ID: nht67-1.30

DATE: 02/27/67

FROM: AUTHOR UNAVAILABLE; William Haddon, Jr., M.D.; NHTSA

TO: North America Seat Belt Council, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of February 16, 1967.

Motor Vehicle Safety Standard No. 209 applies to seat belt assemblies manufactured after February 28, 1967, for use in passenger cars, multipurpose passenger vehicles, trucks, and buses. Since Motor Vehicle Safety Standard No. 208, which provides that a Type 1 or Type 2 seat belt assembly that conforms to Motor Vehicle Safety Standard No. 209 shall be installed in each passenger car seat position, has an effective date of January 1, 1968, until that date seat belt assemblies installed in passenger cars need not conform to Standard No. 209 unless the seat belt assemblies have been manufactured after February 28, 1967.

Please do not hesitate to call upon us if we can be of further service to you.

ID: 23060ogm

James D. Sillery, Esq.
Mollica, Gall, Sloan and Sillery Co., L.P.A.
35 North College St.
Post Office Drawer 958
Athens, OH 45701





Dear Mr. Sillery:

This responds to your April 25, 2001, letter in which you relate an incident in which the seats of a 1999 Toyota Camry automobile collapsed in a rearward direction after the vehicle was struck from behind. You further indicate that the manufacturer of the vehicle has indicated to you that the seats in question were designed to "yield" in the event of a rear impact in order to absorb the energy that would otherwise be transmitted to the seat occupant in a rear end collision. You are concerned about the potential safety consequences of such a seat collapse for both the occupant of the seat and other occupants sitting to the rear of an occupied seat. Due to your concern, you ask if the issue of seat back strength has been "dealt with" by this agency and what the agency's position is in regard to these seats.

We would like to begin by explaining that the National Highway Traffic Safety Administration (NHTSA) is authorized to issue Federal motor vehicle safety standards that set performance requirements for new motor vehicles and items of motor vehicle equipment. Manufacturers are required to certify that their products conform to our safety standards before they can be offered for sale.

NHTSA is very concerned about seat back strength and performance. The agency's present performance standard for seats, Standard No. 207 (49 CFR 571.207) went into effect for passenger cars in 1968 and was extended to multipurpose vehicles, trucks and buses in 1972. Since that time NHTSA has embarked on a number of actions intended to study the feasibility of upgrading the standard's requirements. In 1989, the agency granted five petitions for rulemaking. Each requested that NHTSA consider certain changes to Standard No. 207. Pursuant to the granting of these petitions, NHTSA published a Request for Comments in the Federal Register (57 FR 54958) in November 1992 asking for input on agency research findings and a proposed research plan. (Responses to the request for comments, which you may find illuminating, can be accessed through the Department of Transportation's electronic docket system at http://dms.dot.gov/ under docket number 4064.) Since the publication of the Request for Comments, NHTSA has performed a study of the relationship between seat performance and injuries and conducted research aimed at gaining a greater understanding of seat performance and the means for improving seat performance ⁽¹⁾.

We note that your letter asks for the agency's position on "these kinds of seats." We assume that in referring to "these kinds of seats" that you are asking for NHTSA's view on seats that deform or "collapse" in a rearward direction in a serious rear impact and whether seats that deform or "yield" in a rear impact are desirable.

For many years, there has been considerable debate among automotive safety experts regarding the level of seat back stiffness. The issues surrounding this debate are quite complex and the agency is assessing the merits of several options related to the modification of the seat standard. We anticipate issuing a Notice of Proposed Rulemaking to upgrade this standard next spring. However, as the agency's proposal has not yet been released, we cannot provide you with more specific information at this time.

I hope this information is helpful to you. If you have any questions or need further information, please feel free to contact Otto Matheke of this office at

(202) 366-3820.

Sincerely,

John Womack
Acting Chief Counsel

ref:207
d.10/25/01





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1. ¹( http://www.nhtsa.dot.gov/cars/rules/crashworthy/Seats/index.html)
( http://www-nrd.nhtsa.dot.gov/departments/nrd-01/summaries/B0119.html)

ID: nht78-2.15

DATE: 03/15/78

FROM: AUTHOR UNAVAILABLE; J. J. Levin, Jr.; NHTSA

TO: Vetter Fairing Company

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of February 1, 1978, on motorcycle headlighting.

