEP to verify system recording is a standard practice of
bicycle helmet test labs. All recorded impacts must fall within the
range of 380 g to 425 g. In addition, the difference between the high
and low values of the three recorded impacts must not be greater than
20 g.
The range of 380 g to 425 g represents an allowable tolerance of
about 10%. The interlaboratory testing showed this tolerance to be
attainable between laboratories. However, test experience shows that
even greater precision can be obtained for the systems check procedure
within a given laboratory. The test data from the interlaboratory study
show that a target range of 380 g to 425 g and a precision range of 20
g can be achieved.
c. Test Headform Characteristics
SwRI [#2] suggested that a more appropriate value for the lower
limit on the resonant frequency of the headform material should be 2000
hz instead of 3000 hz.
The important conditions for the test headforms are the material
specification and the dimensions defined by the draft ISO/DIS 6220-1983
standard.\15\ This goal is accomplished by stating that the headforms
shall be rigid and be constructed of K-1A magnesium alloy. Test
experience shows that headforms meeting this description will not
exhibit resonant frequencies that will interfere with proper data
collection. Therefore, Sec. 1203.9 has been changed to delete reference
to any lower limit on resonance frequencies. The proposal also stated
that another ``functionally equivalent'' metal could be used as the
headform material. This alternative has been eliminated in the final
rule to specify the headform apparatus as precisely as possible and
ensure against the use of materials that may influence the test
results.
---------------------------------------------------------------------------
\15\ Although the draft ISO/DIS 6220-1983 standard was never
adopted as an international standard, it has become a consensus
national standard because all recent major voluntary standards used
in the United States for testing bicycle helmets establish their
headform dimensions by referring to the draft ISO standard.
---------------------------------------------------------------------------
Dr. Richard Snyder, President of the George Snively Research
Foundation [19], referenced two studies that related helmet fit to head
size and shape. The first study was conducted by Dr. Bruce Bradtmiller
of the Anthropometry Research Project, Inc. Dr. Bradtmiller also
responded to the proposed rule [20]. He concluded that, for proper
child-helmet sizing, head breadth and length variables were more
accurate guides than using age or head circumference. Dr. Bradtmiller
urges caution in basing the CPSC's rules for children's helmets on the
draft ISO DIS 6220-1983 standard for test headforms. The study shows
variation in the ratio of head length to head breadth. This ratio was
found to be the prime determinant for helmet fit. The ISO standard,
however, maintains a constant head breadth/length ratio. A second study
also concluded that head circumference was not always a good indicator
for helmet fit.
ISO headforms are the established norm for headgear testing in the
U.S., Canada, Europe, and Australia. No other system of headforms is
currently available that can be shown to prevent more injuries.
Therefore, the Commission is retaining the ISO headform specification
in the final CPSC standard. However, the Commission's staff will stay
current on developments of test procedures and equipment that could
lead to improvements in general helmet fit and in improvements that
make it easier to fit and adjust helmets, especially for children.
d. Alignment of Anvils
The Commission amended Sec. 1203.17(a) to specify that the center
of the anvil must be aligned with the center vertical axis of the
accelerometer. This describes the already standard operating procedure
for bicycle helmet testing and is meant to prevent impacting helmets on
the ``corners'' of anvils.
e. Definition of ``Spherical Impactor''
SwRI [2] suggested that it is more important to specify a 5-kg
combined drop mass for the spherical impactor and the drop assembly
than to specify a 4-kg mass for the impactor itself.
The Commission has adopted this suggestion. The more precise
specifications for a spherical impactor for use as a system check
device are now in Sec. 1203.17(b)(1), under the systems check
procedure.
9. Impact Attenuation Test Procedure
a. Anvil Test Schedule and Use of Curbstone Anvil
Six respondents [5, 12, 27, 29, 30, and 31] submitted comments
requesting changes to the test schedule in Sec. 1203.13 regarding the
use of the curbstone anvil. All of the respondents expressed concern
over using two curbstone impacts on a single helmet. As proposed,
Sec. 1203.3(d) and Table 1203.13 did not define the conditions of the
fourth impact on a helmet. The fourth impact in the proposed standard
was left to the discretion of test personnel, and thus could have been
a second curbstone impact. One of the commenters was also concerned
about impacting the helmet with the curbstone anvil after the helmet
was conditioned in a wet environment [12].
There also was concern about the curbstone footprint overlapping
other impact sites and violating the ``single impact'' principle of
testing [27 and 31]. The length of the curbstone anvil restricts the
location of impact sites that can be used without overlap. The use of a
second curbstone anvil, and the damage caused by curbstone impacts, can
restrict the selection of test sites further, to the point where only
three impacts without overlap may be possible on a small helmet.
The Commission agrees that the previously proposed test schedule
[[Page 11721]]
should be revised to prevent the possibility of striking a test helmet
with more than one curbstone impact. The potential for overlapping
``footprints'' of curbstone impacts combined with other impacts on a
single test helmet goes beyond the intended principle of a single
impact for a given area. The Commission disagrees, however, with those
commenters who recommended that only ambient-conditioned helmets be
subjected to a curbstone impact. To ensure adequate protection against
impact against curbstone-type shapes, tests for that anvil, as well as
the other test anvils, should be carried out in all of the
environmental conditions prescribed by the standard. Accordingly,
revised Sec. 1203.13 and Table 1203.13 contain a revised test schedule
to incorporate a single curbstone impact on each of four ``clean''
helmet samples, one from each of the conditioning environments.
The Commission's staff discovered during testing with the curbstone
anvil that severe physical damage--namely splitting of the helmet from
the impact point to the edge of the helmet--could occur even though the
impact did not exceed the 300 g criterion. This led to consideration of
whether in such cases the curbstone anvil test should be repeated on
another sample to help ensure that other helmets will not fail this
test.
The Commission acknowledges that, when marginal or unusual results
occur in any of the standard's tests, retesting may be appropriate,
even though the 300-g criterion is not exceeded. Other conditions that
may prompt the Commission to undertake verification testing include
(but are not limited to) peak-g readings that are very close to the
300-g failure criterion. However, since the option of additional
testing inherently exists, it is not necessary to include a provision
requiring such retesting in the standard.
b. Definition of ``Comfort Padding''
The proposed definition of comfort padding included the statement:
``This padding has no significant effect on impact attenuation.'' SwRI
[2] commented that fit padding may have some influence on impact
characteristics.
The Commission agrees with this commenter and deleted this
statement from the definition.
c. Testing on More Than One Headform
In the revised proposal, the standard would have tested a helmet on
all sizes of headform on which it fit. ``Fit'' was obtained if it was
not difficult to put the helmet on the headform and the helmet's
comfort or fit padding was partially compressed.
PHMA [29] recommended that the situation where more than one
headform will ``fit'' a helmet should be addressed by specifying the
use of the largest headform that will accommodate the helmet, with
comfort padding adjusted to optimize the fit.
The Commission concludes that it is appropriate to simplify the
test procedure by testing on only one size headform. This is consistent
with the current interim mandatory standards. However, in contrast to
the commenter, the Commission believes that it is more appropriate to
test on the smallest headform that is appropriate for the test sample.
The Commission believes that the smaller headform will represent the
more stringent test condition for the positional stability test.
Testing on only one size headform will lessen the number of test
samples needed to test compliance to the standard.
Therefore, a helmet shall be tested on the smallest of the
headforms appropriate for the helmet sample. This size headform is the
smallest headform on which all of the helmet's sizing pads are
partially compressed when the helmet is equipped with its thickest
sizing pads and positioned correctly on the reference headform.
Bell Sports [12] remarked that, where a helmet will ``fit'' more
than one headform size, choosing the conditioning environment for
testing on the larger headform(s) that produced the highest g-value in
the test on the smallest headform that the helmet fits does not
necessarily provide the worst case. The commenter recommended that
there be four impacts in any conditioning environment chosen by the
test technician. As explained above, the Commission is not going to
test a given size helmet on more than one headform size. Accordingly,
this comment is no longer applicable.
d. Number of Helmets Required for Testing
Four respondents commented on the number of helmets required for
testing when the helmet includes attachments, (e.g., removable visor,
face shield) and possible combinations of attachments [5, 12, 29, and
30]. They expressed concern that the proposed standard requires too
many production helmet samples to be tested. One respondent [12]
offered suggested amending Sec. 1203.7(b) to include the statement that
``Helmets can be tested with any combination of accessories.''
Section 1203.7(a) of the proposed standard requires helmets to be
``tested in the condition in which they are offered for sale.''
Additionally, they are required to pass all tests both with and without
any attachments that may be offered. To adopt the suggested wording
would not maintain the requirement that helmets would meet the standard
with all combinations of accessories. However, the Commission agrees
with these commenters that it may be impractical and unnecessary to
specify an additional set of eight test helmets for each added
attachment and each combination of attachments in order to test for
compliance with the standard.
To address this issue, the Commission decided to specify that
attachments need be tested only when they can affect the test results,
and that even then only a ``worst case'' combination of attachments
need be tested. See the changes to Sec. 1203.7(b) and
Sec. 1203.12(d)(1). For example, in the case of a removable visor that
has no influence on the retention system strength test, it would be
unnecessary to test four helmets (one for each conditioning
environment) to that test with the visor attached and an additional
four helmets without the visor. However, it may be possible for
attachments such as visors or faceshields to influence tests such as
impact attenuation or peripheral vision.
10. Helmet Conditioning
a. Low-Temperature Environment: Temperature Range
SwRI [#2] commented that the allowable temperature range in the
low-temperature environment should parallel the allowable temperature
ranges in the other environments.
The Commission believes it is more important for the low-
temperature environment range to be consistent with the current interim
standards than for the range to parallel the tolerance allowed in the
other environments. Thus, this comment was not adopted. However, the
proposed temperature range contained a typographical error. The range
should have been (-17 to -13 deg.C). This range is consistent with
ANSI, ASTM, Snell 95 and CSA standards. This typographical error has
been corrected.
b. Water-Immersion Environment
Paula Romeo [26] suggested that the water-immersion environment was
unrealistic and recommended a spray conditioning environment.
