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
Interpretations | Date |
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ID: 2669rbmOpenMr. Charlie Steffens Dear Mr. Steffens: This responds to your letter requesting an interpretation of the advanced air bag requirements of Federal Motor Vehicle Safety Standard No. 208, Occupant crash protection (FMVSS No. 208). On May 12, 2000, the National Highway Traffic Safety Administration (NHTSA) published a final rule in the Federal Register (65 FR 30680) requiring advanced air bags in all passenger cars, multi-purpose vehicles, light trucks and buses with a gross vehicle weight rating (GVWR) of 8,500 lb or less. The phase-in for these new requirements begins September 1, 2003. That final rule established new, advanced air bag performance requirements to minimize the risk of injury to children, as well as new requirements to enhance protection of small and mid-size adults. The requirements in S19, S21, and S23 are designed to minimize the risk that air bags pose to infants and small children. S19 provides manufacturers with two different options for complying with the standard (low risk deployment or automatic suppression), while S21 and S23 provide three options (low risk deployment, automatic suppression, or dynamic automatic suppression). Your first question is related to the infant low risk deployment option while your three other questions are related to the interrelationship between the compliance options. I am pleased to provide a response. You first request an interpretation of the requirement set forth in S19 and the test procedure provided in S20.4, relating to the low risk deployment option for infants. Specifically, you characterize the requirements of S20.4 as follows. "For S20.4.9, if the subject vehicle were equipped with any type of occupant sensing system that was The requirements for the infant low risk deployment option are found at S19.3, which states that "each vehicle shall meet the injury criteria specified in S19.4 of this standard when the passenger air bag is deployed in accordance with the procedures specified in S20.4." The low risk deployment option is designed to address injuries that can result when an infant is placed very close to the air bag. The risk of being directly above or adjacent to the air bag is particularly high for infants because child restraints, when placed in their rear-facing mode, will always place an infant's head close to the dashboard. A poorly installed forward-facing child seat also creates a risk, because the restraint can slide or flip forward during a crash. S20.4 specifies several conditions for testing the deploying air bag. First, the manufacturer must assure compliance to S19.3 using any child restraint listed in subparts B and C of Appendix A to the standard. Restraints listed in subpart A (car beds) need not be tested because these restraints are not designed to be rear facing. For purposes of S19.3, the air bag is only tested with the child restraints in their rear-facing condition. This represents the worst case injury scenario. Under the specified test conditions, the vehicle seat is moved as far forward as possible, while avoiding contact with the vehicle interior. This is done to ensure that the dummy's head is placed as close to the deploying air bag as possible. The air bag is only tested with the child restraint in a belted condition. The air bag is deployed at whatever level of force and combination of stages that would deploy in any rigid barrier crash up to 64 km/h (40 mph) when a child or test dummy is positioned in a restraint as specified in the test procedure, except that the vehicle seat may be at any seat track position. This level is determined by running an indicant test, as described in S20.4.9, at impact speeds up to 40 mph with a dummy-occupied restraint installed in the passenger seat. [1] When NHTSA runs a compliance test on a vehicle certified to S19.3, it will only deploy the air bag at the level and, if equipped with a multi-stage inflator, with the combination of stages, that would deploy in the specified indicant test. Accordingly, vehicle manufacturers that certify to the low risk deployment option will need to ensure that their sensing systems are sufficiently robust to detect the presence of an infant in any one of the child restraints listed in subparts B or C of Appendix A. If only a "low output" air bag deploys in the indicant test, NHTSA will not deploy a "high output" air bag simply because the "high output" air bag is placed in the vehicle for other occupants who may be seated in the passenger seat. Such an approach would have the effect of preventing vehicle manufacturers from using sensing technology to identify the presence of an infant at higher speeds. Your next two questions relate to how the different compliance options relate to one another. Specifically, you ask if "the intent of the regulation... mean[s] that at compliance strategy needs to be chosen for each occupant size [i.e., the 1-year-old, the 3-yer-old, and the 6-year-old], but that a different strategy can be employed for each." You then ask if it is "possible to comply with ... the regulation using multiple compliance methods within an occupant size grouping using a logical subgrouping. For instance, could a system use deployment suppression for certifying the 3 and 6-year-old children in child seats and low