Skip to main content

NHTSA Interpretation File Search

Overview

NHTSA's Chief Counsel interprets the statutes that the agency administers and the standards and regulations that it issues. Members of the public may submit requests for interpretation, and the Chief Counsel will respond with a letter of interpretation. These interpretation letters look at the particular facts presented in the question and explain the agency’s opinion on how the law applies given those facts. These letters of interpretation are guidance documents. They do not have the force and effect of law and are not meant to bind the public in any way. They are intended only to provide information to the public regarding existing requirements under the law or agency policies. 

Understanding NHTSA’s Online Interpretation Files

NHTSA makes its letters of interpretation available to the public on this webpage. 

An interpretation letter represents the opinion of the Chief Counsel based on the facts of individual cases at the time the letter was written. While these letters may be helpful in determining how the agency might answer a question that another person has if that question is similar to a previously considered question, do not assume that a prior interpretation will necessarily apply to your situation.

  • Your facts may be sufficiently different from those presented in prior interpretations, such that the agency's answer to you might be different from the answer in the prior interpretation letter;
  • Your situation may be completely new to the agency and not addressed in an existing interpretation letter;
  • The agency's safety standards or regulations may have changed since the prior interpretation letter was written so that the agency's prior interpretation no longer applies; or
  • Some combination of the above, or other, factors.

Searching NHTSA’s Online Interpretation Files

Before beginning a search, it’s important to understand how this online search works. Below we provide some examples of searches you can run. In some cases, the search results may include words similar to what you searched because it utilizes a fuzzy search algorithm.

Single word search

 Example: car
 Result: Any document containing that word.

Multiple word search

 Example: car seat requirements
 Result: Any document containing any of these words.

Connector word search

 Example: car AND seat AND requirements
 Result: Any document containing all of these words.

 Note: Search operators such as AND or OR must be in all capital letters.

Phrase in double quotes

 Example: "headlamp function"
 Result: Any document with that phrase.

Conjunctive search

Example: functionally AND minima
Result: Any document with both of those words.

Wildcard

Example: headl*
Result: Any document with a word beginning with those letters (e.g., headlamp, headlight, headlamps).

Example: no*compl*
Result: Any document beginning with the letters “no” followed by the letters “compl” (e.g., noncompliance, non-complying).

Not

Example: headlamp NOT crash
Result: Any document containing the word “headlamp” and not the word “crash.”

Complex searches

You can combine search operators to write more targeted searches.

Note: The database does not currently support phrase searches with wildcards (e.g., “make* inoperative”). 

Example: Headl* AND (supplement* OR auxiliary OR impair*)
Result: Any document containing words that are variants of “headlamp” (headlamp, headlights, etc.) and also containing a variant of “supplement” (supplement, supplemental, etc.) or “impair” (impair, impairment, etc.) or the word “auxiliary.”

Search Tool

NHTSA's Interpretation Files Search



Displaying 13671 - 13680 of 16510
Interpretations Date
 search results table

ID: 9544

Open

Mr. Bob Carver
Product Engineering
Wayne Wheeled Vehicles
13311 Industrial Parkway
Marysville, OH 43040

Dear Mr. Carver:

This responds to your letter of January 8, 1994, asking two questions concerning a recent amendment to Standard No. 217, Bus Emergency Exits and Window Retention and Release (57 FR 49413; November 2, 1992). Your questions and the response to each follow.

1.There's some confusion here in our engineering department regarding the interpretation of the "Daylight Opening" and "Unobstructed Opening" as it applies to the new side emergency door specification in FMVSS 217. Page 2 shows the allowable obstruction and the context in which "Daylight Opening" and "Unobstructed Opening" are used. Page 3 shows some measurements of our seats placed according to the "30 cm minimum" shown on page 2. Page 4 shows four different interpretations of the "Unobstructed Opening" area. Depending on the interpretation, between 9 and 15 people may be accommodated by a side emergency door. My question is this: of the four possibilities shown, which definition of the "Unobstructed Opening" area is correct? Mr. Hott indicated definition 4.

The term "daylight opening" is defined in the Final Rule as "the maximum unobstructed opening of an emergency exit when viewed from a direction perpendicular to the plane of the opening." An obstruction in this context would include any obstacle or object that would block, obscure, or interfere with, in any way, access to that exit when opened. In determining the "maximum unobstructed opening of an emergency exit," we would subtract, from the total area of the opening, the area of any portions of the opening that cannot be used for exit purposes as a result of the obstruction. The area measurements would be taken when viewed from a direction perpendicular to the plane of the opening.