Commission testing of both immersed and water-sprayed helmets under
various time durations showed no consistent trend in resulting peak
acceleration levels. The immersion environment has the advantages of
[[Page 11722]]
being easier to define and of subjecting the helmet to a uniform
conditioning exposure. Since testing showed that these commenters'
concerns were unfounded, the immersion method of wet-conditioning is
retained.
c. Reconditioning Time
The revised proposed standard provided that a helmet that was
removed from its conditioning environment for more than 3 minutes
before testing would be reconditioned for 5 minutes for each minute
beyond the allotted 3 minutes before testing could be resumed. SwRI [2]
noted that there would be potentially no upper limit to the exposure
time to recondition a helmet once it is removed from the conditioning
environment for more than 3 minutes.
The Commission agrees with this comment and has added a 4-hour
limit to the reconditioning time in Sec. 1203.13(c).
11. Labels
a. Label Format and Content
Two respondents [22, 23] urged the Commission to require ``an
appropriate symbol to appear adjacent to the statement of compliance on
the label'' and to add wording to warn that ``failure to follow the
warnings may result in serious injury or death.''
The Commission agrees that more emphasis should be placed on the
warning labels. Accordingly, the signal word ``WARNING'' is used with
the warnings required by Sec. 1203.6(a)(2)-(5). See Sec. 1203.6(a)(6).
The Commission concludes that the signal word will be more effective
than a symbol, and the limited size of the inside of a helmet, and the
amount of information already required on the labels, prevents the use
of both a signal word and a symbol.
The limited space also prevents using the additional suggested
language ``failure to follow the warnings may result in serious injury
or death.'' In addition, this language could possibly mislead some to
conclude that proper use of a helmet will always prevent serious injury
or death. Accordingly, the Commission is not requiring a warning symbol
or the suggested language that ``failure to follow the warnings may
result in serious injury or death.''
b. Use Label
The proposed standard required a label stating ``Not for Motor
Vehicle Use.'' Some comments addressed this choice of language.
[Comments 11, 13, 22, 26.]
Two commenters stated that ``Not for Motor Vehicle Use'' wrongly
suggested the helmet was appropriate for any use other than motor
vehicles. Another commenter felt that ``Not for Motor Vehicle Use''
allows the helmet to be used for other activities similar to bicycle
riding, where no alternative helmet exists. A fourth commenter argued
that ``For Bicycle Use Only'' was a positive statement to which users
are more likely to respond.
On reconsideration, the Commission concludes that neither the ``Not
for Motor Vehicle Use'' label nor the ``For Bicycle Use Only'' label
adequately conveys the circumstances under which helmets that meet the
CPSC standard are appropriate. It is reasonable to assume that helmets
that are certified to the CPSC standard will also provide head
protection for roller skaters, in-line skaters, and, perhaps, some
other recreational activities. In-line skaters should not be
discouraged from wearing a helmet by a label stating ``For Bicycle Use
Only.''
The Commission also believes that consumers understand both the
differences between bicycle helmets and motorcycle/motorsport helmets
and that bicycle helmets would not provide adequate protection for
motorsport activities. Therefore, the ``Not for Motor Vehicle Use''
label is not a critical safety message that should be mandated in the
CPSC standard. Therefore, the final CPSC standard does not require a
``use'' label, but maintains the requirement for a certification label
that informs the consumer that the helmet is certified to the U.S. CPSC
standard for bicycle helmets.
c. Labeling for Cleaning Products
The second proposal required a label warning the user that the
helmet can be damaged by contact with common substances (such as
certain solvents, cleaners, etc.) and that this damage may not be
visible to the user. This label is also required to state any
recommended cleaning agents and procedures, list any known common
substances that damage the helmet, and warn against contacting the
helmet with these substances.
Several respondents [2, 11, 12, 29] expressed concern that too much
information about cleaning products would be needed on the label and
argued that consumers should be directed to the instruction manual for
the list of cleaning materials.
This label is not intended to list every possible cleaning agent
that can or should not be used on the helmet. Since the consumer may
not always have the owner's manual, a label on the helmet should
provide some general cleaning instructions and warnings. The language
of Sec. 1203.6(a)(5) has been changed to make this intent clear.
d. Warning To Replace After Impact
[Commenters 22, 23, 26.] Some respondents agreed with the proposed
standard's provision that the label on the helmet should advise
consumers to destroy the helmet or return it to the manufacturer if it
is involved in an impact. Others disagreed and requested more guidance
on whether the helmet is impaired before a consumer has to return the
helmet.
The variety of factors (impact surface, impact location on helmet,
impact speed, etc.) that are involved in an impact to a helmet, and the
level of interaction of each factor, are so complex that it is
inappropriate to address them in a label. It is to the consumer's
overall safety benefit to return the helmet to the manufacturer or
destroy and replace it. Accordingly, the proposed replacement warning
is not changed.
e. Durability of Labels
SwRI [2] remarked that a requirement for labels to be likely to
remain legible throughout the life of the helmet cannot be tested and
could lead to differences between laboratories. The PHMA [29] also
expressed concern about this requirement, stating that it was unaware
of any technology that will ensure that a sticker will stand up under 5
years of the type of exposure that a helmet receives.
The Commission shares these commenters' concerns. Current voluntary
bicycle helmet standards require ``durable'' labeling or labeling that
is ``likely to remain legible for the life of the helmet.'' These
conditions are not quantified in current standards. The Commission is
not aware of any existing performance test method that can be applied
in this circumstance. Since a requirement for legibility for the life
of the helmet is vague and possibly unattainable, the Commission has
changed the requirement to require ``durable'' labels.
f. Labels on Both Helmets and Boxes
The American Society of Safety Engineers (``ASSE'') [11] and the
NSKC [22] suggested that ``proper fit'' information should be on both
the helmet and the outside of the box.
The Commission does not believe it is necessary to have the actual
fitting instructions on the box, because there is no information
indicating that such a label would be effective in assuring proper fit.
However, it is important that consumers be aware that helmets do come
in different sizes and that proper
[[Page 11723]]
fit is important. A label on the box promoting the need for proper fit
could inform parents, before they buy the helmet, that they need to
properly fit the helmet to the child. Therefore, the final standard
applies Sec. 1203.6(a)(3) to the helmet's packaging, as well as to the
helmet.
12. Instructions for Fitting Children's Helmets
The NSKC [22] recommended that the proposed fitting instructions to
accompany children's helmets be in age-specific language.
The Commission believes that age-specific instructions are
unnecessary. The proposed standard requires both a graphic
representation of proper positioning and written positioning and
fitting directions. The graphics will reach more children than would
age-specific instructions, because they allow children of all ages to
compare the way their helmet looks with the pictures. In addition,
graphics convey the critical information to non-English-reading
individuals and illiterates. Children and adults are likely to be
better able to understand and appreciate pictures than age-specific
instructions. This is more likely to effectively deliver the message,
allowing both parents and children to become aware of the proper fit.
13. Retention System Strength Test
SwRI [2] asked whether both the peak and residual displacements in
the test of the dynamic strength of the retention system should be
measured in order to better describe the dynamics of the system.
Only the peak deflection reading is needed to determine failure of
the retention system. This is consistent with existing U.S. bicycle
helmet standards. Therefore, no change to the proposed rule was made in
response to this comment.
USC-HPRL [8] suggested that the retention system test
(Sec. 1203.13(d)) be done after impact testing. The commenter reasons
that an accident can damage a helmet and severely compromise the
retention system. The retention system must ensure that the helmet
remain on the head during an accident sequence.
After considering this comment, the Commission decided to make no
changes to the sequence for retention system testing. Testing the
retention system prior to impact testing is consistent with the ASTM
and Snell standards. The Commission has no evidence that the test
sequence in the ASTM and Snell standards allows helmets that do not
have adequate retention systems.
The commenter also recommends that the ``zero'' position for
measuring elongation be established without the proposed step of pre-
tensioning the straps with a 4-kg mass.
There is no evidence that establishing the ``zero'' position after
pretensioning the retention system, as proposed, would allow helmets
that do not have adequate retention systems to pass the test.
Therefore, the Commission made no changes to the procedure for
establishing the pre-test ``zero'' position.
14. Positional Stability Test
SwRI [2] remarked that the ASTM Headgear Subcommittee is
considering a 7-kg preload to set the helmet during testing. SwRI also
asked whether a thin rubber pad should be specified to soften high
frequency impact noise.
Testing to support the development of the positional stability test
was with equipment specified as proposed in the CPSC standard.
Subsequent to initial ASTM discussions about possible revisions to the
proposed test procedure, the ASTM F8 Headgear Subcommittee decided not
to modify the pre-load and not to specify a rubber impact pad.
Therefore, the Commission made no change to this section.
NSKC [22] also recommends that the Commission examine the potential
influence that fitting pads may have on the helmet's ability to comply
with the retention system requirements.
When testing for positional stability, the standard instructs
testers to position and fit the helmet on the test headform according
to the manufacturer's instructions. This procedure may involve changing
the size and position of the fit pads in order to achieve a secure fit.
A similar procedure is followed to fit a bicycle helmet to the user.
Although fitting a helmet to a metal headform will not account for all
of the human elements involved when consumers fit helmets to their
heads, the proposed procedure is the most practical approach at this
time and should help keep the helmet secure during an accident.
Therefore, no change to the proposed standard was made in response to
this comment.
15. Vertical Vision
One commenter on the original proposal suggested that the
Commission adopt requirements for a vertical field of vision. The
Commission declined to do this because it had no information to
indicate that bicycle helmets are posing a risk of injury due to
inadequate upward or downward visual clearance.