risk deployment for the 3 and 6-year-old children not in child restraints?" A vehicle manufacturer must certify to one of the compliance options in S19, S21, and S23. You first ask whether a different compliance option may be used for each group of children addressed by the regulation. The answer is yes. Each set of compliance options specified for a particular group of children is unique to that group. Accordingly, a manufacturer could choose to use automatic suppression to meet the infant and three year old requirements, but low risk deployment or dynamic automatic suppression for the six year old requirements. [2] However, within a given age group, a manufacturer may not choose to certify some portion of the population to one option and another portion of the population to another option. This would result in a unique compliance option that may fail to address all conditions contemplated by each option. For example, it is not acceptable to claim certification by meeting only one of the two low risk deployment positions for the three year old and 50 percent of the suppression positions. A system needs to meet one of the two options in its entirety. A customized compliance option, where the manufacturer used part of different options, but not all of any option, would create a unique compliance scheme that was never contemplated by the agency in determining how best to meet the need for safety without imposing unreasonable constraints on vehicle manufacturers. We note that in the example you provided in your letter, whereby a manufacturer would "use deployment suppression for certifying the 3 and 6-year-old children in child seats and low risk deployment for the 3 and 6-year-old children not in restraints" would be a compliant system that could be fully certified to the low risk deployment option, but not to the suppression option. Nothing in the rule prohibits manufacturers from using such a design philosophy. The deployment strategies related to children restrained in child restraints would remain within the manufacturer's discretion. Your final question asks whether a manufacturer could use both low risk deployment and automatic suppression systems as a system redundancy. You state: "Assume that a sensing system met all of the conditions... for the RFIS low risk requirement. Suppose the sensing system also had the further capability to classify and suppress for certain tested situations. The system would be certified to meet all the low risk deployment requirements, however under certain conditions the system would suppress the airbag instead of deploying at low level because of this redundant capability. TRW believes a system of this type would comply with FMVSS 208 based upon similar NHTSA interpretations using additional or redundant safety equipment." Your understanding is correct. Manufacturers may choose to use multiple technologies to address real world risk, without certifying to more than one compliance option. NHTSA specifically addressed this possibility in the May 2000 final rule (65 FR 30680, 30710). For example, a manufacturer may decide to use both low risk deployment and occupant sensing technologies for the six year old because it has concerns that the occupant sensing technology is insufficiently robust for all real world conditions, even though it may meet all the conditions specified in the test procedure. In such an instance, the manufacturer could certify to S23 using either the low risk deployment option or the automatic suppression option, even though in actual driving conditions, the air bag may sometimes deploy when an occupant the size of a 6-year-old is seated in the passenger seat. However, the manufacturer must choose one of the options for certification. Once it decides which option to certify to, it cannot change its position, even though the vehicle may fully meet the requirements of the other options. See S4.8. We require manufacturers to choose a particular option so that we can conduct compliance testing in an effective and productive manner. I hope this letter addresses your concerns. Please feel free to contact Rebecca MacPherson of my staff at (202) 366-2992 should you have any additional questions. Sincerely, Jacqueline Glassman ref:208 [1] The preamble to the May 2000 final rule states that an indicant test is not required. The statement was made in response to a comment that an indicant test would be required for every child restraint on Appendix A. Multiple indicant tests are not required. It may also be possible that a manufacturer could otherwise ascertain that only a very benign air bag will deploy in the presence of a belted child restraint at any speed. However, NHTSA may choose to run an indicant test to verify that only a benign deployment was possible. [2] Currently dynamic automatic suppression cannot be used to certify to the infant requirements. |
2003 |