Your question specifically concerns how the "maximum unobstructed opening" of a side door is measured when the opening is partially obstructed by a seat. In the case of the illustrated door exit, occupants would use the exit by movement along the floor. This would be considered in determining the extent of an obstruction. None of the four examples you enclosed with your letter correctly illustrates the area that would be credited for the illustrated exit. The following regions would not be credited for this exit: (1) the area visually obstructed by the seat; (2) your region A2, an area bounded by a horizontal line tangent to the top of the seat back, a vertical line tangent to the rearmost portion of the top of the seat, the upper edge of the door opening, and the edge of the door forward of the seat; (3) your region A5, an area bounded by the seat back, a horizontal line tangent to the top of the seat back, and the edge of the door forward of the seat; and (4) your region A8, an area bounded by the seat leg, the floor, the lower edge of the seat bottom, and the edge of the door forward of the seat. Because the seat would make the last three regions unusable as exit space for a person traveling along the floor of the bus towards the exit, they would not be credited for that exit.

You should be aware that the agency published a notice of proposed rulemaking to amend Standard No. 217 on December 1, 1993 (58 FR 63321). The notice proposed two alternate means for determining the maximum amount of area that will be credited for all types of emergency exits on school buses. The agency is currently reviewing the comments received in response to this notice. I am enclosing a copy of this notice.

2.Here is an excerpt from FMVSS 217 S5.5.3(a):

"Each school bus ....shall have the designation "Emergency Door" or "Emergency Exit" as appropriate, .... For emergency exit doors, the designation shall be located at the top of, or directly above, the emergency exit door on both the inside and outside surfaces of the bus..... For emergency window exits, the designation shall be located at the top of, or directly above, or at the bottom of the emergency window exit on both the inside and outside surfaces of the bus."

I've seen a two-sided sticker used by other bus manufacturers. It is applied on the inside surface of a window and the same image "Emergency Door" or "Emergency Exit" can be read from both inside and outside the bus. Is it permissible for us to use this sort of decal, assuming it meets all other (i.e., FMVSS 302)?

The answer to your question is yes. The agency addressed this issue in an October 2, 1978, letter to Mr. E.M. Ryan of Ward Industries, Inc. I am enclosing a copy of this letter.

I hope you find this information helpful. If you have any other questions, please contact Walter Myers of my staff at this address or by phone at (202) 366-2992.

Sincerely,

John Womack Acting Chief Counsel

Enclosures

ref:217 d:3/24/94

1994

ID: 9549

Open

Mr. Thomas D. Turner
Manager, Engineering Services
Blue Bird Body Company
P.O. Box 937
Fort Valley, GA 31030

Dear Mr. Turner:

This responds to your letter of January 6, 1994, asking several questions concerning a recent amendment to Standard No. 217, Bus Emergency Exits and Window Retention and Release (57 FR 49413; November 2, 1992). Our response to each of your questions follows.

1.Your first question requested confirmation that a left side emergency exit door required by S5.2.3.1(a)(2)(i) would meet the location requirements of S5.2.3.1(a)(2)(i) if it is located in the center one- half of the passenger compartment.

Your question concerns the first required additional emergency exit installed on a bus with a rear emergency exit door. Section S5.2.3.2(a)(2) requires this exit to be a side emergency exit door "located on the left side of the bus and as near as practicable to the midpoint of the passenger compartment." Locating the door or the 12-inch required aisle opening for the door in the center one-half of the passenger compartment would not ensure compliance with this requirement. This is because it may be possible to locate a door in the center one-half without locating the exit "as near as practicable to the midpoint of the passenger compartment." In determining the permissible location for this exit, you should determine where the exit would be located if it was located at the midpoint of the passenger compartment. If it is not practicable to locate the exit there, you should move the door only as far as necessary for a practicable location.

2.Your second question requested confirmation that there are no fore and aft location requirements for side emergency exit doors other than the requirements for a left side emergency exit door required by S5.2.3.1(a)(2)(i).