In response to the second proposal, SwRI [2] suggested that
requirements for visual clearance at the brow be considered and that
this would be especially important for racers who ride in the crouch
position. However, a brow clearance requirement might, in some cases,
reduce the amount of head coverage in the brow area. Further, CPSC has
no information to indicate that bicycle helmets meeting existing
standards are posing a risk of injury due to inadequate ``upward''
visual clearance. Therefore, the Commission did not add a ``brow''
visual clearance requirement to the final standard.
16. Reflectivity
Some comments on the original proposal related to possible
requirements for helmets to improve a bicyclist's conspicuity in
nighttime conditions. Data do show an increased risk of injury while
bicycling during non-daylight hours. The Commission indicated that it
would study this issue further in conjunction with planned work on
evaluating the bicycle reflector requirements of CPSC's mandatory
requirements for bicycles. 16 CFR part 1512. The Commission stated that
it would decide whether to propose reflectivity requirements for
bicycle helmets under the authority of the Bicycle Helmet Safety Act
after that work is completed.
Several commenters on the revised proposal [1, 7, 11, 13, 16, 17,
22, 23, 24, 26] urged that the Commission not postpone implementing
bicycle helmet reflectivity requirements.
Since the revised proposal, the Commission conducted field testing
on bicycle reflectors and examined the issue of reflectivity on bicycle
helmets. In the field testing, half (24/48) of the subjects were tested
using bicycle riders with reflective helmets and the other half were
tested using riders wearing non-reflective helmets. The reflective tape
used on the helmets met a proposed Standard on use of Retroreflective
Materials on Bicycle Helmets that was balloted by the ASTM Headgear
Subcommittee. The study failed to show that the particular helmet
reflective strip used in the study would increase the distance at which
a bicycle can be detected or recognized (Schroeder, 1997). Accordingly,
the Commission lacks data to support a requirement for bicycle helmet
reflective performance.
17. Hard-shell Requirements
In recommendations to the Commission, Duke University researcher
Barry Myers M.D., Ph.D., suggested that a test for penetration
resistance be considered for the final standard. He reasons that such a
test would require helmets to have hard
[[Page 11724]]
outer shells. Dr. Myers contends that a hard shell will reduce the risk
of penetration-type traumas. He further contends that a hard shell will
lessen friction between the helmet and the impact surface and that this
has two benefits. First, it would reduce the total change in velocity
(V) of the head during impact. Second, by reducing the forces
on the head caused by friction between the helmet and the impact
surface, it would reduce the risk of neck injury.
In support of hard-shell helmets, Dr. Myers references the latest
Harborview 16 study, which reported a ``consistent
suggestion that hard-shell helmets are more protective against head and
brain injuries than non-hard-shell helmets.'' Dr. Myers acknowledges
that the differences measured were not statistically significant.
However, he believes that a larger study, containing a sufficient
number of severe brain injuries, might show this correlation with
statistical significance.
---------------------------------------------------------------------------
\16\ Thompson, Diane C., MS; Rivara, Frederick P, MD, MPH; and
Thompson, Robert S., MD. ``Effectiveness of Bicycle Safety Helmets
in Preventing Head Injuries,'' Journal of the American Medical
Association 276 (December 1996): 1968-1973.
---------------------------------------------------------------------------
In discussing protection against neck injury, Dr. Myers notes that
automotive accidents cause serious neck injuries in about 15 to 25% of
the persons who have serious head injuries, suggesting that neck injury
is common among the most severely brain injured. However, since there
were so few cases with severe brain injuries in Harborview's analysis
of bicycling incidents, the significance of neck injury, and its
mitigation by hard-shell helmets, among the severe brain injured cannot
be determined from the Harborview study.
Although Dr. Myers suggests a penetration test in order to require
that bike helmets have a hard shell, he states that a detailed study of
the most severe injuries is warranted. He also recommends that, before
a requirement that all helmets have a hard shell is adopted, there
should be an evaluation of whether this would reduce the number of
riders who would wear bicycle helmets.
Currently available information does not show a need to address the
hazard of penetration-type head impacts to bicyclists. One study
17 suggests that the majority of helmets involved in bicycle
accidents suffer impacts on flat, hard surfaces (asphalt, cement, etc.)
and that penetration-type impacts are rare.
---------------------------------------------------------------------------
\17\ Dean Fisher and Terry Stern, ``Helmets Work!,'' Bell
Sports, Inc., AAAM/IRCOBI Conference, Lyon, France (September 1994).
---------------------------------------------------------------------------
Regarding the contention that requiring a hard shell may reduce
neck injuries, bicycle-related injury data show a low incidence of
serious neck injuries. In 1996, there were 566,400 bicycle-related
injuries treated in U.S. hospital emergency rooms, based on CPSC data
from NEISS. Of these, about 6,630 (1%) involved the neck. Of the neck
injuries, about 4,520 (68%) involved strains or sprains, 1,155 (17%)
involved contusions or abrasions, 275 (4%) involved lacerations, 240
(4%) involved fractures, and 440 (7%) involved other diagnoses. These
numbers show that neck fractures accounted for about 0.04% of the total
number of emergency-room-treated bicycle-related injuries in 1996.
Detailed information was not available to analyze whether the use of a
helmet or type of helmet had an effect on the risk of neck injury.
The Harborview study also reported a low incidence of neck injury.
Their report showed that 2.7% of the cases (including both helmeted and
non-helmeted cases) suffered neck injury, ranging from sprain to nerve-
cord injuries. There was no correlation between neck injury and helmet
use or helmet type.
Dr. Myers cites that automotive accidents cause serious neck
injuries in about 15 to 25% of the persons who have serious head
injuries. However, this statistic may not be relevant to the issue of
friction between the shell and the impact surface, since the neck
injuries in automotive accidents are not necessarily caused by friction
between the head and an impacting surface.
Dr. Myers' advocacy of hard-shell helmets to reduce friction would
seem to argue for a test to evaluate friction resistance of a helmet
against typical impact surfaces, rather than for a penetration-
resistance test.
One study on this issue was done by Voigt Hodgson, Ph.D., at Wayne
State University.18 In this study, test helmets were secured
to a modified Hybrid III dummy, and skid-type impacts were done on
concrete at various angles from 30 to 60 degrees. Hodgson found that
both hard-shell and micro-shell (or thin-shell) helmets tended to slide
rather than ``hang-up'' on impact with concrete. (Thin-shell helmets
are the type most commonly sold in the current market). No-shell
helmets showed a larger tendency to hang-up on impacts with concrete.
One of the conclusions of the study was that any helmet similar to
those tested in the study (hard-, thin-, or no-shell) will protect the
brain and neck much better than wearing no helmet.
---------------------------------------------------------------------------
\18\ Voigt R. Hodgson, Ph.D., ``Skid Tests on a Select Group of
Bicycle Helmets to Determine Their Head-Neck Protective
Characteristics,'' Department of Neurosurgery, Wayne State
University, Detroit, MI (March 8, 1991).
---------------------------------------------------------------------------
Harborview reports that there was a consistent trend indicating
that hard-shell helmets provided better protection against head and
brain injury than non-hard-shell helmets. However, in order for the
results to be statistically significant, the number of people in the
study would have had to be 11 times greater.
The Commission concludes that the following considerations are
relevant to any possible requirement for hard-shell bicycle helmets:
1. Studies of bicycle helmets damaged in accidents suggest that
penetration-type helmet impacts are rare occurrences. In addition,
bicycle-related injury data suggest a low incidence of serious neck
injuries. For the small portion of incidents that involve serious neck
injury or penetration-type hazards, available information is
insufficient to estimate the degree of improved protective performance
that hard-shell helmets may offer over non-hard-shell helmets.
2. Non-hard-shell bicycle helmets are effective in preventing
serious head and brain injuries. There are no known studies that report
a statistically significant finding that hard-shell helmets offer
better protection than non-hard-shell helmets.
3. A standard applying to all bicycle helmets has to balance the
protective benefit that might be provided by a hard shell against the
additional cost, weight, bulk, and discomfort caused by such a
requirement. Such undesirable qualities may discourage some users from
wearing helmets, which could more than cancel the effects of any
additional protective qualities. This is an especially important
consideration, given the popularity of non-hard-shell bicycle helmets.
After considering these factors, the Commission concludes that the
available information does not support including a penetration test, or
any other test that would require all bike helmets to have a hard
shell, in the final rule.
D. Certification Testing and Labeling
1. General
Section 14(a) of the CPSA, 15 U.S.C. 2063(a), requires that every
manufacturer (including importers) and private labeler of a product
that is subject to a consumer product safety standard issue a
certificate that the product conforms to the applicable standard, and
to base that certificate either on a test of each product or on a
[[Page 11725]]
``reasonable testing program.'' Regulations implementing these
certification requirements are codified in Subpart B of the Safety
Standard for Bicycle Helmets.
2. The Certification Rule
The proposed certification rule would require manufacturers of
bicycle helmets that are manufactured after the final standard becomes
effective to affix permanent labels to the helmets stating that the
helmet complies with the applicable U.S. CPSC standard. These labels
would be the ``certificates of compliance,'' as that term is used in
Sec. 14(a) of the CPSA.
In some instances, the label on the bicycle helmet may not be
immediately visible to the ultimate purchaser of the helmet prior to
purchase because of packaging or other marketing practices. In those
cases, the final rule requires an identical second label on the
helmet's package or, if the package is not visible--as when the item is
sold from a catalog, for example--on the promotional material used in
connection with the sale of the bicycle helmet.
The certification label also contains the name, address, and
telephone number of the manufacturer or importer, and identifies the
production lot and the month and year the product was manufactured.
Some of the required information may be in code.
The certification rule requires each manufacturer or importer to
conduct a reasonable testing program to demonstrate that its bicycle
helmets comply with the standard. This reasonable testing program may
be defined by the manufacturer or importer, but must include either the
tests prescribed in the standard or any other reasonable test
procedures that assure compliance with the standard.