ID: 2669yOpen Mr. Ricky Bass Dear Mr. Bass: This is in reply to your letter of August 1, l990. You have asked whether it would be permissible to use a triple lamp cluster, each lamp containing a dual filament bulb, to perform identification and stop lamp functions on cargo tank trucks. The cluster would be mounted not less than l0 feet 6 inches above the road surface. You believe that with this design, the function of the identification lamp "will be intact." In telephone conversations with agency personnel on September ll, l990, you clarified that you would like to have this device installed on all new tank trucks, and installed on vehicles in use when they are returned for extensive repairs. The device is intended to supplement the vehicle's conventional stop lamps. With respect to new tank trucks, Standard No. l08 permits supplementary lighting equipment provided that it does not impair the effectiveness of lighting equipment required by the Standard. The determination of impairment is to be made initially by the truck manufacturer in its certification of compliance with all applicable standards, and if the decision appears to be clearly erroneous, NHTSA will so inform the manufacturer. In the present case, the required lighting devices that concern us are the identification lamps, and the conventional stop lamps. As the triple cluster will continue to be illuminated, though with a somewhat greater intensity in the stop lamp mode, we do not consider that the device would impair the effectiveness of the identification lamps. As for whether the device would impair the effectiveness of the conventional stop lamps, we note that the triple lamp cluster will be located from 126 inches to 156 inches above the road surface. Under Standard No. 108, the conventional stop lamps cannot be located more than 72 inches from the road surface. We judge from the configuration of the tank truck that, in actuality, the lamps will be mounted substantially lower than 72 inches. We raise the possibility that the activation of the supplementary lamps, which are located at such a distance from the conventional ones, could create momentary confusion in a driver immediately following a truck equipped with the device. You also wish to install the device on trucks in use, when they are due for major repairs. The sole Federal restraint upon modifications of this nature is that, when performed by vehicle or equipment manufacturers, distributors, dealers or repair businesses, they do not render inoperative, in whole or in part, any device or element of design installed in accordance with a Federal motor vehicle safety standard. As we understand it, your company would perform these modifications on its own vehicles. Therefore, the prohibition would not come into play. Even if the modifications were done by, for example, a motor vehicle repair business, it would be substituting one type of identification lamp for another. We see no problem with the substitution by itself. However, to the extent that the supplementary stop lamps might impair the effectiveness of the conventional stop lamps on new trucks, their installation by the repair business could be considered as rendering the conventional stop lamps partially inoperative, within the meaning of the statutory prohibition for vehicles in use. Vehicles in use are also subject to the laws of the States in which they are registered and operated. Since we are not conversant with State laws, we suggest that you contact the American Association of Motor Vehicle Administrators, 4600 Wilson Boulevard, Arlington, Va. 22203, for an opinion. Sincerely,
Paul Jackson Rice Chief Counsel /ref:l08 d:9/24/90 |
1990 |
ID: 2670oOpen Mr. Jan Peter Kryger Dear Mr. Kryger: This responds to your letter asking whether any Federal safety standards apply to your product called "Quickwheel" and whether you need approval from the Department of Transportation to market the product. You indicated that Quickwheel is similar to a roller skate and can be placed under a flat tire in a few seconds, enabling the driver to go on to a service station. You stated that the device has three little wheels and has been "thoroughly tested" in Germany. The National Traffic and Motor Vehicle Safety Act (Safety Act) authorizes the National Highway Traffic Safety Administration (NHTSA) to issue safety standards for new motor vehicles and new motor vehicle equipment. All motor vehicles and items of motor vehicle equipment manufactured or imported for sale in the United States must comply with all applicable safety standards. NHTSA does not provide approvals of motor vehicles or equipment. The Safety Act places the responsibility on the manufacturer to ensure that its vehicles or equipment comply with applicable requirements. The following represents our opinion based on the facts provided in your letter. NHTSA does not have any safety standards covering a roller-skate-like device intended to be placed under a flat tire in order to enable the driver to continue driving. However, should a safety-related defect be discovered in your device, whether by the agency or yourself, you as the manufacturer would be required by the Safety Act to notify purchasers and provide a remedy for the defect. While no Federal motor vehicle safety standards apply to Quickwheel, we note that the performance of the device is relevant to safety in many of the same respects as tires, which are covered by safety standards. Given this potential safety significance, we urge you to carefully review whether the testing conducted in Germany covered the full range of real-world driving conditions and experiences that may be encountered by Quickwheel, and if not, to conduct such additional testing and/or analysis as may be necessary to ensure that the product will perform in a safe manner. You also asked for an explanation of the Code of Federal Regulations. You will find such an explanation on the last page of an enclosed information sheet entitled "Information for New Manufacturers of Motor Vehicles and Motor Vehicle Equipment." You may also find other parts of the information sheet to be of interest. Sincerely,