You are correct. Except for a left side emergency exit door installed as the first additional emergency exit on a bus with a rear emergency door, the only location requirements for side emergency exit doors concern the side of the bus on which the exit must be located. I have attached for your information an appendix which lists all the location requirements for additional emergency exits.

3.Your third question requested confirmation that all side emergency exit doors, including any voluntarily installed, are required to comply with the requirements of the new final rule, including the seat placement requirements in S5.4.2.1(b).

You are correct. Your letter referred to a March 9, 1977 interpretation that voluntarily installed side emergency exit doors were not required to meet the school bus requirements, but were required to meet the non-school bus requirements. Previously, the school bus emergency exit door requirements in Standard No. 217 referred to "the emergency door." At that time school buses were required to have either one rear emergency exit door or one side emergency exit door and one rear push-out window. Thus, any school bus was required to have only one emergency exit door. The reference to "the emergency door" was to the required door.

In the recent amendments to Standard No. 217, some of the performance requirements for emergency exits apply to "each" emergency exit. See, for example, S5.4.2.1(b). This change in the language extends these requirements to any emergency exit door in a school bus. Other requirements apply to "required" emergency exits. See, for example, S5.5.3(c). These requirements do not apply to voluntarily installed emergency exits.

I hope you find this information helpful. If you have any other questions, please contact Walter Myers of my staff at this address or by phone at (202) 366-2992.

Sincerely,

John Womack Acting Chief Counsel

Enclosures

ref:217 d:4/14/94

1994

ID: 9556

Open

Mr. Adam A. Freund
Manager, Testing Services
Standards Testing Laboratories, Inc.
Post Office Box 592
1845 Harsh Avenue, S.E.
Massillon, OH 44648

Dear Mr. Freund:

This responds to your letter addressed to the attention of Walter Myers of my staff in which you asked whether Table II of Federal Motor Vehicle Safety Standard (FMVSS) No. 119, New pneumatic tires for vehicles other than passenger cars, contains certain errors.

You pointed out in your letter that Table I of FMVSS 119 specifies a plunger diameter of 5/16 inch for motorcycles, and 3/4 inch for 12-inch or smaller rims other than motorcycles. Table II, on the other hand, leaves blank the plunger diameter space in the motorcycle column, but lists 5/16 inch plunger diameter in the 12-inch or smaller rim column. You indicated your belief that the inconsistency is due to a typographical error in those columns of Table II and asked us to confirm your interpretation.

Your observation is correct. A November 13, 1973 rule adopting Tables I and II (38 FR 31299) (copy enclosed) specifies the 5/16-inch diameter plunger for motorcycle tires, and the 3/4- inch diameter plunger for 12-inch or smaller tires and 17.5- inch or smaller light truck tubeless tires. Accordingly, the plunger diameter for the motorcycle column in Table II should read 5/16. Similarly, the 12-inch or smaller column in the current Table II is in error in specifying a plunger diameter of 5/16 inch. The correct plunger diameter for that column in Table II should be 3/4 inch to correspond with the plunger diameter specified for 12-inch or smaller rims in Table I.

Thank you for bringing this error to our attention. The agency will issue a correction to avoid any further confusion.

Sincerely,

John Womack Acting Chief Counsel ref:119 d:4/12/94

1994

ID: 9559

Open

Mr. Richard Kreutziger
Executive Director
New York State Bus Distributor Ass'n, Inc.
102 Grace Street
Penn Yan, NY 14527

Dear Mr. Kreutziger:

This responds to your FAX of January 12, 1994, requesting an information on the extent to which a state can adopt requirements for school buses which exceed the Federal motor vehicle safety standards. This also responds to your FAX of February 14, 1994, requesting an explanation of the location requirements for a side emergency door exit in Standard No. 217, Bus Emergency Exits and Window Retention and Release (as amended at 57 FR 49413; November 2, 1992).

Your January 12, 1994 FAX requested clarification of when a state could impose requirements on school buses which exceeded the requirements of the Federal motor vehicle safety standards (FMVSS). Specifically, you asked whether the state could impose such requirements on (1) a public school and (2) a contractor providing transportation for a public school. Section 103(d) of the National Traffic and Motor Vehicle Safety Act (the Safety Act; 15 U.S.C. 1392(d)) provides that:

Whenever a Federal motor vehicle safety standard ... is in effect, no State or political subdivision of a State shall have any authority either to establish, or to continue in effect, with respect to any motor vehicle or item of motor vehicle equipment any safety standard applicable to the same aspect of performance of such vehicle or item of equipment which is not identical to the Federal standard. Nothing in this section shall be construed to prevent ... any State or political subdivision thereof from establishing a safety requirement applicable to motor vehicles or motor vehicle equipment procured for its own use if such requirement imposes a higher standard than that required to comply with the otherwise applicable Federal standard.