The certification rule provides that the required testing program
will test bicycle helmets sampled from each production lot so that
there is a reasonable assurance that, if the bicycle helmets selected
for testing meet the standard, all bicycle helmets in the lot will meet
the standard.
The rule provides that bicycle helmet importers may rely in good
faith on the foreign manufacturer's certificate of compliance, provided
that a reasonable testing program has been performed by or for the
foreign manufacturer and the importer is a U.S. resident or has a
resident agent in the U.S.
3. Reasonable Testing Program
Proposed Sec. 1203.33(b)(4) stated that if the reasonable testing
program ``shows that a bicycle helmet may not comply with one or more
requirements of the standard, no bicycle helmet in the production lot
can be certified as complying until all noncomplying helmets in the lot
have been identified and destroyed or altered * * * to make them
conform to the standard.'' Trek USA [5] commented that the proposed
language describing a reasonable testing program was restrictive
because it implies that if a single helmet fails any aspect of the test
procedure, all of the product in the lot cannot be certified until
corrective action is taken. The commenter suggested a change in the
wording of Sec. 1203.33(b)(4) from ``a bicycle helmet'' to ``any
bicycle helmet'' that fails to conform to the testing criteria. The
commenter asserts that this change would provide more flexibility, as
it would remove the possibility of an anomaly in the testing causing a
lack of certification of an entire lot.
The Commission did not make the requested change in the wording of
Sec. 1203.33(b)(4). First, it does not appear that the requested
language would change the meaning of this requirement. Second, the
purpose of the testing program is to detect possible failures of
bicycle helmets in a production lot and to reasonably ensure that the
helmets that are certified comply with the standard. The Commission
intends that failure of one helmet would trigger an investigation to
determine whether the failure extends to other helmets in the
production lot. That investigation should continue until it is
reasonably likely that no noncomplying helmets remain in the production
lot. The wording of Sec. 1203.33(b)(4) has been changed to make this
intent clear.
a. Changes in Materials or Vendors
The proposed standard provides that when there are changes in
parts, suppliers, or production methods, a new production lot should be
established for the purposes of certification testing. The PHMA [29]
wants clarification of when there are material or vendor changes. PHMA
requests that the Commission use the Safety Equipment Institute
(``SEI'') guidance to help firms understand the terms material changes,
design changes, and vendor changes.
The Commission does not think that establishing definitions as
stated in the SEI ``Definition of Term'' would add any significant
clarification for the industry as a whole. Each firm can institute its
own testing program, as long as the testing program is reasonable. The
intent of the regulation is to ensure that all firms establish a
reasonable testing program and to provide flexibility for both large
and small firms. Each firm has the flexibility to define its own terms
in its quality control program, including material changes, design
changes, and vendor changes, as long as the testing program is
effective and reasonably able to determine whether all bicycle helmets
comply with the standard. The Commission made no revision to the
proposed rule in response to this comment. However, manufacturers and
importers should keep records describing the testing program and
explaining why the program is sufficient to reasonably determine that
all of the firm's bicycle helmets comply with the standard. Similarly,
when the testing program detects noncomplying helmets, the firm should
record the actions taken and why those actions are sufficient to
reasonably ensure that no noncomplying helmets remain in the production
lot. See Subpart C of Part 1203.
b. Pre-market Clearance and Market Surveillance
The Snell Memorial Foundation [28] and Paul H. Appel [25] propose
the adoption of the pre-market clearance and market surveillance
provisions of the Snell standard to ensure that quality bicycle helmets
are produced. According to the commenters, without these two Snell
provisions, Government efforts will be insufficient to keep inadequate
helmets off the market.
All firms must ensure that bicycle helmets sold in the United
States are certified to the mandatory bicycle helmet standard, and that
the certifications are based on reasonable testing programs. Firms that
distribute noncomplying products are subject to various Commission
enforcement actions. These actions include recall, injunctions, seizure
of the product, and civil or criminal penalties. The penalties for such
violations could subject a firm to penalties of up to $1.5 million and,
after notice of noncompliance, fines of up to $50,000 or imprisonment
of individuals for not more than 1 year, or both.
The Commission has statutory authority to inspect manufacturers,
importers, distributors, and retailers of bicycle helmets. This
authority includes the right to review and copy records relevant to
compliance with the bicycle helmet standard. The Commission may also
collect samples of bicycle helmets for testing to the standard.
The Commission has a vigorous enforcement program that includes
joint import surveillance with U.S. Customs and compliance surveillance
of domestic producers, distributors, and retailers. In addition, the
staff responds
[[Page 11726]]
to all reports of noncompliance with all mandatory standards.
From previous history with other regulations that the Commission
enforces, compliance with the various CPSC standards is high. In
addition, all firms have a responsibility to report noncompliance with
the standard under Section 15(b) of the Consumer Product Safety Act. 15
U.S.C. 2064(b). Failure to report could subject a firm to severe
penalties.
Based on these considerations, the agency's enforcement programs
and enforcement authority will provide substantial assurance that
bicycle helmets will meet the requirements for the mandatory standard.
Experience in enforcing other CPSC regulations has shown that a high
degree of compliance can be achieved without manufacturers using a pre-
market clearance program or a third-party certifying organization.
Therefore, the Commission made no revision to the proposed rule in
response to this comment.
4. Certificate of Compliance
a. Coding of Date of Manufacture
The proposed standard required the certification label to contain
the month and year of manufacture, but allowed this information to be
in code. Mr. L.E. Oldendorf, P.E., from ASSE[11], the Bicycle Helmet
Safety Institute (``BHSI'') [16], the Bicycle Federation of Wisconsin
[24], and Paula Romeo [26] opposed allowing manufacturers to code the
month and year of manufacture. These commenters felt that uncoded dates
would help consumers determine whether their helmet was subject to a
recall. One commenter stated that an uncoded production date is
necessary to assist consumers when they wish to replace their helmet
after 5 years.
As the commenters noted, an uncoded manufacture date would make it
easier for consumers to tell when their helmets are subject to a
recall. This information also would help users determine when the
helmet's useful life is over and the helmet should be replaced. Snell
helmet standards require that the manufacture date be uncoded, and it
is already a common practice in the industry. Accordingly, the
Commission has revised the standard to require an uncoded date of
manufacture.
b. Telephone Number on Label
Two commenters [23 and 26] urged that the Commission require labels
showing the manufacturer's telephone number. They stated that this
requirement would make it easier for the consumer to contact the
manufacturer about recall information and about instructions for
returning the helmet to the manufacturer after it has been damaged.
The telephone number would be helpful for consumers during a recall
or to inquire about a damaged bicycle helmet because they could
determine the status of their helmets quicker than by a written
inquiry. Obtaining a quicker response would enable the consumer to
replace a defective helmet sooner and thus reduce the possibility of
injuries caused by having an accident while wearing a defective helmet.
Therefore, the Commission is requiring the telephone number of the U.S.
manufacturer or importer on the helmet's labeling.
c. Certification Label on Children's Helmets
PHMA [29] suggested that a label showing certification for children
under 5 is needed on the packaging, but is not needed inside the
helmet.
The Commission does not agree. Since helmets for small children are
likely to be shared with or passed on to multiple users, the sticker on
the helmet is likely to be the only source of information available to
the second or third user. Further, it is common to display helmets at
retail without the box. Thus, the purchaser may not see the box until
after selecting the model, if at all. Therefore, this labeling will be
required on both the box and the helmet.
d. Minimum Age on Labels for Children's Helmets
Section 14(a) of the CPSA requires that certifying firms issue a
certificate certifying that the product conforms to all applicable
consumer product safety standards. 15 U.S.C. 2063(a). Accordingly, the
original proposal would have required the label statement ``Complies
with CPSC Safety Standard for Bicycle Helmets (16 CFR part 1203)''.
This was changed in the revised proposal because the Commission wanted
to guard against the possibility that small adult helmets will be
purchased for children. Therefore, the revised proposed standard
required that helmets that do not comply with the requirements for
young children's helmets would be labeled ``Complies with CPSC Safety
Standard for Bicycle Helmets for Adults and Children Age 5 and Older
(16 CFR 1203)''. Under that proposal, helmets intended for children 4
years of age and younger would bear a label stating ``Complies with
CPSC Safety Standard for Bicycle Helmets for Children Under 5 Years (16
CFR 1203)''. That proposal further provided that helmets that comply
with both standards could be labeled ``Complies with the CPSC Safety
Standard for Bicycle Helmets for Persons of All Ages'', or equivalent
language.
Maurice Keenan, MD, from the American Academy of Pediatrics [21],
requested that a minimum age of 1 year be reflected on the label for
helmets intended for children under age 5. This would better convey the
message that infants (children under age 1) should not be passengers on
a bicycle under any circumstance.
The Commission agrees with the commenter that children under 1 year
of age should not be on bicycles. Children are just learning to sit
unsupported at about 9 months of age. Until this age, infants have not
developed sufficient bone mass and muscle tone to enable them to sit
unsupported with their backs straight. Pediatricians advise against
having infants sitting in a slumped or curled position for prolonged
periods. This position may even be exacerbated by the added weight of a
bicycle helmet on the infant's head. Because pediatricians recommend
against having children under age 1 as passengers on bicycles, the
Commission does not want the certification label to imply that children
under age 1 can ride safely. Thus, the proposed language that a helmet
complies with CPSC's standard ``for Children Under 5 Years'' or ``for
persons of all ages'' is not suitable, since these phrases include
children less than 1 year old.
Further, the only difference between the final requirements for
helmets for children of ages 1-4 and for helmets for older persons is
that the young children's helmets cover more of the head. Therefore,
children's helmets will inherently comply with the requirements for
helmets for older persons, and the label need not indicate an upper
cutoff of age 5 for meeting CPSC's requirements.