You have asked whether the prohibition in SAE J580a Sealed Beam Headlamp against headlamp covers applies to a motorcycle. You have also asked the reason for the prohibition.

SAE J580a Sealed Beam Headlamp is incorporated by reference in Table III of Standard No. 108 as one of the standards applicable to headlamps for use on passenger cars, and on multipurpose passenger vehicles, trucks, and buses whose overall width is less than 80 inches. One of the SAE standards incorporated by reference for motorcycle headlighting is J584 which, as an option, allows motorcycles to be equipped with headlamps "meeting the requirements of SAE J579" (i.e. passenger car sealed beam headlamps). There is no reference in J579a to J580a, and we therefore do not read the prohibition against headlamp covers as applying to motorcycles equipped with sealed or unsealed headlamps.

The reason for the prohibition is the degradation in Light output that can result from condensation under unsealed glass covers or from obscuration by grilles in front of the lens.

SINCERELY,

Vetter Fairing Company

February 1, 1978

Office of Chief Council Joseph J. Levin, Jr. National Highway Traffic Safety Admin.

Dear Sir:

After reviewing Title 49 Code of Federal Regulations 571.108, Motor Vehicle Safety Standard Number 108, Lamps, Reflective Devices and Associated Equipment, I find a need to have several points of this regulation, relevant to our business, clarified and interpreted per your office.

Table III, Required Motor Vehicle Lighting Equipment, Item - Headlamps, references the applicable SAE standard or recommende practice for passenger cars, multipurpose passenger vehicles, trucks and buses to be, in part, SAE J580a, June 1966. Contained within SAE J580a, sealed beam headlamp, under General Requirements it states "A headlamp, when in use, shall not have any styling or other feature, such as a glass cover or grille in front of the lens."

Is it correct to assume that this prohibition does not apply to a motorcycle or to a motorcycle with attached side car? Also would you please state the reason/s why passenger cars are prohibited from having any styling or other feature, such as a glass cover or grille in front of the lens when a headlamp is in use?

Table III, Required Motor Vehicle Lighting Equipment, Item - Headlamps, references the applicable SAE standard or recommended practice for motorcycles to be, in part, SAE J584, April 1964. Standard SAE J584, motorcycle and motor driven cycle headlamps makes no mention of any prohibition of having any styling or other feature, such as a glass cover or grille in front of the lens when a headlamp is in use.

Is it correct to infer that it is legal and within the scope of Motor Vehicle Safety Standard Number 108, to have styling or other feature, such as a glass cover, or plastic cover or grille in front of the lens when a headlamp is in use on a motorcycle or on a motorcycle with attached side car?

It is in the intent of Vetter Fairing Company as a manufacturer of motorcycle accessories to conceive, research, design, produce, manufacture and market motorcycle accessories which meet or exceed all Federal Motor Vehicle Safety Standards of the National Highway Traffic Safety Administration, Department of Transportation.

Your review of any and all applicable regulations relevant to our business is appreciated and your interpretation of such regulations pertaining to the above questions is requested so that we can meet our obligations, to consumers, to manufacturer motorcycle accessories which are safe and which comply with all Federal Motor Vehicle Safety Standards.

W. W. Schwartz Technical Engineer Research & Development Dept.

cc: C. VETTER C. PERETHIAN

ID: nht68-1.19

DATE: 08/12/68

FROM: AUTHOR UNAVAILABLE; Robert M. O'Mahoney; NHTSA

TO: Robert Bosch GMBH

TITLE: FMVSS INTERPRETATION

TEXT: The Bureau of Customs has forwarded to us for further reply a copy of your letter to them of May 21 asking whether lighting units for passenger cars, which do not conform to the requirements of Federal motor vehicle safety standard No. 108, may be admitted to the United States after January 1, 1969.

Amended Federal standard No. 108, effective January 1, 1969, specifies lighting requirements for various categories of motor vehicle including passenger cars manufactured on or after that date. It does not specify requirements for individual items, or lighting equipment. This means that these individual items, no matter what the date of manufacture, may be imported into the United States after January 1, 1969, because they will have been manufactured on a date when there were no standards in effect applicable to them.