Section 103(d) preempts state requirements for school buses covering the same aspect of performance as an applicable FMVSS that are different from the applicable FMVSS, except to the extent that the requirements impose a higher level of performance and apply only to vehicles procured for the State's use. A state law imposing higher requirements would be preempted under 103(d) to the extent that the law requires all school buses manufactured for use in the state to comply with the law. The law would not be preempted to the extent that it applies to public school buses. In addition, the agency has previously interpreted the phrase "vehicles procured for (the State's) own use" to include public school buses and school buses operated and owned by a private contractor under contract to transport children to and from public school. See, for example, February 20, 1987 letter to Mr. Martin Chauvin (copy enclosed).

Your February 14, 1994 FAX asked whether the November 2 final rule permits a right side emergency exit door to be to the rear of the passenger compartment. The answer is yes. Except for a left side emergency exit door installed as the first additional emergency exit on a bus with a rear emergency door, there are no fore and aft location requirements for side emergency exit doors. I have attached for your information an appendix which lists all the location requirements for additional emergency exits.

I hope you find this information helpful. If you have any other questions, please contact us at this address or by phone at (202) 366-2992.

Sincerely,

John Womack Acting Chief Counsel

Enclosures

ref:VSA#217 d:3/28/94

1994

ID: 9560

Open

Maurice Hannigan, Commissioner
Department of California Highway Patrol
P.O. Box 942898
Sacramento, CA 94298-001

Dear Mr. Hannigan:

It has come to our attention that a misunderstanding has arisen about a letter we issued on March 31, 1993 to W.C. Burke of your Department. That letter explained the marking responsibilities of a person who installs replacement glass (referred to as glazing in the Federal standard) under section S6.4 of Federal motor vehicle safety standard No. 205, Glazing Materials (49 CFR 571.205, copy enclosed.) On January 12, 1994, Mr. Clarke Harper of this agency's Office of Vehicle Safety Standards and Mr. Marvin Shaw of my staff contacted Mr. Walter Burke and Mr. Kyle Larson of CHP to discuss this matter. This letter is a follow up to that discussion.

Based on its understanding of the March 1993 letter, CHP is requiring installers to mark replacement glazing with a number (which the agency refers to as a manufacturer's code mark) and has directed school districts to tell installers of glass to contact NHTSA "[t]o obtain a number as required by [Standard No. 205]." Standard No. 205 does not require the typical aftermarket installer to obtain such a number from the agency.

We explained in the March 1993 letter that a person who cuts glazing (i.e., a typical installer of aftermarket glazing) must mark the piece with the following information required by section 6 of American National Standard (ANS) Z26: (1) the words "American National Standard" or the characters "AS," (2) a number identifying the item of glazing, (3) a model number assigned by the manufacturer that identifies the type of construction of the glazing material, and (4) the manufacturer's distinctive designation or trademark.

Mr. Larson stated that he was under the impression that "(3) a model number assigned by the manufacturer" was a number assigned by NHTSA. As we explained to him, this is not the case. The installer devises his own model number. The only number assigned by NHTSA under Standard No. 205 is the code mark assigned to a manufacturer who "fabricates, laminates, or tempers the glazing material" (known as a "prime glazing material manufacturer").

We hope that this clarifies our earlier letter on this subject. If you have any other questions, please contact Mr. Shaw at (202) 366-2992.

Sincerely,

John Womack Acting Chief Counsel

ref:205 d:2/9/94

1994

ID: 9588

Open

Mr. Allan Garman
M.F. Bank & Co., Inc.
2505 W. 2nd Avenue
Suite 14
Denver, CO 80219-1655

Dear Mr. Garman:

This responds to your letter and telephone call asking several questions about the responsibilities of various parties after child restraint systems have been involved in a collision and fire during transit from the manufacturer (Gerry Products) to a retail outlet (Toys R Us). I apologize for the delay in responding.

