Xportation Safety Concepts Inc. (XSCI)
4143 Sinton Road
Colorado Springs, CO 80907
Dear Mr. Long:
This responds to your letter asking about S5.1.4 of Federal Motor Vehicle Safety Standard No. 213, AChild Restraint Systems.@ That provision of the standard sets limits on the back support angle provided by a rear-facing child seat.
According to your letter, your company, XSCI, is developing a rear-facing infant seat that can be used in the front seat of vehicles equipped with passenger side air bags. You state, AWe have consistently demonstrated [Head Injury Criterion] HIC values of less than 400 in standard sled tests (30+ mph). We believe we can lower these HIC values even more if we change the angle of the cradle back support that we currently are using.@ You ask whether your understanding is correct that Athe cradle [depicted in a sketch you enclosed] can be at any angle from 0 (upright) to 70 degrees (almost horizontal) and still be within FMVSS 213 guidelines.@ Our answer is yes, your understanding of S5.1.4 is correct.
S5.1.4, Back Support Angle, states:
When a rear-facing child restraint system is tested in accordance with S6.1 [Standard 213's dynamic test], the angle between the system=s back support surface for the child and the vertical shall not exceed 70 degrees.
This means that the child restraint system=s back support surface and the vertical must not exceed 70 degrees at any time during the dynamic test of Standard 213. Your sketch indicates that you correctly understand S5.1.4's reference to the angle of A70 degrees@ formed by the back support surface and the vertical.
While your understanding of S5.1.4 is correct, a few aspects of your letter should be clarified. The first aspect was discussed with you in a March 18, 1996 telephone conversation with Deirdre Fujita of my staff. As discussed in that call, S5.1.1(b) of Standard 213 requires that a child restraint that is adjustable to different positions must remain in the same adjustment position during the dynamic test that it was in immediately before the test. (There is an exception to the requirement (S5.1.1(b)(2)), but it would not apply to a restraint such as yours.) While it appears from your sketch that the infant seat may fail to remain in the same adjustment position in the test, you informed Ms. Fujita that the seat back angle is Afixed@ on your system, and thus would not change adjustment position as depicted.
Second, when you asked about S5.1.4, you referred to the specifications of FMVSS 213 as Aguidelines.@ We emphasize that the provisions set forth in S5 of the standard are not guidelines, but are requirements that apply to all new child restraint systems. Each manufacturer of a child restraint system must certify the compliance of its product to Standard 213's requirements.
For your information, Standard 213 was amended in July 1995 to incorporate additional test dummies for use in compliance tests, along with other changes to the standard as well. Under the amendment, child restraints recommended for children with a mass of up to 10 kilograms (approximately 22 pounds) may be tested by NHTSA using test dummies representing both a newborn and a nine-month-old child. I have enclosed a copy of this July 6, 1995 rule (60 FR 35126) for your convenience.
I have also enclosed an information sheet for manufacturers of motor vehicles and motor vehicle equipment. The information sheet describes manufacturers' responsibilities under Federal law (Title 49, United States Code, Chapter 301) for manufacturing vehicles and items of equipment, such as the responsibility to ensure these products do not have any safety-related defects. Under Federal law, each manufacturer must self-certify that its product complies with all applicable safety standards. The NHTSA does not approve or endorse any products.
I hope this information is helpful. If you have any other questions, please do not hesitate to contact Ms. Fujita at (202) 366-2992.
Samuel J. Dubbin Chief Counsel