Erika Z. Jones Chief Counsel Enclosure ref:571 d:2/ll/88 |
1970 |
ID: 2670yOpen Mr. and Mrs. Albert J. Fasel Dear Mr. and Mrs. Fasel: This is in reply to your letter of August 24, 1990, to Arthur H. Neill of this agency. You have asked for an interpretation that Federal law or regulations do not prohibit "turn signals being amber and is no way an impairment to the function of the center high mounted red stop lamp." Federal Motor Vehicle Safety Standard No. l08, Lamps, Reflective Devices, and Associated Equipment, allows the use of amber turn signals. However, since you have enclosed a drawing of a device consisting of a center highmounted stop flanked by right and left amber turn signals, your actual question appears to be whether this device is legally acceptable under Federal law. The "Abstract" you enclosed states that the stop function "is used in conjunction with the rear bumper signal lights", indicating that the intent of the device is to provide a supplementary turn signal to a vehicle's original turn signal system. Two different models are proposed: "One model for use with an already existing rear window light or without one." The device would be available through parts stores and mail order catalogues. With respect to aftermarket sales of motor vehicle equipment such as yours, there is only one Federal restriction: if the equipment is installed on a vehicle by a manufacturer, distributor, dealer, or motor vehicle repair business, it must not "render inoperative, in whole or in part", any element of design, or device, installed by the vehicle's manufacturer in accordance with a Federal motor vehicle safety standard. If a passenger car already has a center highmounted stop lamp, the model of your device that does not incorporate a center lamp (i.e., consisting only of the turn signal portion) will "straddle" it. As long as the installation of your device does not affect the performance of the existing center highmounted lamp that has been installed in accordance with Standard No. l08 (for example, such as being wired in a way that reduces the light output of the center lamp) it appears permissible. If a vehicle was manufactured before Standard No. l08 required it to have a center lamp, it does not appear that installation of the model of your device that incorporates a center highmounted stop lamp could in any way "render inoperative" any of the other rear lighting devices required by Standard No. l08. However, in either event, you should ensure that the size of the device is such that it does not interfere with the field of view requirements of Federal Motor Vehicle Safety Standard No. lll, Rearview Mirrors, in order that compliance with this standard may be maintained after installation of your device. I include a copy of Standard No. lll for your information. Finally, even if your device is acceptable under the conditions I have discussed above, it must not violate the laws of any State where it is used. We are unable to advise you on State laws, but suggest that you contact the American Association of Motor Vehicle Administrators, 4600 Wilson Boulevard, Arlington, Va. 22203. Sincerely,
Paul Jackson Rice Chief Counsel Enclosure ref:l08 d:9/25/90 |
1990 |
ID: 2671oOpen Mr. William B. Huber Dear Mr. Huber: This responds to your letter requesting an interpretation of Standard No. 101, Controls and Displays. You stated that you manufacture an electronic instrument cluster for use with van conversions and class "A" motorhomes and other vehicles. The gauges are of a bar graph type, and associated with each graph is an icon or symbol to indicate the graph function. During normal operation, the icons are illuminated to the same light intensity as the graphs. You stated that as an added feature, the icons blink when, and only when, that function becomes critical or dangerous, such as for low fuel, high temperature, low oil pressure, and low battery. You stated that some of your customers have expressed concern about using your instrument cluster because it may not comply with Standard No. 101, and you requested a formal opinion. The issues raised by your letter are addressed below. By way of background information, the National Highway Traffic Safety Administration (NHTSA) does not provide approvals of motor vehicles or motor vehicle equipment. Under the National Traffic and Motor Vehicle Safety Act (Vehicle Safety Act), it is the responsibility of the manufacturer to ensure that its vehicles or equipment comply with applicable requirements. The Vehicle Safety Act authorizes NHTSA to issue safety standards for new motor vehicles and new motor vehicle equipment. All motor vehicles and items of motor vehicle equipment manufactured or imported for sale in the United States must comply with all applicable safety standards set forth in 49 CFR Part 571. Manufacturers of motor vehicles must certify compliance of their products in accordance with Part 567, Certification. Persons altering a new vehicle prior to its first sale to a consumer are considered vehicle alterers under NHTSA's certification regulation. Part 567.7, Requirements for Persons who Alter Certified Vehicles, requires alterers to certify that the vehicle, as