You indicate in your letter that the child restraint manufacturer, Gerry Baby Products, has determined that the DOT certification on the child restraints is no longer valid because the restraints were subjected to potential stress by the impact of the truck accident. We understand from your letter that M.F. Bank is storing the child restraint systems damaged in transit, and is prepared to liquidate the stock if directed to do so by the insurer of the transit company. However, the insurer has asked that M.F. Bank ask this agency whether the child restraint systems involved in the loss can be sold as salvage to the public. You state your belief that the systems are salvagable because they did not experience structural damage in the incident.

By way of background information, the National Traffic and Motor Vehicle Safety Act (15 U.S.C. sections 1381 et seq.) authorizes the National Highway Traffic Safety Administration (NHTSA) to issue Federal motor vehicle safety standards (FMVSSs) for new motor vehicles and new items of motor vehicle equipment. Under that authority, NHTSA issued FMVSS No. 213, "Child Restraint Systems" (49 CFR '571.213) to reduce the number of children killed or injured in motor vehicle crashes and in aircraft. Section 108(a)(1)(A) of the Safety Act prohibits any person from manufacturing for sale or selling any new item of equipment that does not conform to all applicable FMVSSs or is not covered by a certification of compliance with the applicable FMVSSs. Thus, each new child restraint system must comply with FMVSS No. 213 and must be certified as complying with that standard when it is sold.

You first ask whether Federal law would prohibit the sale of the child restraint systems as salvage. The answer is yes, since according to your letter and telephone call, Gerry has indicated that its certification is no longer valid, and has thereby withdrawn the certification. If the child seats are not certified, selling them would violate '108(a)(1)(A). Section 109 of the Act provides any violation of Section 108 is punishable by civil penalties of up to $1,000 per violation, up to a maximum of $800,000 for a series of related violations.

You ask in your telephone call whether Federal law prohibits Gerry from concluding that the certification remains valid. If your question is whether the Safety Act or our regulations require Gerry to withdraw the certification simply because the seats were involved in an incident, the answer is no. However, '108(a)(1)(C) of the Safety Act prohibits any person from certifying that a child restraint system complies with Standard 213 if that person, in the exercise of due care, has reason to know that the certificate is false or misleading in a material respect. Gerry is therefore required by the Safety Act to withdraw the certification of the unsold seats if it believes the certification is invalid. If a manufacturer determines, for any reason, that the unsold seats do not comply, NHTSA will not second guess the decision to withdraw the certification.

Finally, you ask if it would be possible for NHTSA to send someone to your warehouse to inspect the child restraint systems to determine whether the systems comply with FMVSS No. 213. The answer is no; NHTSA does not inspect products for compliance outside the context of its enforcement activities. The Safety Act establishes a self-certification system under which child restraint manufacturers are responsible for ensuring that their products comply with FMVSS No. 213. NHTSA does not approve, endorse, or give assurances of compliance of any product.

I hope this information answers your questions. If you need further information, please feel free to contact Ms. Deirdre Fujita of my staff at (202) 366-2992.

Sincerely,

John Womack Acting Chief Counsel

ref:213#VSA d:5/31/94

1994

ID: 9589

Open

Mr. James M. Keitges
President
Native American Motorcycle Co.
P.O. Box 4287
Omaha, NE 68104

Dear Mr. Keitges:

This is in reply to your letter of January 14, 1994, in which you ask to be provided the statement "that once the company has complied with all Federal NHTSA statutes, regulations, and standards, then the company has also complied with the State and Local requirements as applicable to NHTSA."

It is not possible to provide you with a statement in this form. We are unaware of any State and local requirements that are literally "applicable to NHTSA." However, there may be state and local laws that require compliance with the Federal motor vehicle safety standards, issued by NHTSA, in order for vehicles to be sold or registered for use on state and local roads. We believe it likely that this is your concern, and we will take this opportunity to explain the relationship between Federal and State or local requirements.

Section 103(d) of the National Traffic and Motor Vehicle Safety Act (l5 U.S.C. 1392(d)), in effect, allows a State or a political subdivision of a State to enact a safety standard covering the same aspect of performance as a NHTSA Federal motor vehicle safety standard if it is identical to the NHTSA standard. A State or local standard cannot impose a higher level of performance than a NHTSA standard, except for vehicles procured for use by the State or the political subdivision. Further, a State or a subdivision is specifically permitted to enforce its own identical safety standard. Finally, State or local standards are permitted in areas of performance where there is no NHTSA standard, such as horns and fog lamps.

