Interpretation ID: nht93-9.3

DATE: December 4, 1993

FROM: David Fabrycky

TO: Chief Counsel -- US DOT, NHTSA

TITLE: None

ATTACHMT: Attached To Letter Dated 5/12/94 From John Womack To David Fabrycky (A42; Std. 213; VSA 108(a)(2)(A)

TEXT: Dear Sir,

I and my associates are currently involved in the development of a child safety device that is intended to prevent the inadvertent and curiosty based opening of the safety buckle by a one to six year old. Although there have been many studies done on the value of such a device the Code of Federal Regulations contains many relevant statements regarding the testing and operation of child restraint systems.

I am writing you for the purpose of gaining your insight and opinion as to the relationship between the type of device we have developed and the standards articulated in the Code of Federal Regulations.

Our device is and after-market item purchased by the parent or gaurdian. The device covers the safety buckle and prevents the child from gaining access to the pushbutton. The adult or gaurdian is presumed to possess sufficient mannual dexterity and cognitive skills to easily remove the cover and release the safety belt. The device is also transparent so that the objective is visible.

Regarding the following sections, what is your opinion of the installation of such a device on a child's seat belt buckle in conjuction with other approved devices?

Please find several references to the Code of Federal Regulations followed by specific issues/questions in boldface.

CFR 571.214

S5.4.3.5 Buckle Release. Any buckle in a child restraint system belt assembly designed to restrain a child using the system shall: (a) When tested in accordance with S6.2.1 prior to the dynamic test of S6.1, not release when a force of less than 9 pounds is applied and shall release when a force of not more than 14 pounds is applied:

The device requires that a latch be accuated and the cover pivoted away from the buckle so that the pushbutton can be depressed. If none of the forces required to accomplish these tasks exceed the limits specified, would the device be acceptable.

The device requires the manual dexterity to exert the forces in many directions simulateously. Does this comply with the foregoing requirement?

(b) After the dynamic test S6.1, when tested in accordance with S6.2.3, release when a force of not more than 16 pounds is applied;

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The device does not bear the restraining force of any test and is designed to operate after any stress as when first installed.

(c) Meet the requirements of S4.3(d)(2) of FMVSS No. 209 (CFR 571.209), except that the minimum surface area for child restraint buckles designed for pushbutton application shall be 0.6 square inch;

The device covers the pushbutton during use. The parent or gaurdian is required to remove the device in order to access the pushbutton.

S6 Test Conditions and procedures.

This section describes in detail the procedures required for child restraint system. How would the addition of the device relate to the objectives of the tests?

S6.2 Buckle Release Test procedure.

This section describes in detail the procedures required for buckle of child restraint systems. How would the addition of the device relate to the objectives of the tests?

What other Regulations seem relevant to the development of our device and do you have other observations or opinions that relate to public policy that I have not mentioned?

Thank you in advance for your prompt response.

Sincerly