I hope this answers your question.

Sincerely,

TREASURY DEPARTMENT

BUREAU OF CUSTOMS

JUN 25 1968

AIRMAIL

A. Hammerstein Robert Bosch Gmbh

Dear Mr. Hamorstein:

This will acknowledge receipt of your letter dated May 21, 1968 a copy of which was forwarded to the Secretary of Transportation, concerning the application of Federal Safety Standard 108 to lighting uniss that are now being manufactured by Robert Bosch Gmbh.

The joint regulations of the Bureau of Customs and the Department of Transportation, copy enclosed, provide in section 12.80(b)(2)(i) for the importation of a non-conforming vehicle or equipment item if they were manufactured on a date when there were no applicable safety standards in force. Therefore, these lighting units manufactured prior to January 1, 1969, and offered for importation into the United States do not have to be in conformity with Federal Safety Standard 108.

Since your inquiry concerns a specific safety standard not yet in effect, we are forwarding your letter to the Department of Transportation, Highway Safety Bureau, Washington, D.C., for their consideration and direct reply.

Sincerely yours,

John D. Roeison

Assistant Director

(Entry and Liquidation)

Division of Appraisement and Collections

Enclosure 50359

cc: Department of Transportation

ROBERT BOSCH GMBH

CC: Alan S. Boyd

Secretary of Transportation

Lester D. Johnson Commissioner of Customs Department of the Treasury Bureau of Customs

Subject: Title 19-Customs Duties (T.D. 68-16) - Part 12-Special Classes of Merchandise - Importation of Motor Vehicles and Items of Motor Vehicle Equipment - Federal Register Vol. 33, No. 6 of January 10, 1968

Gentlemen:

With the above mentioned publication, certain conditions are imposed for the importation of motor vehicle equipment into the United States.

In our opinion, one case occurring in practice is not covered by the exception granted under section (b). This is the case when replacement items are delivered for automotive vehicle manufactured before entering into force of a relevant Federal Safety Standard.

We are for instance to deliver lighting units equipped with white parking lamps for passenger cars, which are evidently not conforming to Federal Safety Standard 108.

The problem is now, whether it is possible and admissible to import such items and other ones into the United States after January 1, 1969. We add that it is well evident that such items are needed after this date, because vehicles are already equipped in such a manner and it would in our opinion to be too costly to replace two lighting units conforming to the rel;evant Federal Safety Standard, if only one replacement unit not conforming to the relevant Federal Safety standard is needed for a passenger car manufactured before January 1, 1969.

We should be very glad to have a rapid answer from you, since we have already now to care for corresponding replacement units. Leadtime is already now very scare.

Very truly yours,

A. Hammerstein

ID: nht76-1.11

DATE: 05/11/76

FROM: AUTHOR UNAVAILABLE; S. P. Wood; NHTSA

TO: Gilbert Theissen

TITLE: FMVSS INTERPRETATION

TEXT: This is in response to your letter of February 5, 1976, to Mrs. Winifred Desmond of this agency concerning braking and rollover characteristics of the Jeep vehicle. We are sorry for the delay in our answer.

The Jeep Corporation is correct in saying that 49 CFR 571.105-75, Hydraulic Brake Systems, applies only to passenger cars. It will also apply to school buses manufactured after October 25, 1976. Part 575, Consumer Information Regulations, applies as a whole to all motor vehicles (49 CFR 575.4), but the consumer information item requiring reports on brake performance is limited to passenger cars and motorcycles (49 CFR @ 571.101).

With regard to rollover resistance, the agency has issued an advance notice of proposed rulemaking to collect information on rollover resistance, but no requirement to report on rollover performance exists at this time.

ID: nht91-2.41

DATE: March 20, 1991

FROM: H. Hurley Haywood -- Vice President, Brumos Motor Cars, Inc.

TO: Chief Consul -- U.S. Department of Transportation, NHTSA

TITLE: None

ATTACHMT: Attached to letter dated 4-8-91 from Paul Jackson Rice to H. Hurley Haywood (A37; Part 591)

TEXT:

A company in England would like information regarding the sale of a very limited number of specially built cars in the U.S. All component parts, i.e.; engine, suspension, gear box would be manufactured by Porsche. The chassis would be a carbon fiber 962 racing tub with hand built body.