Section 114 of the Act (15 U.S.C. 1403) requires each motor vehicle to bear its manufacturer's permanently affixed certification of compliance with all applicable Federal motor vehicle safety standards. This certification raises the presumption that the vehicle, in fact, conforms with those standards. If a State or local law is worded so as to require compliance with all Federal motor vehicle safety standards as a condition of vehicle sale or registration, then the manufacturer's certification should be accepted as fulfilling this State or local requirement. We believe, however, that in spite of the certification, a vehicle could be rejected as not in conformance with Federal requirements within the meaning of State or local law if the nonconformance was manifest on its face (e.g., failure of a new passenger car to be equipped with a center highmounted stop lamp) in spite of the facts that a State cannot enforce a Federal standard, and that neither the manufacturer nor NHTSA may have made a formal determination of noncompliance.

If the State or local law is worded so as to require compliance with all State or local requirements as a condition of sale or registration, the manufacturer's certification may be accepted as indicating compliance with all identical State or local requirements if the governing authority so chooses, but obviously the certification could not cover compliance with State or local requirements in areas not covered by the Federal safety standards.

We hope that this explanation is useful to you, and will be glad to answer any further questions you may have.

Sincerely,

John Womack Acting Chief Counsel

ref:VSA d.2/3/94

1994

ID: 9590

Open

Mr. Donald F. Lett
Lett Electronics Company
410 North Plum
Hutchinson, KS 67501

Dear Mr. Lett:

This responds to your letter to me in which you asked whether any "pre-necessary authorization" is needed for molding white sidewalls onto existing passenger car tires. We assume "pre- necessary authorization" means this agency's prior approval or permission to modify the tires in the manner you propose.

You explained in your letter that you intend to modify existing radial passenger car blackwall tires by grinding a recess into one sidewall between 1/8 and 3/16 inches deep by 2 inches wide, then vulcanizing white rubber into that recess to transform a "D.O.T. approved radial blackwall tire" into a white sidewall tire. You would then market those tires, as modified, for classic cars of the 1955-1960 era.

By way of background, the National Traffic and Motor Vehicle Safety Act of 1966, 15 U.S.C. 1381, et seq. (Safety Act), gives the National Highway Traffic Safety Administration (NHTSA) the authority to issue Federal motor vehicle safety standards (FMVSS) applicable to new motor vehicles and new items of motor vehicle equipment. Tires are considered motor vehicle equipment.

The Safety Act establishes a self-certification system in which vehicle and equipment manufacturers certify that their products comply with all applicable FMVSSs in effect on the date of manufacture. Because of this self-certification system, neither NHTSA nor the Department of Transportation (DOT) approves, endorses, certifies, or gives assurances of compliance of any product. Rather, NHTSA enforces its standards by testing products in accordance with the test procedures set forth in applicable FMVSSs. If the product meets the requirements of the standard, no further action is taken. If the product fails to comply, the manufacturer must notify the purchasers of the product and remedy the noncompliance without charge to the purchaser(s). Failure to comply with any FMVSS can also result in civil penalties of up to $1,000 per violation, up to a maximum of $800,000 for a series of related violations.

We assume from your letter that you propose to modify new radial passenger car tires. Whether the process you described is permissible depends on whether it adversely affects the tire's compliance with FMVSS No. 109, New Pneumatic Tires (copy enclosed). This standard specifies the performance requirements applicable to passenger car tires, which include tubeless tire resistance to bead unseating, tire strength, tire endurance, and high speed performance.

It does not appear that radial tires can be modified as you propose and still meet the requirements of Standard 109. The average radial tire sidewall is approximately 3/16 inch thick at the shoulder, gradually increasing to approximately 1/2 inch where the sidewall meets the bead. The radial sidewall is unsupported by cords, belts, or other material contributing to the strength of that sidewall. To achieve a 2 inch whitewall, at least some of the whitewall would extend into the tire shoulder. Therefore, cutting into a radial tire sidewall at the shoulder to a depth of 3/16 inch would cut through the sidewall. Cutting into the sidewall at the shoulder to a depth of 1/8 inch would leave approximately 1/16 inch of rubber on the shoulder of the tire. That would, obviously, have the effect of destroying the tire.

