United States Department of TransportationInterpretation ID: 10949
7028 Laurel Oak Way
Fair Oaks, CA 95628
Dear Mr. Zawlocki:
This responds to your request for an interpretation of Standard No. 218, Motorcycle Helmets. Your questions are addressed below.
You first ask whether the Penetration Test (S7.2) tests the outer shell of the helmet, the Impact Attenuation Test (S7.1) tests inner protection materials, and the Retention System Test (S7.3) tests straps that hold the helmet on the head. Each of these tests measures the performance of a motorcycle helmet as a total system, i.e., the tests are conducted on a motorcycle helmet as a whole, rather than on helmet components. Therefore, the tests are not limited to measuring the performance of the components you cite. By way of example, while the shell of the helmet may play a critical role in a helmet's resistance to penetration, the composition and thickness of the liner may also be important. Similarly, while certain components are more important than others in meeting certain criteria, overall design and construction of the helmet will determine whether it meets the impact attenuation and retention requirements.
You next ask whether Standard No. 218 specifies the types or amounts of material to be used in manufacturing helmets. Standard No. 218 specifies performance requirements for motorcycle helmets. A manufacturer may use any types or amounts of materials that enable the manufacturer to fully comply with the standard.
While Standard No. 218 does not specify that certain materials must be used in manufacturing a helmet, the National Highway Traffic Safety Administration's (NHTSA) experience in over 20 years of helmet testing indicates that helmets meeting Standard No. 218 have common characteristics. The first of these is a dense foam liner that is approximately one inch thick. Helmets with thinner liners or liners composed of a soft compressible foam are not likely to meet the impact attenuation or penetration requirements of the Standard. The weight of the helmet, while not governed by any section of Standard No. 218, is also a good indicator of how it will perform in testing. Although it may be
technically possible to build a lightweight helmet that satisfies the performance requirements of Standard No. 218, NHTSA is not aware of any motorcycle helmet weighing less than three pounds that has done so.
Finally, you ask whether Standard No. 218 precludes decorating a helmet with any material such as leather or cloth, or with items such as wigs, flowers, decals or hats.
The various helmet decorations you describe could affect a motorcycle helmet's compliance with a variety of Standard No. 218's performance requirements. One example is S5.5, Projections. The inside of the shell must be free of protruding rivets or other projections. The presence of any projections within the helmet indicates that it is not a complying helmet. Projecting snaps or other objects are permitted on the outside of the helmet only if they are required for essential accessories such as visors or face shields. Any projection on the outside of a helmet must not protrude more than five millimeters.
I note that under 49 U.S.C. '30112(a), "a person may not manufacture for sale, sell, offer for sale, introduce or deliver for introduction in interstate commerce, or import into the United States" a new motorcycle helmet that does not comply with Standard No. 218. Also, dealers and repair businesses may not modify new or used motorcycle helmets in a manner that results in the helmet no longer complying with the standard. Any of these parties must therefore ensure that any contemplated decorations would not affect a helmet's compliance with Standard No. 218.
Federal law does not address modifications made by a motorcycle helmet owner to his or her own helmet. However, it is NHTSA's policy to discourage motorcycle helmet users from modifying their helmets. This is because even relatively simple modifications can reduce the safety protection provided by the helmet. S5.6.1(f)(3) of Standard No. 218 requires the following instruction to be placed on helmets: "Make no modifications..." I also note that State laws may address modifications made by motorcycle helmet owners to their own helmets.
I hope this information is helpful. If you have further questions, please contact Dorothy Nakama of my staff at (202) 366-2992.
Sincerely,
John Womack Acting Chief Counsel ref:218 d:8/29/95