The car could be built completely in England or shipped to the U.S. as a kit car and assembled here.

The company would like information regarding low-volume manufacturers exemptions from certain DOT regulations, emmissions, passive restraints, bumper height, and all other pertinent information regarding manufacturing and sale of vehicles in the U.S.

Thank you for your cooperation.

ID: aiam0917

Dear Mr. Fish: Thank you for your letter of October 27, 1972, inquiring abou information on fuel tanks.; The location of fuel tanks in passenger cars is at the option of th vehicle manufacturer, since there are no Federal motor vehicle safety standards (FMVSS) concerned with tank location. The FMVSS are essentially performance oriented, and the manufacturer has the freedom for innovation and use of his own expertise in selecting the means for compliance to a specified safety performance requirement. FMVSS No. 301, which has been in effect since January 1, 1968, specifies certain fuel containment requirements as the result of a front-end impact at 30 miles per hour into a fixed barrier. Proposed amendments for FMVSS No. 301 have been issued specifying performance requirements for rear-end impacts, but the final rule has not yet been issued. The effective date for this amendment, when issued, has now been indicated as September 1, 1976. Copies of FMVSS No. 301 and the Notice of Proposed Rule Making are enclosed for your interest. A copy of Public Law 89-563 is also enclosed with a booklet briefly describing the current standards.; A number of research studies have been completed on fuel systems, an some statistical data is provided in these reports which may be of some interest. These reports are available form the National Technical Information Service, U.S. Department of Commerce, 5285 Port Royal Road, Springfield, Virginia 22151, at a price of three dollars per volume. The NTIS code number must be identified when ordering. >>>1. An Assessment of Automotive Fuel System Hazards, Dynamic Science Final Report on Contract No. FH-11-7579, December 1971, NTIS Codes PB-208240 and PB-208241 (2 volumes); 2. Impact Intrusion Characteristics of Fuel Systems, Contract No FH-11- 7309 (Cornell Aeronautical Laboratory, Inc.) April 1970, NTIS Code PB-195347; 3. Fuel Tank Protection: Fairchild-Hiller, Contract No. FH-11-6919 June 1969, NTIS Code PB-191148 (1 volume); 4. Investigation of Motor Vehicle Performance Standards for Fuel Tan Protection: Fairchild-Hiller, Contract No. FH-11- 6608, September 1967, NTIS Code PB-177690 (1 volume).<<<; The correspondence containing comments from manufacturers and othe interested parties, together with other documentation concerning the rule making action to amend FMVSS No. 301, Fuel System Integrity, is contained in the public record. Docket No. 70-20 identifies this rule making action, and this file is available for examination in the National Highway Traffic Safety Administration Office of the Chief Counsel, 400 Seventh Street, S.W., Room 5221, Washington, D.C. 20590.; We trust this information will provide some of the data you ar seeking.; Sincerely, Robert L. Carter, Associate Administrator, Motor Vehicl Programs;

ID: 1985-02.36

TYPE: INTERPRETATION-NHTSA

DATE: 05/29/85

FROM: AUTHOR UNAVAILABLE; Jeffrey R. Miller; NHTSA

TO: Ab Tunaverken

TITLE: FMVSS INTERPRETATION

TEXT:

AB Tunaverken Narjeholmevagen 18 S-633 46 Eskilstuna SWEDEN (Sverige)

Dear Sirs:

This responds to your recent letter to this office seeking information about this agency's requirements applicable to the importation of rims for use on trucks and buses. You were particularly interested in learning the requirements for you to use the DOT symbol on your rims, and asked what technical support the agency would need to make that determination.

All rims for use on trucks and buses which are imported into or sold in the United States customs territory must satisfy Federal Motor Vehicle Safety Standard No. 120, Tire Selection and Rims for Motor Vehicles Other Than Passenger Cars (49 CFR S571.120; copy enclosed). This standard specifies two requirements applicable to these rims. The first requirement, set forth in section S5.1.1, is that the rims mounted on a new vehicle must correspond with the size tire on the vehicle. That is, the rim size must be listed as suitable for use with that tire size by the tire manufacturer. This requirement is the sole responsibility of the vehicle manufacturer, since only the vehicle manufacturer knows what size tires will be mounted on the rim.