Section 108(a)(1)(A) of the Safety Act, 15 U.S.C. 1397 (a)(1)(A), prohibits any person from manufacturing or selling any new item of equipment that does not conform to all applicable FMVSSs. A new noncomplying tire that is sold to a retail customer would constitute a violation of 108(a)(1)(A), and is subject to the recall and civil penalties described above. In addition, 108(a)(2)(A) of the Safety Act, 15 U.S.C. 1397(a)(2)(A), prohibits a manufacturer, distributor, dealer, or motor vehicle repair business from knowingly rendering inoperative any safety device or element of design installed on or in a motor vehicle or item of motor vehicle equipment in compliance with a Federal motor vehicle safety standard. Accordingly, modifying previously-complying tires by removing them from compliance with the strength requirements of FMVSS 109 could violate 108(a)(2)(A), again subjecting the violator to the civil penalties described above.

Standard No. 109 also requires that certain information be molded into or onto the sidewalls of tires in certain specified locations and that the letters "DOT" appear on each tire sidewall to indicate the manufacturer's certification that the tire complies with all applicable FMVSSs. In addition, the Uniform Tire Quality Grading Standards (UTQGS), 49 CFR Part 575.104, provides that the ratings required by that section will be molded onto or into the sidewalls of tires. Therefore, if the modification you propose obliterates or removes any of the required labeling, that could violate FMVSS 109 and the UTQGS, again subjecting the violator to penalties.

In addition to the safety implications of grinding and filling recesses in tires, we also note that the suspension systems of older motor vehicles may not be compatible with radial tires. The handling and stability of those vehicles could be adversely affected by mounting radial tires on them, or by the mixing radial and bias ply tires, without appropriate modifications to their suspension systems.

Finally, I note that you used the term "previously D.O.T. approved" tire in your letter. As explained above, NHTSA does not use that term because neither NHTSA nor the Department of Transportation "approves" tires or any other motor vehicle product. We assume that by using that expression you mean that the tires you select for modification contain the "DOT" code that signify the manufacturer's, not NHTSA's, certification. Nevertheless, since the meaning of the term is unclear and might be misleading to consumers, we ask that you not use that term in any of your promotional materials.

I hope this information is helpful to you. Should you have any further questions or need any additional information, please feel free to contact Walter Myers of my staff at this address or at (202) 366-2992.

Sincerely,

John Womack Acting Chief Counsel

Enclosure

ref:109#110#575 d:5/18/94

1994

ID: 9595

Open

Mr. Don Vierimaa
Truck Trailer Manufacturers Association
1020 Princess Street
Alexandria, VA 22314

Dear Mr. Vierimaa:

This responds to your FAX of January 11, 1994, to Pat Boyd of this agency requesting an interpretation of the trailer conspicuity requirements of Standard No. 108. In the future, please address your requests for interpretations to the Chief Counsel.

You have asked "may a manufacturer install a 4 inch (100 mm) wide retrofrelective sheeting instead of 2 inch (50 mm) sheeting on the side of new trailers?"

Paragraph S5.7.1.3(d) of Standard No. 108 states that retroreflective sheeting shall have a width of 50 mm (Grade DOT-C2), 75 mm (Grade DOT-C3), or 100 mm (Grade DOT-C4). Paragraph S5.7.1.4.2(a), as amended on October 6, 1993 (58 FR 52021 at 52026), sets forth the requirements for application of retroreflective sheeting to the side of trailers. Without elaboration, it simply identifies it as "a strip of sheeting." This means that the manufacturer of the trailer is permitted his choice of Grade DOT-C2, -C3, or -C4 material. Therefore, a manufacturer may install sheeting that has a width of 100 mm on the side of a trailer.

Sincerely,

John Womack Acting Chief Counsel

ref:108 d.2/7/94

1994

ID: 9611

Open

Mr. C.N. Littler
Motor Coach Industries
Administrator Regulatory Affairs
1558 Wilson Place
Winnipeg, Manitoba R3T 0Y4
CANADA

Dear Mr. Littler:

This responds to your letter concerning whether a New York State law addressing the in-use stopping ability of privately owned motor coaches is preempted by Federal law. I apologize for the delay in our response. The New York law states that a vehicle must be capable of stopping "at a rate of deceleration equivalent to a stop within 22.2 feet from a speed of 20 miles per hour." You believe that '103(d) of the National Traffic and Motor Vehicle Safety Act ("Safety Act") preempts the New York law, since the state law is not identical to Federal motor vehicle safety standard No. 121, Air Brake Systems. Please note that the Safety Act has been codified at 49 U.S.C. 30101 et seq. and that the citation for 103(d) is now 49 U.S.C. '30103.

