Interpretation ID: aiam0497
Automotive Safety Director
Ford Motor Company
The American Road
Dearborn
MI
49121;
Dear Mr. Eckhold: This is in reply to your letter of November 2, 1971, petitioning t amend Motor Vehicle Safety Standard No. 302, 'Flammability of Interior Materials,' and offering comments concerning the notice of proposed rulemaking (Docket No. 3-3, Notice 4), published May 26, 1971 (36 F.R. 9565). You petitioned for the substitution of a 12-inch-per-minute burn rate for the 4-inch-per-minute horizontal burn rate presently specified. For the reasons stated below, your petition is hereby denied.; You base your petition on your belief that the expenditure fo materials that will comply with the 4-inch-per-minute burn rate cannot be justified in terms of the safety benefit achievable. In support of this you state that your analysis shows that the incidence of non-fuel fed fires is extremely low and the probability of injury is extremely remote. You further state that the cost necessary to comply with the standard's requirements as presently issued would involve an increase in vehicle cost from $4 to $10 per vehicle, while you presently have materials which you believe can meet a 12-inch-per-minute burn rate.; The Administration does not agree that there is insufficient data o which to justify the necessary expenditure to obtain a 4-inch-per-minute burn rate. There is ample evidence in the docket that the incidence and severity of non-fuel fires present an unreasonable risk to the public. The Administration has determined that in order for occupants to have sufficient time to escape from a vehicle fire, the material within the vehicle must have a horizontal burn rate that does not exceed 4 inches per minute. Ford has submitted no evidence to show that the 4-inch-per-minute burn rate is excessive or unreasonable from a safety standpoint. In addition, the high toxicity of some vehicle interior materials requires that they burn at a rate that is low enough that vehicle occupants will not be overcome by harmful gases before they can escape from the vehicle. We believe, based upon material found in the docket, that a burn rate of not more than 4 inches per minute is necessary to respond adequately to this need.; You argue further that your suppliers maintain that it would b difficult to meet the 4-inch-per-minute burn rate because of inherent variations in materials, and submit data showing that 'two vinyl coated seat fabrics of the same grain and dark colors' exhibited burn rates of .40 inches per minute and 6.25 inches per minute respectively. The NHTSA understands that the burn rate of some materials may vary. This fact will be taken into account, along with the frequency and extent of any test failures, in assessing whether a manufacturer has exercised due care. It would not be appropriate, however, to respond to the problem of variability by relaxing the overall burn rate. Such an action would probably result simply in manufacturers choosing cheaper and less safe materials.; You also argue that based upon your preliminary findings, aging o materials treated with fire retardants tends to nullify the retardant treatment and destroys the appearance of the material. Other data you submit shows a situation in which the flame retardants did not deteriorate, but the treatment caused deterioration of the material. The evidence available to the NHTSA does not, however, indicate that it is necessary to use flame-retardant treatments that display these undesirable characteristics in order to comply with the standard.; Finally, your petition contains no evidence that the 12-inch-per-minut burn rate that you recommend will allow sufficient escape time in the event of a vehicle fire. Based on the Administration's findings, such a rate would not provide the escape time necessary.; With reference to your comments concerning the proposed amendment t the standard of May 26, 1971, these will be considered as far as is practicable in that rulemaking action.; Sincerely, Robert L. Carter, Acting Associate Administrator, Moto Vehicle Programs;