The second requirement, set forth in section S5.2, is that the rim be marked by the rim manufacturer with five specified items of information. These are:

(1) A specified designation indicating the source of the rim's published nominal dimensions;

(2) The rim's size designation and, in the case of multipiece rims, the rim type designation;

(3) The symbol DOT, which constitutes a certification by the rim manufacturer that the rim complies with the applicable requirements of the safety standards;

(4) A designation identifying the rim manufacturer by name, trademark, or symbol; and

(5) The month and year in which the rim was manufactured.

You stated that you were interested in knowing the requirements for you to mark your rims with the symbol "DOT." The United States does not use a certification process similar to the European countries, in which the manufacturer delivers the rims to be certified to a governmental entity, and that entity tests the rims to determine if they can be certified as complying with the applicable standards. Instead, in the United States, the individual rim manufacturer must certify that its rims comply with all applicable standards. In the case of rims for use on trucks and buses, Standard No. 120 contains all the applicable requirements. The certification need not be based on actual tests; the only requirement is that the manufacturer exercise due care when making the certification. Obviously, in the case of rims for use on trucks and buses, no testing is necessary since the standard only sets marking requirements for those rims. Once the manufacturer determines that these rims satisfy those requirements, it marks the symbol "DOT" on the rims.

If either your company or this agency determines that your rims do not comply with the requirements of Standard No. 120 or determine that the rims contain a defect related to motor vehicle safety, your company would be required to remedy the defect or noncompliance. Section 154(a)(2)(B) of the National Traffic and Motor Vehicle Safety Act (15 U.S.C. 1414(a)(2)(B) specifies that, if the rims fail to comply with Standard No. 120 or contain a safety-related defect, the manufacturer must notify purchasers of the safety-related defect or noncompliance and must either:

(1) repair the rim so that the defect or noncompliance is removed; or

(2) replace the rim with an identical or reasonably equivalent rim which does not have a defect or noncompliance.

Whichever of these options is chosen, the rim manufacturer must bear the full expense and cannot charge the rim owner for the remedy if the rim was first purchased less than 8 years before the notification campaign.

Additionally, I am enclosing copies of two procedural rules which apply to all parties subject to the regulations of this agency. The first is 49 CFR Part 566, Manufacturer Identification. This requires your company to submit your name, address, and a brief description of the items of equipment you manufacture (aluminum wheels for cars, trucks, and buses) to the agency within 30 days of the date your wheels are shipped into the United States.

The other regulation is 49 CFR Part 551, Procedural Rules. This regulation requires all manufacturers headquartered outside of the United States to designate a permanent resident of the United States as the manufacturer's agent for service of process in this country. The individual designated as the agent may be either a person or a business entity. Part 551 specifies that the designation of agent must contain the following six items of information:

1. A certification that the designation is valid in form and binding on your company under the laws, corporate by-laws, or other requirements governing the making of the designation at the time and place where it is made;

2. The full legal name, principal place of business, and mailing address of your company;

3. Marks, trade names, or other designation of origin of any of your wheels and rims which do not bear the name of your company;

4. A statement that the designation shall remain in effect until withdrawn or replaced by your company;

5. A declaration of acceptance duly signed by the agent appointed by your company, and that agent may be an individual, firm, or U.S. corporation; and

6. The full legal name and address of the designated agent.

This designation should be received by this agency before you ship your wheels and rims into the United States.

If you need further information, or a clarification of any of the information contained herein, please do not hesitate to contact me.

Sincerely,

Jeffrey R. Miller Chief Counsel

Enclosures

Chief council National Highway traffic Safety Administration 400 7th street S.W. Washington D.C. 20590 USA

Attn: Steven Kratcke.

Dear Sir!

Tunaverken is a manufacturer of aluminium wheels for cars, trucks and buses.

Since half a year there have been requests from bus and truck manufacturers that they should be able to use our wheels on buses and trucks used in the USA.