For the reasons given above, the proposed label indicating that
helmets comply with the standard for helmets for children under 5 years
has been amended to state that the helmets comply with the CPSC
standard for ``persons age 1 and older.''
e. Identifying the Commission
The NSKC [22] encouraged the Commission to modify the certification
labeling to require the language ``United States Consumer Product
Safety Commission'' rather than ``CPSC.'' The commenter believes that
the acronym is likely to lead to consumer confusion, but that the use
of the full name of the Commission will clearly identify the
[[Page 11727]]
helmet as meeting a federal safety standard.
The rationale presented by the commenter for using the full name of
the Commission instead of using the acronym is logical. However, the
use of the Commission's full name may be impractical for some
manufacturers. The amount of space available on the inside of a helmet
is limited. The proposed regulation requires a number of labels, and
each one is supposed to be legible and easily visible to the user.
Allowing the use of the acronym is a necessary compromise so that all
the labels can be accommodated on the inside of the helmet. However,
the Commission concluded that the acronym should include the
designation ``U.S.'' before ``CPSC'' to indicate that the standard is
issued by an agency of the Federal Government. Further, the Commission
believes manufacturers should have the choice of whether to use the
acronym or spell out the agency's name. Accordingly, the following
wording has been added to Secs. 1203.34(b)(1) and 1203.34(d): ``this
label may spell out `U.S. Consumer Product Safety Commission' instead
of `U.S. CPSC'.''
f. Certification Label on Packaging
The proposed standard provided that the certification compliance
label shall also be on the helmets' packaging or promotional material
if the label is not immediately visible on the product. NSKC [22]
requested that the final standard require that such package label be
legible and prominent, and placed on the main display panel of the
packaging so that it is easily visible to the purchaser.
The Commission agrees with the commenter and has added the
following wording to Sec. 1203.34(d): ``The label shall be legible,
readily visible, and placed on the main display panel of the packaging
or, if the packaging is not visible before purchase (e.g., catalog
sales), on the promotional material used with the sale of the bicycle
helmet.''
E. Recordkeeping
1. Introduction
Section 16(b) of the CPSA requires that:
Every person who is a manufacturer, private labeler, or
distributor of a consumer product shall establish and maintain such
records, make such reports, and provide such information as the
Commission may reasonably require for the purposes of implementing
this Act, or to determine compliance with rules or orders prescribed
under this Act.
15 U.S.C. 2065(b)
The rule requires every entity issuing certificates of compliance
for bicycle helmets to maintain records that show the certificates are
based on a reasonable testing program. These records were proposed to
be maintained for a period of at least 3 years from the date of
certification of the last bicycle helmet in each production lot and to
be available to any designated officer or employee of the Commission
upon request in accordance with Sec. 16(b) of the CPSA, 15 U.S.C.
2065(b).
2. Location of Test Records
The original proposal required that records be kept by the importer
in the U.S. to allow inspection by CPSC staff within 48 hours of a
request by an employee of the Commission. In response to a comment on
the original proposal, the Commission revised the regulation to state
that if the importer can provide the records to the CPSC staff within
the 48-hour time period, the records will be considered kept in the
U.S.
SwRI [2] commented that the 48-hour allowance to provide test
records to the Commission should apply to all manufacturers or
importers, whether or not the test records are maintained within the
U.S.
The Commission agrees with this comment, and the final rule
provides that all firms are required to provide records for immediate
inspection and copying upon request by a Commission employee. If the
records are not physically available during the inspection because they
are maintained at another location, the firm must provide them to the
staff within 48 hours.
3. Length of Records Retention
Paula Romeo [26] raised the issue of whether certification records
should be maintained for longer than 3 years, since helmets can be used
for 5 years.
The purpose of records being kept for 3 years is to ensure that the
helmets have time to clear the distribution channels and get into the
marketplace. If there is a compliance problem or defect in the helmets,
3 years would be sufficient to uncover any problems with the helmets.
The Commission's staff would have time to obtain the records to review
the firm's testing program and take any necessary enforcement action
during this 3-year period. Therefore, no change was made in the rule in
response to this comment.
F. Regulatory Flexibility Act Certification
Introduction
When an agency undertakes a rulemaking proceeding, the Regulatory
Flexibility Act, 5 U.S.C. 601 et seq., generally requires the agency to
prepare initial and final regulatory flexibility analyses describing
the impact of the rule on small businesses and other small entities.
The purpose of the Regulatory Flexibility Act, as stated in
Sec. 2(b) (5 U.S.C. 602 note), is to require agencies, consistent with
their objectives, to fit the requirements of regulations to the scale
of the businesses, organizations, and governmental jurisdictions
subject to the regulations. The Regulatory Flexibility Act provides
that an agency is not required to prepare a regulatory flexibility
analysis if the head of an agency certifies that the rule will not have
a significant economic impact on a substantial number of small
entities. 5 U.S.C. 605.
The Commission's Previous Economic Findings
In the August 1994 notice of proposed rulemaking, the Commission
noted that any costs associated with design changes to comply with the
original proposal would be spread out over the course of production,
and would be small on a per-unit basis. Costs associated with testing
and monitoring were not expected to increase, since the vast majority
of firms already used third parties to test for conformance to the
voluntary standards. The proposal also allowed for self-certification
and self-monitoring which, for some companies, may be substantially
less costly than third-party certification. The proposed labeling
requirements were not expected to have a significant impact on small
firms, in that virtually all helmets already bore a similar label.
Based on this information, the Commission preliminarily concluded that
the proposal would not have a significant impact on a substantial
number of small entities. The Commission received no public comment on
this conclusion.
As a result of non-economic comments of a technical nature, the
Commission proposed a revised standard on December 6, 1995. In that
notice, the Commission reiterated its assessment of the economic impact
of the standard on small businesses. In the preamble to the 1995
proposal, the Commission again preliminarily certified that the
proposed standard, if promulgated, would not have a significant
economic effect on a substantial number of small entities.
Current Economic Assessment and Response to Comments
The Commission's Directorate for Economics prepared an economic
assessment of the safety standard for
[[Page 11728]]
bicycle helmets. The vast majority of helmets now sold conform to one
(or more) of three existing voluntary standards. Many of these helmets
probably already comply with the impact attenuation requirements of the
new rule. On a per-unit basis, costs associated with redesign and
testing are expected to be small.
The standard's labeling requirements are unlikely to have a
significant impact on firms, since virtually all bicycle helmets now
bear a permanent label on their inside surface. Industry sources report
that, given sufficient lead time to modify these labels, any increased
cost of labeling would be insignificant.
The vast majority of manufacturers now use third-party testing and
monitoring for product liability reasons, and are likely to continue to
do so in the future. The standard allows for self-certification and
self-monitoring, however, which is substantially less costly than
third-party testing and monitoring.
The Commission received two comments on the 1995 proposal that
related to the economic effects of the revision. These involved the
cost associated with the specification of a monorail test device, and
the effect of the curbstone testing procedure.
A comment from Trek Bicycle Corporation [5] approved specifying a
single test apparatus, but was concerned that the Commission chose a
monorail-guided test rig over a guidewire unit. Trek said that the
majority of PHMA members test on wire-guided equipment and that some
firms may be forced to purchase monorail units to eliminate product
liability concerns. The firm stated, ``[t]he burden of this unnecessary
expense may provide need for additional analysis of the financial
impact to small business, as required by the Regulatory Flexibility
Act.''
Based on contacts with industry and testing facilities, it appears
that, of those manufacturers that have in-house test labs, an estimated
5 to 10 have only a wire-guided rig. Most commercial, independent, and
academic bicycle helmet test labs have a monorail test rig, and many of
those labs also have one or more wire-guided rigs. The estimated cost
to purchase a monorail-guided rig is about $20,000.
An interlaboratory study comparing the results of monorail and
guidewire test rigs showed no significant differences between the two
types of rigs in test conditions that are within the parameters
permitted by the draft standard. Therefore, the final standard has been
revised to specify that either a monorail or a guidewire apparatus may
be used to test a helmet's impact attenuation performance.
Consequently, the potential cost considerations for laboratories using
guidewire rigs no longer apply.
Another commenter, Bell Sports [12], noted that the proposal also
included impact testing requirements that allowed two impacts with a
device simulating helmet contact with a curb. Bell estimated that
``[t]he addition of the curbstone anvil * * * and with the option of
using it twice on any helmet might well increase the retail price of
bicycle helmets by $2.00 to $10.00.''
The standard is intended to address helmet safety from a single
impact on a given area. For this reason, the impact testing requirement
has been changed to require only a single curbstone impact simulation
test per helmet test sample. Consequently, the potential changes in
helmet design that could have been needed to comply with two curbstone
impact tests no longer apply.
Small Business Effects
Of the 30 current manufacturers of bicycle helmets, all but two
would be considered small businesses under Small Business
Administration employment criteria (less than 100 employees). As the
Commission found previously, the one-time costs of design are expected
to be small on a per-unit basis.
Spokesmen for the PHMA estimate that there are 1,000 to 1,500
bicycle-helmet molds in current use, each of which contains 4 molding
cavities. Redesign may be required for one or more cavities in some
molds, while other molds may not require any cavity redesign. Using a
midpoint estimate of 1,250 molds, there would be some 5,000 cavities in
current use in helmet molds.
The PHMA estimates that the top 4 manufacturers of bicycle helmets
account for about 700 molds (or some 2,800 cavities) used in helmet
production. The other 26 firms account for the remainder or, on
average, 21 molds per firm (84 cavities). The PHMA estimates that 10%
or less of the existing cavities would require redesign in order for
the helmets made by them to comply with the standard. Thus, smaller
firms may need to redesign an average of 8.4 cavities. Each cavity
costs approximately $2,500, according to the trade association. On
average, the one-time cost of cavity redesign for the smaller 26 firms
would be about $21,000 each.
The top 4 firms account for an estimated 75% of the 9 million
helmets sold annually, according to PHMA. The remaining firms thus
account for 25%, or 2.25 million helmets annually. If sales are
allocated uniformly, each of the 26 firms would account for about
87,000 units. If spread over a single year's production, the average
cavity redesign cost would be about 24 cents per helmet.
