Interpretation ID: aiam1602
Director
Quality Assurance
B. F. Goodrich Tire Company
500 South Main Street
Akron
OH 44318;
Dear Mr. Bader: This is to respond to the draft defect notification letter submitted b B. F. Goodrich at a meeting with NHTSA personnel on September 4, 1974. While we provided you with some preliminary comments at that time, our position regarding your notification is as stated in this letter.; We believe your letter fails to comply with 49 CFR, Part 577, 'Defec Notification' in several respects. Some of our comments are also directed at what we view as a lack of clarity in your letter arising, it seems to us, from some disorganization in the text.; The first sentence in your second paragraph does not follo satisfactorily the requirements of S 577.4(b)(1). This requirement should be met by simply stating, 'The B. F. Goodrich Tire Company has determined that a defect which relates to motor vehicle safety exists in its Space Saver Spare tire.'; Section 577.4(c) requires the notification to describe the defect b including specified information. We believe your letter confuses the items of information and presents them in an order which clouds an understanding of the safety problem. As we understand your presentation of the facts, the item of motor vehicle equipment affected (S 577.4(c)(1)) is the tire, the malfunction that may occur (S 577.4(c)(2)) is an explosion of the tire, and the operating or other conditions that may cause the malfunction to occur (S 577.4(c)(3)) are damaged beads, excessive air pressure, and beads not seated properly on the rim. With respect to this latter requirement, we find the reference to the 'combination' of factors in your second paragraph, and your fourth paragraph, in which you state that 'some or all' of the causal conditions listed can produce the defect, to be inconsistent and too imprecise to conform to the requirement. In addition to describing factors which can singly cause an explosion, if certain combinations of factors must exist in order for the defect to occur these combinations should not be stated generally as you have done, but should be specifically described. Moreover, we indicated to you at the September 4 meeting that we disagree that broken beads and excessive pressure must exist in combination in order for an explosion to occur.; Most importantly, we cannot agree upon your characterization of th bolting of the tire to the wheel before inflation as a precaution the owner can take to reduce the chance that the malfunction will occur under S 577.4(c)(4). Both literally and by implication your second and fourth paragraphs read that if the tire is bolted to the vehicle before inflation, an explosion will not occur. The malfunction, however, is an explosion of the tire, not only those explosions which cause injury. While we agree that bolting the tire to the vehicle before inflation can potentially reduce the chance of injury, it should be characterized only in this fashion. Therefore, both on page 1 of your letter and in the instructions which you begin on page 3 for persons who have need of the tire before its inspection by Goodrich, you must make it absolutely clear that bolting the tire to the vehicle has no effect whatever on whether the tire will explode, but that bolting will serve only to reduce the chance of injury if an explosion occurs.; We have the following points with respect to the remaining provision of your letter. On page 2, in the first complete paragraph, beginning 'In the majority of usage situation...etc,' we find the use of the word 'majority' confusing. The implication to us is that in a minority of situations the danger is not reduced at all. This should be clarified.; The third complete paragraph on page 2 is also confusing. There is n apparent connection between its first and second sentences. If you are attempting to say that despite what earlier labels may say that the instructions provided in this letter should be followed, then this can be stated more clearly.; The use of the word 'solely' in the fourth paragraph on page 2 is disclaimer, prohibited by section 577.6, and should be stricken.; On page 3, we believe the requirements of section 577.4(e)(1) call fo more detail than you have provided in the third paragraph on page 3. We suggest you include a description of the inspection and test cycle. As we indicated to you on September 4, the second and third paragraphs could be combined for clarity. Finally, the second sentence in your second paragraph on page 3 should be reworded to indicate more clearly that the date you have inserted is the date by which repair facilities will have necessary parts and instructions. In its present wording the meaning of the sentence is unclear.; Apart from these deficiencies, we believe your letter conforms to 4 CFR Part 577. At the same time, we believe your letter unnecessarily obscures the safety problem, and hope that, apart from literal compliance with Part 577, this is eliminated in the letter sent to purchasers. You should note that our determination of the conformity of the letter to Part 577 does not in any way indicate our agreement with Goodrich's analysis of the safety defect. We will continue to look into this matter, as appropriate, in order to determine whether Goodrich's analysis of the defect, and its consequent remedy, are fair and accurate statements of the safety problem. You should be aware that if subsequent events do show that attributing the safety defect to a mounting problem does not adequately describe the defect, further notification may be required.; Yours truly, Richard B. Dyson, Acting Chief Counsel