We would like to know the requirements in order to use the "DOT" symbol. Are all requirements in the S 571.120 Standard No. 120 Tire selection and Rims for Motor vehicles other than Passenger Cars. What technical support do You need, test reports a.s.o. If the vehicle manufacturer sells the wheels with its own name on the wheel and not ours, should they apply for the "DOT" symbol?

We would appreciate very much if we could get an answer soon.

Yours Sincerely

AB TUNAVERKEN MK:bam

ID: nht90-3.98

TYPE: Interpretation-NHTSA

DATE: July 5, 1990

FROM: Roger C. Fairchild -- Esq., Shutler and Low

TO: Paul Jackson Rice -- Chief Counsel, NHTSA

TITLE: None

ATTACHMT: Attached to letter dated 9-26-90 from P.J. Rice to R.C. Fairchild (A36; Std. 109; Std. 110; Std. 119; Std. 120)

TEXT:

Our firm advises a number of motor vehicle industry clients regarding their obligations under various Federal statutes and regulations. On behalf of a client, we request your opinion regarding the proper interpretation of Federal Motor Vehicle Safety Standards 110 and 120 (49 C.F.R. 571.110 and 571.120), as they relate to certain recommendations for tire selection and pressure/load determinations contained in publications of the Tire and Rim Association ("TRA").

Background

The TRA Year Book is one of the tire industry standardization publications that are listed in section 4.4.1(b) of FMVSS 109 and in section 5.1(b) of FMVSS 119. Under section 4.2.1(c) of FMVSS 109 and section 6.6 of FMVSS 119, tires must have maximum load ratings (molded on the sidewall in accordance with section 4.3(c) of FMVSS 109 and section 6.5(d) of FMVSS 119) that are not less than the lowest of any specified values printed in the listed publications, for tires of that size designation. Under section 4.2.1 of FMVSS 110, the vehicle maximum load on a tire may not be greater than the maximum load rating on the tire sidewall. In addition, section 4.3.1(c) of FMVSS 110 provides that, if a tire pressure other than the maximum pressure is specified on a passenger car tire placard, the vehicle loading condition for that pressure must be specified, and that pressure must be one that will support the vehicle load on the applicable tire, as specified in the listed publications or in a separate submittal by the tire manufacturer. Moreover, it is our understanding that NHTSA has interpreted FMVSS 120 to require that, for vehicles other than passenger cars, the vehicle load on each tire (at the recommended inflation pressure) must not exceed the tire's load rating at that pressure, as specified in the listed publications.

Thus, NHTSA generally requires that the tire selection process and tire information labels must reflect pressure/load relationships that are determined by reference to publications such as the TRA Year Book. However, NHTSA standards do not specify the exact part of each of these publications that is to be used in determining compliance with NHTSA standards. In fact, the publications include some "advisory" requirements that do not appear to be used in determining compliance with the FMVSS.

Examples of TRA criteria that are not clearly referred to in NHTSA standards are those criteria relating to vehicle speed capability.

Although FMVSS 109 and 119 include tire high speed tests, we understand that, in general, no separate provision is made in the FMVSS to account for vehicle high speed capability.

Questions

We request that you inform us as to whether the following three TRA criteria are used in determining compliance with FMVSS:

1. Vehicle Load Adjustment for Speed (Passenger Cars)

The 1990 edition of the TRA Year Book provides that "for applications above 210 km/h (130 mph), both vehicle normal load and vehicle maximum load shall be multiplied by a factor" that is based on the vehicle's maximum speed capability (see Enclosure 1). The Year Book goes on to state that "the resultant vehicle normal load must not exceed 88 percent of the tire maximum load and the resultant vehicle maximum load must not exceed the tire maximum load. In addition, the resultant vehicle maximum load as determined above must not exceed the tire load corresponding to the inflation pressure specified by the vehicle manufacturer."