As explained below, Standard No. 121 currently does not have stopping distance requirements in effect; therefore, the New York law is not currently preempted by a Federal safety standard. Nevertheless, the agency has issued a proposal to reinstate stopping distance requirements in Standard No. 121. (58 FR 11003, February 23, 1993). If the agency issues a final rule to reinstate stopping distances, then any more stringent requirements in the New York law (addressing the same aspects of performance as Standard No. 121) would be preempted.

Title 49 U.S.C. '30103 states:

Whenever a Federal motor vehicle safety standard ... is in effect, no State or political subdivision of a State shall have any authority either to establish, or to continue in effect, with respect to any motor vehicle or item of motor vehicle equipment any safety standard applicable to the same aspect of performance of such vehicle or item of equipment which is not identical to the Federal standard.

That provision preempts New York's law if there is a Federal safety standard in effect, the state law covers the same aspect of performance as that Federal standard, and the State law is not identical to the Federal safety standard. While you are correct that Standard No. 121 refers to stopping performance in S5.3.1, you apparently were not aware of a provision in S3 that states

Notwithstanding any language to the contrary, sections S5.3.1, S5.3.1.1, S5.3.2, S5.3.2.1, S5.3.2.2, S5.7.1, S5.7.3(a) and S5.7.3(b) of this standard are not applicable to trucks and trailers, and section S5.3.1 of this standard is not applicable to buses.

The agency amended the standard to include this provision as the result of a ruling in PACCAR v. NHTSA, 573 F.2d 632, (9th Cir. 1978), cert. denied, 439 U.S. 862 (1978), in which a Federal Court of Appeals invalidated Standard No. 121's stopping distance requirements until the agency obtains "more probative and convincing data evidencing the reliability and safety of vehicles that are equipped with antilock." While the provision did not originally cover buses other than school buses, NHTSA extended the provision to non-school buses in 1987. See 52 FR 20602. Because there are no Federal stopping distance requirements in effect, the New York law is not preempted.

As noted above, NHTSA has issued a notice proposing to reinstate stopping distance requirements for air braked vehicles. The agency is currently reviewing comments to that proposal, and may issue a final rule reinstating stopping distance requirements. If the agency decides to amend Standard No. 121 to include such requirements, then any more stringent requirements in the New York law (addressing the same aspects of performance as Standard No. 121) would be preempted.

I note that the New York law applies to vehicles in use, while Standard No. 121 applies to new vehicles. In general, State laws governing the operation of vehicles are not preempted by inconsistent Federal motor vehicle safety standards unless the State law is more stringent than the Federal standard (with respect to the same aspect of performance). A more stringent law would be preempted, since it would preclude the sale of vehicles that comply with Federal standards.

I also note that the in-use braking performance of many motor coaches is regulated by the Federal Highway Administration. We have referred your letter to that agency's Office of Motor Carrier Standards concerning the issue of whether its regulations preempt the New York law.

I hope this information is helpful. If you have any questions about NHTSA's safety standards, please feel free to contact Marvin Shaw at this address or by telephone at (202) 366-2992. If you wish to contact someone in the Federal Highway Administration's Office of Chief Counsel concerning the motor carrier standards, please call Charles Medalen at (202) 366- 1354.

Sincerely,

John Womack Acting Chief Counsel

Enclosure

ref:121#103(d) d:9/7/94

1994

Request an Interpretation

You may email your request to Interpretations.NHTSA@dot.gov or send your request in hard copy to:

The Chief Counsel
National Highway Traffic Safety Administration, W41-326
U.S. Department of Transportation
1200 New Jersey Avenue SE
Washington, DC 20590

If you want to talk to someone at NHTSA about what a request for interpretation should include, call the Office of the Chief Counsel at 202-366-2992.

Please note that NHTSA’s response will be made available in this online database, and that the incoming interpretation request may also be made publicly available.