Interpretation ID: aiam4203
Chief Co-ordinator of Technical Administration Dept.
Daihatsu Motor Co.
Ltd.
1. Daihatsu-Cho
Ikeda City
Osaka Prefecture
Japan;
Dear Mr. Tsujishita: This responds to your letter requesting an interpretation of several o our standards. First, I would like to apologize for the delay in this response to your letter. I have set forth the responses in the order you asked the questions in your letter.; 1. Standard No. 105, *Hydraulic Brake Systems*. Paragraph S5.2.1 of this standard provides that the parking brak system on a passenger car and some school buses shall be capable of holding the vehicle stationary *(to the limit of traction on the braked wheels) for 5 minutes in both a forward and reverse direction on a 30 percent grade. You stated that your understanding of this provision was as follows. During the tests to determine compliance with this provision, the axles of the subject vehicle must be locked by the parking brake. Your understanding is that the vehicle is permitted to slide down the 30 percent grade, and would be considered as complying with this provision of Standard No. 105 no matter how it slides as long as the vehicle's axles do not turn. This understanding is correct.; The parenthetical note in section S5.2.1 was included in the standar to address the situation where a particular 30 percent grade might have a low traction coefficient. In this situation, a vehicle might slide down the grade even though its parking brake system had held the vehicle axles locked for the required amount of time. NHTSA did not intend vehicle sliding because of a loss of traction by the tires to be considered a failure of the parking brake system. To make this item clear, section S5.2.1 specifies that the parking brake system must hold the vehicle stationary only 'to the limit of traction on the braked wheels.' This language allows the standard not to specify the traction coefficient for the 30 percent grade. Since no particular traction coefficient is specified, compliance testing may be conducted on *any* 30 percent grade that satisfies the requirement of S6.9. That section requires that the parking brake test surface be clean, dry, smooth Portland cement concrete.; 2. Standard No. 110, *Tire Selection and Rims.* Paragraph S4.3 of this standard specifies that a placard containin certain safety performance indication shall be permanently affixed to 'the glove compartment door or an equally accessible location.' You asked if the door latch post, the inner surface of the glove compartment box, and the inward-facing surface of the driver's side door would be considered 'equally accessible locations.' Each of these locations could be equally accessible locations.; In several past interpretations, we have explained that locations fo the placard would be considered equally accessible if two conditions were met. These were:; >>>1. The alternative location must result in the placard bein positioned so that the vehicle operator can readily refer to it, and; 2. The alternative location must keep the placard relatively free fro exposure to substances that could destroy the placard or render it illegible.<<<; If you position the placard on any of your three alternative location so that the vehicle operator can readily refer to it and where the placard would be protected from substances that could destroy it, we would consider each of those alternative locations as 'equally accessible locations' for the purposes of Standard No. 110.; 3. Standard No. 302, *Flammability of Interior Materials*. Paragraph S4.1 of Standard No. 302 sets forth a listing of th components of vehicle occupant compartments that must be certified as complying with the flammability resistance requirements of paragraph S4.3. You listed nine components not specifically listed in paragraph S4.1 and asked whether those components were required to be certified as meeting the flammability resistance requirements. The answer to your question depend on whether the components are designed to absorb energy on contact by occupants in the event of a crash.; paragraph S4.1. represents a complete listing of all components in ne vehicles that must comply with the flammability resistance requirements. Any component not identified in paragraph S4.1 is not subject to the flammability resistance requirements. The only item on that listing that might be applicable to the nine components about which you asked is 'any other interior materials, including padding and crash-deployed elements, that are designed to absorb energy on contact by occupants in the event of a crash.' Thus, you must determine which of the nine components you asked about are so designed. We would assume that knee bolsters are designed to absorb energy on contact by occupants in the event of a crash. These and any other of the nine components so designed must be certified as complying with the flammability requirements of Standard No. 302. Any of the nine components not designed to absorb energy are to required to comply with the flammability requirements.; 4. Part 575.101, *Consumer Information Regulations, Vehicle Stoppin Distance.*; You noted that S575.101 requires vehicle manufacturers to disseminat information about the minimum stopping distance for groups of passenger cars. Section 575.101(c) requires that each passenger car in the group to which the stopping distance information applies shall be capable of performing at least as well as the information indicates, *under the test conditions and procedures specified in S6 an S7 of Standard No. 105* (emphases added). You noted that those sections of Standard No. 105 specify both pre-burnish and post-burnish tests, and that the braking performance varies considerable for the two tests. You asked whether the consumer information on stopping distance must reflect the pre-burnish stopping distance. It need not reflect pre-burnish stopping distance.; As you noted, S575.101(c) specifies that the stopping distanc information should be measured under the test conditions and procedures specified in sections S6 and S7 of Standard No. 105. This specification was added in an amendment published on January 6, 1976 (41 FR 1066). Before that amendment, S575.101 had specified separate test conditions and procedures for the stopping distance information. Those conditions specified that the vehicle's brakes were to be burnished and then the stopping distance was to be measured. In place of those conditions, S575.101(c) now specifies that the stopping distance information should express the *minimum* stopping distances that can be met or exceeded by each vehicle in the group to which the information applies, using the test conditions and procedures of Standard No. 105. Since stopping distances decrease after burnish, the post- burnish results represent the *minimum* stopping distances that can be met or exceeded by the vehicles. Therefore, the pre-burnish stopping distances need not be reflected in the stopping distance information manufacturers make available to consumers.; Sincerely, Erika Z. Jones, Chief Counsel