It is our understanding that the adjustment factor described above is not used in determining compliance with FMVSS 110 or 120. As with the TRA provisions, section 4.2 of FMVSS 110 requires that the vehicle normal load on a tire must not exceed 88 percent of the tire's maximum load rating and the vehicle maximum load on a tire must not exceed the maximum load rating (as marked on the tire sidewall). However, unlike the TRA provisions, the terms "vehicle normal load" and "vehicle maximum load" are defined in section 3 of FMVSS 110 without reference to the speed capability of the vehicle. No explicit reference to the above described adjustment factor appears anywhere in the Federal standards. Therefore, we conclude that the vehicle speed adjustment factor is not applicable under the Federal standards.

2. Vehicle Speed Adjustment for Inflation Pressure (Passenger Cars)

The TRA Year Book also requires that the "speed category of the tire must match or exceed the theoretical maximum speed of the vehicle." The theoretical maximum speed of the vehicle is defined by TRA as the actual maximum speed, as adjusted for tire inflation pressure using another factor specified by TRA. (See Enclosure 2.) TRA also recommends minimum inflation pressures for vehicles of high maximum speed capability. We are aware of no reference anywhere in NHTSA regulations to tire speed categories. Therefore, it is our understanding that the TRA provisions set forth in Enclosure 2 are not used in determining compliance with Federal safety standards.

3. Load Limits at Various Speeds for Diagonal and Radial Ply Truck Tires

TRA also provides for adjustments in recommended tire inflation pressure and "service load" for tires used on trucks and buses, depending on the maximum speed capability of the vehicle (see Enclosure 3).

FMVSS 120 does not explicitly define the required tire pressure/load relationships for trucks and buses. However, section 5.1.2 of that standard provides that the sum of the maximum load ratings of the tires

fitted to an axle must not be less than the applicable GAWR. The maximum load ratings of truck tires are determined under section 6.6 of FMVSS 119 without reference to the vehicle application. The only explicit reference in FMVSS 120 to vehicle maximum speed capability is an exclusion from the requirements of section 5.1.2 for vehicles whose maximum speed attainable in 2 miles is 50 mph or less. Thus, we do not see a basis for using the TRA standard set forth in Enclosure 3 to determine compliance with Federal standards.

Conclusion

In our opinion, the TRA Standards described above should not be used in determining compliance with Federal safety standards. In general, using such private standards would have the effect of delegating to several distinct organizations the power to amend Federal standards in ways that are potentially inconsistent. Moreover, TRA standards are typically made effective on publication, so no advance lead-time would be provided to vehicle manufacturers with respect to new TRA standards. (If NHTSA determines that the above mentioned "advisory" requirements of the TRA standards must be used in determining compliance with the FMVSS, please inform us how NHTSA would deal with this lead-time concern, consistent with section 103(e) of the Safety Act.)

If you have any questions regarding this letter, please contact me at 818-1320 (local number).

Enclosures

Selection of Tires for Passenger Cars and Station Wagons (Source: The Tire and Rim Association 1990 Year Book) (text omitted.)

Vehicle Speed Adjustment (for inflation pressure) (text omitted).

Load Limits at Various Speeds for Diagonal and Radial Ply Truck Tires Used on Improved Surfaces (text omitted).

ID: nht75-6.37

DATE: 09/05/75

FROM: BARBER B. CONABLE -- HOUSE OF REPRESENTATIVES

TO: HONORABLE WILLIAM T. COLEMAN -- SECRETARY U. S. DEPARTMENT OF TRANSPORTATION

TITLE: NONE

ATTACHMT: ATTACHED TO LETTER DATED OCTOBER 10, 1975 FROM WILLIAM T. COLEMAN, SECRETARY OF TRANSPORTATION, TO HON. BARBER B. CONABLE, HOUSE OF REPRESENTATIVES

TEXT: This letter is written in the interest of Mr. F. J. Guppenberger of Batavia, New York, to express his concern about the traffic safety hazard posed by automobiles which have been modified for racing or other purposes.

I recently received a letter about this from Mr. Guppenberger, describing the increased dangers of a collision with a car having a raised rear bumper such as is sometimes done with racing cars. Mr. Guppenberger feels that either the modifying of cars in this way or the driving of them on highways should be made illegal.

A copy of Mr. Guppenberger's letter to me on this is enclosed for your information and consideration. I will greatly appreciate a careful evaluation of the issues raised by this enclosure, including whether there are existing federal authorities in this area.