Further, the industry routinely replaces molds (and, thus,
cavities), either because of style changes in helmet designs or because
they wear out. The above estimates, however, assume that no molds would
have been replaced absent the standard. Because the standard will not
become effective until 1 year after the final rule is published, some
of the noncomplying cavities may be replaced in that interim for
reasons independent of the final standard. Consequently, the estimated
one-time costs associated with the replacement of the smaller firms'
mold cavities that would be attributed solely to the standard are
likely to be significantly less than $21,000 each.
Regulatory Flexibility Certification
Because the per-unit costs of modifying production molds will be
relatively low, the Commission concludes that the rule will not have a
significant impact on a substantial number of small entities.
G. Environmental Considerations
Pursuant to the National Environmental Policy Act, and in
accordance with the Council on Environmental Quality regulations and
CPSC procedures for environmental review, the Commission assessed the
possible environmental effects associated with the safety standard for
bicycle helmets.
The Commission's regulations, at 16 CFR 1021.5(c) (1) and (2),
state that safety standards and product labeling or certification rules
for consumer products normally have little or no potential for
affecting the human environment. The analysis of the potential impact
of this rule indicates that the rule is not expected to affect
preexisting packaging or materials of construction now used by
manufacturers. Existing inventories of finished products would not be
rendered unusable, since Sec. 9(g)(1) of the CPSA provides that
standards apply only to products manufactured after the effective date.
Changes in coverage areas for helmets may require modification or
replacement of existing injection molds. Industry experts estimate that
there are some 1,000 to 1,500 molds currently used by bicycle helmet
producers, and that perhaps 10% are likely to be affected by the
proposed standard. Molds are constructed of aluminum, commonly weighing
40-50 pounds each. Molds are also routinely replaced
[[Page 11729]]
due to wear or to changes in style. Helmet manufacturers send these
older molds back to the firm making replacements, and the older units
are melted down for use in the replacement molds. Thus, the quantity of
discards resulting from the rule is likely to be small.
Especially in view of the statutory 1-year effective date, it is
unlikely that significant stocks of current labels will require
disposal.
The requirements of the standard are not expected to have a
significant effect on the materials used in production or packaging, or
on the amount of materials discarded due to the regulation. Therefore,
no significant environmental effects are expected from this rule.
Accordingly, neither an environmental assessment nor an environmental
impact statement is required.
H. Paperwork Reduction Act
As noted above, U.S. manufacturers and importers of bicycle helmets
will be required to conduct a reasonable testing program to ensure
their products comply with the standard. They will also be required to
keep records of such testing so that the Commission's staff can verify
that the testing was conducted properly. This will enable the staff to
obtain information indicating that a company's helmets comply with the
standard, without having itself to test helmets. U.S. manufacturers and
importers of bicycle helmets will also have to label their products
with specified information.
The rule thus contains ``collection of information requirements''
subject to the Paperwork Reduction Act of 1995, 15 U.S.C. 3501-3520,
Pub. L. No. 104-13, 109 Stat. 163 (1995). An agency may not conduct or
sponsor, and a person is not required to respond to, a collection of
information unless it displays a currently valid OMB control number.
The control number may be displayed by publication in the Federal
Register. Accordingly, the Commission submitted the proposed collection
of information requirements to OMB for review under section 3507(d) of
the Paperwork Reduction Act of 1995.
The Commission's staff estimates that there are about 30
manufacturers and importers subject to these collection of information
requirements. There are an estimated 200 different models of bicycle
helmets currently marketed in the U.S.
Industry sources advised the Commission's staff that the time that
will be required to comply with the collection of information
requirements will be from 100 to 150 hours per model per year.
Therefore, the total amount of time required for compliance with these
requirements will be 20,000 to 30,000 hours per year. However, these
estimates are based on the amount of time that is currently expended in
complying with the similar requirements that are in the various
voluntary standards. Thus, the additional burden of the final
collection of information requirements is expected to be only a small
fraction of the total hours given above.
The Commission solicited comments on the activities and time
required to comply with these requirements and how these differ from
usual and customary current industry practices, on the accuracy of the
Commission's burden estimate, and on how that burden could be reduced.
No comments directly addressed the Commission's burden estimate.
Comments addressing the topic of reducing the number of helmets
required to be tested under the standard are discussed in section C of
this notice.
I. Executive Orders
This rule has been evaluated for federalism implications in
accordance with Executive Order No. 12,612, and the rule raises no
substantial federalism concerns.
Executive Order No. 12,988 requires agencies to state the
preemptive effect, if any, to be given to the regulation. The
preemptive effect of this rule is established by 15 U.S.C. 2075(a),
which states:
(a) Whenever a consumer product safety standard under [the CPSA]
is in effect and applies to a risk of injury associated with a
consumer product, no State or political subdivision of a State shall
have any authority either to establish or to continue in effect any
provision of a safety standard or regulation which prescribed any
requirements as to the performance, composition, contents, design,
finish, construction, packaging, or labeling of such product which
are designed to deal with the same risk of injury associated with
such consumer product, unless such requirements are identical to the
requirements of the Federal standard.
Subsection (b) of 15 U.S.C. 2075 provides that subsection (a) does
not prevent the Federal Government or the government of any State or
political subdivision of a State from establishing or continuing in
effect a safety standard applicable to a consumer product for its own
(governmental) use, and which is not identical to the consumer product
safety standard applicable to the product under the CPSA, if the
Federal, State, or political subdivision requirement provides a higher
degree of protection from such risk of injury than the consumer product
safety standard.
Subsection (c) of 15 U.S.C. 2075 authorizes a State or a political
subdivision of a State to request an exemption from the preemptive
effect of a consumer product safety standard. The Commission may grant
such a request, by rule, where the State or political subdivision
standard or regulation (1) provides a significantly higher degree of
protection from such risk of injury than the consumer product safety
standard and (2) does not unduly burden interstate commerce.
List of Subjects in 16 CFR Part 1203
Consumer protection, Bicycles, Incorporation by reference, Infants
and children, Safety.
For the reasons given above, the Commission revises Part 1203 of
Title 16 of the Code of Federal Regulations to read as follows:
PART 1203--SAFETY STANDARD FOR BICYCLE HELMETS
Subpart A--The Standard
Sec.
1203.1 Scope, general requirements, and effective date.
1203.2 Purpose and basis.
1203.3 Referenced documents.
1203.4 Definitions.
1203.5 Construction requirements--projections.
1203.6 Labeling and instructions.
1203.7 Samples for testing.
1203.8 Conditioning environments.
1203.9 Test headforms.
1203.10 Selecting the test headform.
1203.11 Marking the impact test line.
1203.12 Test requirements.
1203.13 Test schedule.
1203.14 Peripheral vision test.
1203.15 Positional stability test (roll-off resistance).
1203.16 Dynamic strength of retention system test.
1203.17 Impact attenuation test.
Subpart B--Certification
1203.30 Purpose, basis, and scope.
1203.31 Applicability date.
1203.32 Definitions.
1203.33 Certification testing.
1203.34 Product certification and labeling by manufacturers
(including importers).
Subpart C--Recordkeeping
1203.40 Effective date.
1203.41 Recordkeeping requirements.
Subpart D--Requirements for Bicycle Helmets Manufactured From March 17,
1995, Through March 10, 1999
1203.51 Purpose and basis.
1203.52 Scope and effective date.
1203.53 Interim safety standards.
Figures to Part 1203
Authority: 15 U.S.C. 2056, 2058, and 6001-6006. Subpart B is
also issued under 15
[[Page 11730]]
U.S.C. 2063. Subpart C is also issued under 15 U.S.C. 2065.
Subpart A--The Standard
Sec. 1203.1 Scope, general requirements, and effective date.
(a) Scope. The standard in this subpart describes test methods and
defines minimum performance criteria for all bicycle helmets, as
defined in Sec. 1203.4(b).
(b) General requirements.
(1) Projections. All projections on bicycle helmets must meet the
construction requirements of Sec. 1203.5.
(2) Labeling and instructions. All bicycle helmets must have the
labeling and instructions required by Sec. 1203.6.
(3) Performance tests. All bicycle helmets must be capable of
meeting the peripheral vision, positional stability, dynamic strength
of retention system, and impact-attenuation tests described in
Secs. 1203.7 through 1203.17.
(4) Units. The values stated in International System of Units
(``SI'') measurements are the standard. The inch-pound values stated in
parentheses are for information only.
(c) Effective date. The standard shall become effective March 10,
1999 and shall apply to all bicycle helmets manufactured after that
date. Bicycle helmets manufactured from March 17, 1995 through March
10, 1999, inclusive, are subject to the requirements of Subpart D,
rather than this subpart A.
Sec. 1203.2 Purpose and basis.
The purpose and basis of this standard is to reduce the likelihood
of serious injury and death to bicyclists resulting from impacts to the
head, pursuant to 15 U.S.C. 6001-6006.
Sec. 1203.3 Referenced documents.
(a) The following documents are incorporated by reference in this
standard.
(1) Draft ISO/DIS Standard 6220-1983--Headforms for Use in the
Testing of Protective Helmets.\1\
---------------------------------------------------------------------------
\1\ Although the draft ISO/DIS 6220-1983 standard was never
adopted as an international standard, it has become a consensus
national standard because all recent major voluntary standards used
in the United States for testing bicycle helmets establish their
headform dimensions by referring to the draft ISO standard.
---------------------------------------------------------------------------
(2) SAE Recommended Practice SAE J211 OCT88, Instrumentation for
Impact Tests.
(b) This incorporation by reference was approved by the Director of
the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part
51. Copies of the standards may be obtained as follows. Copies of the
draft ISO/DIS Standard 6220-1983 are available from American National
Standards Institute, 11 W. 42nd St., 13th Floor, New York, NY 10036.