altered, complies with all applicable safety standards. Manufacturers, distributers, dealers, or motor vehicle repair businesses modifying a used vehicle are prohibited by section 108(a)(2)(A) of the Vehicle Safety Act from knowingly rendering inoperative any device or element of design installed on or in a motor vehicle or item of motor vehicle equipment in compliance with an applicable Federal motor vehicle safety standard. Standard No. 101 (49 CFR Part 571.101) specifies requirements for the location, identification, and illumination of motor vehicle controls and displays. The standard's requirements for displays are applicable only to vehicles with a gross vehicle weight rating of less than 10,000 pounds. See section S5. For these vehicles, the gauges identified in your letter (fuel, temperature, oil pressure, and electrical charge) are displays regulated by the standard. The primary issue raised by your letter is whether the identification of gauges may flash. As discussed below, Standard No. l0l does not prohibit such flashing. Section S5.3.3 states: S5.3.3(a) Means shall be provided for making controls, gauges, and the identification of those items visible to the driver under all driving conditions. (b) The means for providing the required visibility-- (l) Shall be adjustable, except as provided in S5.3.3(d), to provide at least two levels of brightness, one of which is barely discernible to a driver who has adopted to dark ambient roadway conditions. (2) May be operable manually or automatically, and (3) May have levels of brightness at which those items and their identification are not visible. (c) Effective September l, l989, if the level of brightness is adjusted by automatic means to a point where those items or their identification are not visible to the driver, a means shall be provided to enable the driver to restore visibility. (d) For a vehicle manufactured before September l, l989, the requirements of S5.3.3(b)(l) shall not apply to any gauge during the actuation of a telltale which shares a common light source with the gauge. Under section S5.3.3(a), means must be provided for making the identification of gauges, i.e., the icons or symbols in your design, visible to the driver under all driving conditions. The on-and-off cycling of the identification occurring during flashing would create momentary periods of time when the identification is not visible. However, it is our opinion that a flashing identification or other item is considered visible so long as it is visible during the on part of the cycle. This opinion is limited to the specific issue addressed above and does not constitute an opinion as to whether your electronic instrument cluster complies with Standard No. l0l. As you may know, several amendments were made to Standard No. l0l during l987. Enclosed for your information is a copy of the current standard. Sincerely,
Erika Z. Jones Chief Counsel Enclosure / ref:101 d:2/23/88 |
1988 |
ID: 2671yOpen Mr. James R. Mitzenberg Dear Mr. Mitzenberg: This is in reply to your letter requesting an interpretation of Federal Motor Vehicle Safety Standard No. l08. Your company offers an optional transmission retarder for supplemental braking. During initial travel of the service brake pedal, the retarder is electrically operated and the stop lamps are activated. As the service brake pedal is further depressed, air is emitted from the brake valve and the service brakes are activated. You have asked whether a noncompliance with S4.5.4 would result. This section (now renumbered S5.5.4) states that the stop lamps shall be activated upon application of the service brakes. You point out that if the stop lamps are activated by the retarder, the stop lamps could be illuminated without the service brakes actually being applied during the initial travel of the service brake pedal, and up until the point in time that air is actually emitted from the brake pedal and into the service brake system. In our opinion, there is no failure to comply by the system as you have described it. We view application of the brake pedal as evidencing an intent to slow or stop the vehicle. Thus, the operation of the stop lamp is a consequence of the application of the brake pedal. We appreciate your interest in enhancing safety with the added benefits that the retarder provides in early activation of the stop lamp. Sincerely, Paul Jackson Rice Chief Counsel /ref: 108 d:9/26/90 |
1990 |
ID: 2672oOpen Mr. Gary W. Rossow Dear Mr. Rossow: This responds to your letter requesting an interpretation of Standard No. l2l, Air Brake Systems. You asked whether a proposed design would meet the requirements of S5.l.2. Your question is responded to below. By way of background information, the National Highway Traffic Safety Administration does not provide approvals of motor vehicles or motor vehicle equipment. Under the National Traffic and Motor Vehicle Safety Act, it is the responsibility of the manufacturer to ensure that its motor vehicles or equipment comply with applicable requirements. The following represents our opinion based on the facts provided in your letter. Under section S5.l.2, trucks and buses are required to have the following equipment: "Reservoirs. One or more service reservoir systems, from which air is delivered to the brake chambers, and either an automatic condensate drain valve for each service reservoir or a supply reservoir between the