Copies of the SAE Recommended Practice SAE J211 OCT88, Instrumentation
for Impact Tests, are available from Society of Automotive Engineers,
400 Commonwealth Dr., Warrendale, PA 15096. Copies may be inspected at
the Office of the Secretary, Consumer Product Safety Commission, 4330
East-West Highway, Bethesda, Maryland 20814, or at the Office of the
Federal Register, 800 N. Capitol Street NW, Room 700, Washington, DC.
Sec. 1203.4 Definitions
(a) Basic plane means an anatomical plane that includes the
auditory meatuses (the external ear openings) and the inferior orbital
rims (the bottom edges of the eye sockets). The ISO headforms are
marked with a plane corresponding to this basic plane (see Figures 1
and 2 of this part).
(b) Bicycle helmet means any headgear that either is marketed as,
or implied through marketing or promotion to be, a device intended to
provide protection from head injuries while riding a
bicycle.2
---------------------------------------------------------------------------
\1\ Helmets specifically marketed for exclusive use in a
designated activity, such as skateboarding, rollerblading, baseball,
roller hockey, etc., would be excluded from this definition because
the specific focus of their marketing makes it unlikely that such
helmets would be purchased for other than their stated use. However,
a multi-purpose helmet--one marketed or represented as providing
protection either during general use or in a variety of specific
activities other than bicycling--would fall within the definition of
bicycle helmet if a reasonable consumer could conclude, based on the
helmet's marketing or representations, that bicycling is among the
activities in which the helmet is intended to be used. In making
this determination, the Commission will consider the types of
specific activities, if any, for which the helmet is marketed, the
similarity of the appearance, design, and construction of the helmet
to other helmets marketed or recognized as bicycle helmets, and the
presence, prominence, and clarity of any warnings, on the helmet or
its packaging or promotional materials, against the use of the
helmet as a bicycle helmet. A multi-purpose helmet marketed without
specific reference to the activities in which the helmet is to be
used will be presumed to be a bicycle helmet. The presence of
warnings or disclaimers advising against the use of a multi-purpose
helmet during bicycling is a relevant, but not necessarily
controlling, factor in the determination of whether a multi-purpose
helmet is a bicycle helmet.
---------------------------------------------------------------------------
(c) Comfort or fit padding means resilient lining material used to
configure the helmet for a range of different head sizes.
(d) Coronal plane is an anatomical plane perpendicular to both the
basic and midsagittal planes and containing the midpoint of a line
connecting the right and left auditory meatuses. The ISO headforms are
marked with a transverse plane corresponding to this coronal plane (see
Figures 1 and 2 of this part).
(e) Field of vision is the angle of peripheral vision allowed by
the helmet when positioned on the reference headform.
(f) Helmet positioning index (``HPI'') is the vertical distance
from the brow of the helmet to the reference plane, when placed on a
reference headform. This vertical distance shall be specified by the
manufacturer for each size of each model of the manufacturer's helmets,
for the appropriate size of headform for each helmet, as described in
Sec. 1203.10.
(g) Midsagittal plane is an anatomical plane perpendicular to the
basic plane and containing the midpoint of the line connecting the
notches of the right and left inferior orbital ridges and the midpoint
of the line connecting the superior rims of the right and left auditory
meatuses. The ISO headforms are marked with a longitudinal plane
corresponding to the midsagittal plane (see Figures 1 and 2 of this
part).
(h) Modular elastomer programmer (``MEP'') is a cylindrical pad,
typically consisting of a polyurethane rubber, used as a consistent
impact medium for the systems check procedure. The MEP shall be 152 mm
(6 in) in diameter, and 25 mm (1 in) thick and shall have a durometer
of 60 2 Shore A. The MEP shall be affixed to the top
surface of a flat 6.35 mm (\1/4\ in) thick aluminum plate. See
Sec. 1203.17(b)(1).
(i) Preload ballast is a ``bean bag'' filled with lead shot that is
placed on the helmet to secure its position on the headform. The mass
of the preload ballast is 5 kg (11 lb).
(j) Projection is any part of the helmet, internal or external,
that extends beyond the faired surface.
(k) Reference headform is a headform used as a measuring device and
contoured in the same configuration as one of the test headforms A, E,
J, M, and O defined in draft ISO DIS 6220-1983. The reference headform
shall include surface markings corresponding to the basic, coronal,
midsagittal, and reference planes (see Figures 1 and 2 of this part).
(l) Reference plane is a plane marked on the ISO headforms at a
specified distance above and parallel to the basic plane (see Figure 3
of this part).
(m) Retention system is the complete assembly that secures the
helmet in a stable position on the wearer's head.
(n) Shield means optional equipment for helmets that is used in
place of goggles to protect the eyes.
(o) Spherical impactor is an impact fixture used in the instrument
system check of Sec. 1203.17(b)(1) to test the impact-attenuation test
equipment for
[[Page 11731]]
precision and accuracy. The spherical impactor shall be a 146 mm (5.75
in) diameter aluminum sphere mounted on the ball-arm connector of the
drop assembly. The total mass of the spherical-impactor drop assembly
shall be 5.0 0.1 kg (11.0 0.22 lb).
(p) Test headform is a solid model in the shape of a human head of
sizes A, E, J, M, and O as defined in draft ISO/DIS 6220-1983.
Headforms used for the impact-attenuation test shall be constructed of
low-resonance K-1A magnesium alloy. The test headforms shall include
surface markings corresponding to the basic, coronal, midsagittal, and
reference planes (see Figure 2 of this part).
(q) Test region is the area of the helmet, on and above a specified
impact test line, that is subject to impact testing.
Sec. 1203.5 Construction requirements--projections.
Any unfaired projection extending more than 7 mm (0.28 in.) from
the helmet's outer surface shall break away or collapse when impacted
with forces equivalent to those produced by the applicable impact-
attenuation tests in Sec. 1203.17 of this standard. There shall be no
fixture on the helmet's inner surface projecting more than 2 mm into
the helmet interior.
Sec. 1203.6 Labeling and instructions.
(a) Labeling. Each helmet shall be marked with durable labeling so
that the following information is legible and easily visible to the
user:
(1) Model designation.
(2) A warning to the user that no helmet can protect against all
possible impacts and that serious injury or death could occur.
(3) A warning on both the helmet and the packaging that for maximum
protection the helmet must be fitted and attached properly to the
wearer's head in accordance with the manufacturer's fitting
instructions.
(4) A warning to the user that the helmet may, after receiving an
impact, be damaged to the point that it is no longer adequate to
protect the head against further impacts, and that this damage may not
be visible to the user. This label shall also state that a helmet that
has sustained an impact should be returned to the manufacturer for
inspection, or be destroyed and replaced.
(5) A warning to the user that the helmet can be damaged by contact
with common substances (for example, certain solvents [ammonia],
cleaners [bleach], etc.), and that this damage may not be visible to
the user. This label shall state in generic terms some recommended
cleaning agents and procedures (for example, wipe with mild soap and
water), list the most common substances that damage the helmet, warn
against contacting the helmet with these substances, and refer users to
the instruction manual for more specific care and cleaning information.
(6) Signal word. The labels required by paragraphs (a) (2) through
(5) of this section shall include the signal word ``WARNING'' at the
beginning of each statement, unless two or more of the statements
appear together on the same label. In that case, the signal word need
only appear once, at the beginning of the warnings. The signal word
``WARNING'' shall be in all capital letters, bold print, and a type
size equal to or greater than the other text on the label.
(b) Instructions. Each helmet shall have fitting and positioning
instructions, including a graphic representation of proper positioning.
Sec. 1203.7 Samples for testing.
(a) General. Helmets shall be tested in the condition in which they
are offered for sale. To meet the standard, the helmets must be able to
pass all tests, both with and without any attachments that may be
offered by the helmet's manufacturer and with all possible combinations
of such attachments.
(b) Number of samples. To test conformance to this standard, eight
samples of each helmet size for each helmet model offered for sale are
required.
Sec. 1203.8 Conditioning environments.
Helmets shall be conditioned to one of the following environments
prior to testing in accordance with the test schedule at Sec. 1203.13.
The barometric pressure in all conditioning environments shall be 75 to
110 kPa (22.2 to 32.6 in of Hg). All test helmets shall be stabilized
within the ambient condition for at least 4 hours prior to further
conditioning and testing. Storage or shipment within this ambient range
satisfies this requirement.
(a) Ambient condition. The ambient condition of the test laboratory
shall be within 17 deg.C to 27 deg.C (63 deg.F to 81 deg.F), and 20 to
80% relative humidity. The ambient test helmet does not need further
conditioning.
(b) Low temperature. The helmet shall be kept at a temperature of
-17 deg.C to -13 deg.C (1 deg.F to 9 deg.F) for 4 to 24 hours prior to
testing.
(c) High temperature. The helmet shall be kept at a temperature of
47 deg.C to 53 deg.C (117 deg.F to 127 deg.F) for 4 to 24 hours prior
to testing.
(d) Water immersion. The helmet shall be fully immersed ``crown''
down in potable water at a temperature of 17 deg.C to 27 deg.C
(63 deg.F to 81 deg.F) to a crown depth of 305 mm 25 mm
(12 in. 1 in.) for 4 to 24 hours prior to testing.
Sec. 1203.9 Test headforms.
The headforms used for testing shall be selected from sizes A, E,
J, M, and O, as defined by DRAFT ISO/DIS 6220-1983, in accordance with
Sec. 1203.10. Headforms used for impact testing shall be rigid and be
constructed of low-resonance K-1A magnesium alloy.
Sec. 1203.10 Selecting the test headform.
A helmet shall be tested on the smallest of the headforms
appropriate for the helmet sample. A headform size is appropriate for a
helmet if all of the helmet's sizing pads are partially compressed when
the helmet is equipped with its thickest sizing pads and positioned
correctly on the reference headform.
Sec. 1203.11 Marking the impact test line.
Prior to testing, the impact test line shall be determined for each
helmet in the following manner.
(a) Position the helmet on the appropriate headform as specified by
the manufacturer's helmet positioning index (HPI), with the brow
parallel to the basic plane. Place a 5-kg (11-lb) preload ballast on
top of the helmet to set the comfort or fit padding.
(b) Draw the impact test line on the outer surface of the helmet
coinciding with the intersection of the surface of the helmet with the
impact line planes defined from the reference headform as shown in:
(1) Figure 4 of this part for helmets intended only for persons 5
years of age and older.
(2) Figure 5 of this part for helmets intended for persons age 1
and older.
(c) The center of the impact sites shall be selected at any point
on the helmet on or above the impact test line.
Sec. 1203.12 Test requirements.
(a) Peripheral vision. All bicycle helmets shall allow unobstructed
vision through a minimum of 105 deg. to the left and right sides of the
midsagittal plane when measured in accordance with Sec. 1203.14 of this
standard.
(b) Positional stability. No bicycle helmet shall come off of the
test headform when tested in accordance with Sec. 1203.15 of this
standard.
(c) Dynamic strength of retention system. All bicycle helmets shall
have a retention system that will remain intact without elongating more
than 30 mm (1.2 in.) when tested in accordance with Sec. 1203.16 of
this standard.
[[Page 11732]]
(d) Impact attenuation criteria.
(1) General. A helmet fails the impact attenuation performance test
of this standard if a failure under paragraph (d)(2) of this section
can be induced under any combination of impact site, anvil type, anvil
impact order, or conditioning environment permissible under the
standard, either with or without any attachments, or combinations of
attachments, that are provided with the helmet. Thus, the Commission
will test for a ``worst case'' combination of test parameters. What
constitutes a worst case may vary, depending on the particular helmet
involved.
(2) Peak acceleration. The peak acceleration of any impact shall
not exceed 300 g when the helmet is tested in accordance with
Sec. 1203.17 of this standard.
Sec. 1203.13 Test schedule.
(a) Helmet sample 1 of the set of eight helmets, as designated in
Table 1203.13, shall be tested for peripheral vision in accordance with
Sec. 1203.14 of this standard.
(b) Helmet samples 1 through 8, as designated in Table 1203.13,
shall be conditioned in the ambient, high temperature, low temperature,
and water immersion environments as follows: helmets 1 and 5--ambient;
helmets 2 and 7--high temperature; helmets 3 and 6--low temperature;
and helmets 4 and 8--water immersion.
(c) Testing must begin within 2 minutes after the helmet is removed
from the conditioning environment. The helmet shall be returned to the
conditioning environment within 3 minutes after it was removed, and
shall remain in the conditioning environment for a minimum of 2 minutes
before testing is resumed. If the helmet is out of the conditioning
environment beyond 3 minutes, testing shall not resume until the helmet
has been reconditioned for a period equal to at least 5 minutes for
each minute the helmet was out of the conditioning environment beyond
the first 3 minutes, or for 4 hours, (whichever reconditioning time is
shorter) before testing is resumed.
(d) Prior to being tested for impact attenuation, helmets 1-4
(conditioned in ambient, high temperature, low temperature, and water
immersion environments, respectively) shall be tested in accordance
with the dynamic retention system strength test at Sec. 1203.16.
Helmets 1-4 shall then be tested in accordance with the impact
attenuation tests on the flat and hemispherical anvils in accordance
with the procedure at Sec. 1203.17. Helmet 5 (ambient-conditioned)
shall be tested in accordance with the positional stability tests at
Sec. 1203.15 prior to impact testing. Helmets 5-8 shall then be tested
in accordance with the impact attenuation tests on the curbstone anvil
in accordance with Sec. 1203.17. Table 1203.13 summarizes the test
schedule.
Table 1203.13.--Test Schedule
----------------------------------------------------------------------------------------------------------------
Sec. Sec. 1203.17 Impact tests
Sec. Sec. 1203.16 ----------------------------------
1203.14 1203.15 Retention Number of
Peripheral Positional system Anvil Impacts
----------------------------------------vision-------stability-----strength-------------------------------------
Helmet 1, Ambient.................. X ............ X X Flat............. 2
X Hemi............. 2
Helmet 2, High Temperature......... ............ ............ X X Flat............. 2
X Hemi............. 2
Helmet 3, Low Temperature.......... ............ ............ X X Flat............. 2
X Hemi............. 2
Helmet 4, Water Immersion.......... ............ ............ X X Flat............. 2
X Hemi............. 2
Helmet 5, Ambient.................. ............ X ............ X Curb............. 1
Helmet 6, Low Temperature.......... ............ ............ ............ X Curb............. 1
Helmet 7, High Temperature......... ............ ............ ............ X Curb............. 1
Helmet 8, Water Immersion.......... ............ ............ ............ X Curb............. 1
----------------------------------------------------------------------------------------------------------------
Sec. 1203.14 Peripheral vision test.
Position the helmet on a reference headform in accordance with the
HPI and place a 5-kg (11-lb) preload ballast on top of the helmet to
set the comfort or fit padding. (Note: Peripheral vision clearance may
be determined when the helmet is positioned for marking the test
lines.) Peripheral vision is measured horizontally from each side of
the midsagittal plane around the point K (see Figure 6 of this part).
Point K is located on the front surface of the reference headform at
the intersection of the basic and midsagittal planes. The vision shall
not be obstructed within 105 degrees from point K on each side of the
midsagittal plane.
Sec. 1203.15 Positional stability test (roll-off resistance).
(a) Test equipment.
(1) Headforms. The test headforms shall comply with the dimensions
of the full chin ISO reference headforms sizes A, E, J, M, and O.
(2) Test fixture. The headform shall be secured in a test fixture
with the headform's vertical axis pointing downward and 45 degrees to
the direction of gravity (see Figure 7 of this part). The test fixture
shall permit rotation of the headform about its vertical axis and
include means to lock the headform in the face up and face down
positions.
(3) Dynamic impact apparatus. A dynamic impact apparatus shall be
used to apply a shock load to a helmet secured to the test headform.
The dynamic impact apparatus shall allow a 4-kg (8.8-lb) drop weight to
slide in a guided free fall to impact a rigid stop anvil (see Figure 7
of this part). The entire mass of the dynamic impact assembly,
including the drop weight, shall be no more than 5 kg (11 lb).
(4) Strap or cable. A hook and flexible strap or cable shall be
used to connect the dynamic impact apparatus to the helmet. The strap
or cable shall be of a material having an elongation of no more than 5
mm (0.20 in.) per 300 mm (11.8 in.) when loaded with a 22-kg (48.5 lb)
weight in a free hanging position.
(b) Test procedure.
(1) Orient the headform so that its face is down, and lock it in
that orientation.
(2) Place the helmet on the appropriate size full chin headform in
accordance with the HPI and fasten the retention system in accordance
with the manufacturer's instructions. Adjust the straps to remove any
slack.
(3) Suspend the dynamic impact system from the helmet by
positioning the flexible strap over the helmet along
[[Page 11733]]
the midsagittal plane and attaching the hook over the edge of the
helmet as shown in Figure 7 of this part.
(4) Raise the drop weight to a height of 0.6 m (2 ft) from the stop
anvil and release it, so that it impacts the stop anvil.
(5) The test shall be repeated with the headform's face pointing
upwards, so that the helmet is pulled from front to rear.
Sec. 1203.16 Dynamic strength of retention system test.
(a) Test equipment.
(1) ISO headforms without the lower chin portion shall be used.
(2) The retention system strength test equipment shall consist of a
dynamic impact apparatus that allows a 4-kg (8.8-lb) drop weight to
slide in a guided free fall to impact a rigid stop anvil (see Figure 8
of this part). Two cylindrical rollers that spin freely, with a
diameter of 12.5 0.5 mm (0.49 in. 0.02 in.)
and a center-to-center distance of 76.0 1 mm (3.0
0.04 in.), shall make up a stirrup that represents the
bone structure of the lower jaw. The entire dynamic test apparatus
hangs freely on the retention system. The entire mass of the support
assembly, including the 4-kg (8.8-lb) drop weight, shall be 11 kg
0.5 kg (24.2 lb 1.1 lb).
(b) Test procedure.
(1) Place the helmet on the appropriate size headform on the test
device according to the HPI. Fasten the strap of the retention system
under the stirrup.
(2) Mark the pre-test position of the retention system, with the
entire dynamic test apparatus hanging freely on the retention system.
(3) Raise the 4-kg (8.8-lb) drop weight to a height of 0.6 m (2 ft)
from the stop anvil and release it, so that it impacts the stop anvil.
(4) Record the maximum elongation of the retention system during
the impact. A marker system or a displacement transducer, as shown in
Figure 8 of this part, are two methods of measuring the elongation.
Sec. 1203.17 Impact attenuation test.
(a) Impact test instruments and equipment.
(1) Measurement of impact attenuation. Impact attenuation is
determined by measuring the acceleration of the test headform during
impact. Acceleration is measured with a uniaxial accelerometer that is
capable of withstanding a shock of at least 1000 g. The helmet is
secured onto the headform and dropped in a guided free fall, using a
monorail or guidewire test apparatus (see Figure 9 of this part), onto
an anvil fixed to a rigid base. The center of the anvil shall be
aligned with the center vertical axis of the accelerometer. The base
shall consist of a solid mass of at least 135 kg (298 lb), the upper
surface of which shall consist of a steel plate at least 12 mm (0.47
in.) thick and having a surface area of at least 0.10 m\2\ (1.08
ft\2\).
(2) Accelerometer. A uniaxial accelerometer shall be mounted at the
center of gravity of the test headform, with the sensitive axis aligned
within 5 degrees of vertical when the test headform is in the impact
position. The acceleration data channel and filtering shall comply with
SAE Recommended Practice J211 OCT88, Instrumentation for Impact Tests,
Requirements for Channel Class 1000.
(3) Headform and drop assembly--centers of gravity. The center of
gravity of the test headform shal
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