service reservoir system and the source of air pressure. You stated that some of your existing air braked trucks utilize a supply reservoir or wet tank between the service reservoir system and the air compressor without using automatic condensate drain valves on the service reservoirs. You noted that the supply reservoir functions as a means of removing excess water vapor from the air supply to avoid water contamination of the braking system and works on thermodynamic principles whereby water condenses to a liquid as the hot compressed air cools. Your proposed design would utilize an air dryer between the service reservoir system and the air compressor. According to your letter, the air dryer serves the same function as the supply reservoir in your existing system but works on a different principle. You stated that the moist, compressed air passes through a filter media contained in a small canister sized reservoir. The material, a desiccant, has a high chemical affinity for water. The water absorbs on the desiccant and is later purged by stored dry air. The air dryer would have an integral automatic condensate drain valve. Since your proposed design would not include an automatic condensate drain valve for each service reservoir, the issue raised by your letter is whether it complies with S5.l.2's option for "a supply reservoir between the service reservoir system and the source of air pressure." You stated that you believe the air dryer with automatic condensate drain is the functional equivalent of the more generally accepted embodiment of a supply reservoir in the context of S5.l.2. You also noted that Standard No. l2l does not specify a separate volume for the supply reservoir, although it does require in S5.l.2.l that the combined volume of all service reservoirs and supply reservoirs be at least l2 times the total service brake chamber volume. You suggested that if the volume of the service reservoirs is l2 times the volume of the service brake chambers, it would appear that there is no requirement for a specific volume in the supply reservoir. While Standard No. l2l does not include a definition for "supply reservoir," the term is one that is commonly understood. For example, you indicated in your letter that some of your current brake system designs utilize the "more generally accepted embodiment of a supply reservoir." In considering whether a particular item of equipment can be considered a "supply reservoir," we believe that effect must be given to both "supply" and "reservoir." The dictionary defines "reservoir" as "a receptacle or chamber for holding a liquid or fluid, as oil or gas." The word "supply" is defined as "to furnish or provide." Random House Dictionary of the English Language (unabridged edition). The Society of Automotive Engineers (SAE) defines "air reservoir" as "(a) storage container for compressed air." SAE Recommended Practice J656g, "Automotive Brake Definitions and Nomenclature." Thus, in order to qualify as a "supply reservoir," an item of equipment must hold or store air in order to furnish or provide the air to the rest of the brake system. The information provided with your letter does not provide sufficient information to determine whether your air dryer qualifies as a "supply reservoir." In particular, the information does not indicate whether the air dryer holds other than a de minimis amount of air. While your letter is correct that there is no requirement for a specific volume in the supply reservoir if the volume of the service reservoirs is l2 times the volume of the service brake chambers, an air dryer with a de minimis volume could not be considered to hold or store air in order to furnish or provide the air to the rest of the brake system. On the other hand, if a supply reservoir provides an air cleaning function as well as holding or storing air in order to furnish or provide the air to the rest of the brake system, it would still be a supply reservoir. Sincerely,
Erika Z. Jones Chief Counsel ref:121 d:2/18/88 |
1988 |
ID: 2672yOpen Roger C. Fairchild, Esq. Dear Mr. Fairchild: This responds to your inquiry about Federal Motor Vehicle Safety Standards 109, 110, 119, and 120 on tires and rim selection (49 CFR 571.109, 571.110, 571.119, and 571.120), asking about the applicability of certain provisions in the Tire and Rim Association (TRA) Year Book, which those Federal safety standards incorporate by reference. As explained below, we agree that the adjustment factors in the TRA Year Book for inflation pressures and load ratings at different speeds are not applicable in determining compliance with Federal safety standards. By way of background, the National Traffic and Motor Vehicle Safety Act, ("Vehicle Safety Act," 15 USC 1381 et seq.) requires every new motor vehicle sold in the United States to be certified as complying with all applicable Federal motor vehicle safety standards. The Vehicle Safety Act specifies that the manufacturer must certify that each of its vehicles complies with all applicable safety standards in effect on the date of manufacture. Because of this statutory requirement, this agency does not approve any manufacturer's vehicles or offer assurances that the vehicles comply with the safety standards. Any person violating the Vehicle Safety Act by manufacturing or selling new noncomplying vehicles may be liable for potential penalties of $1,000 per violation up to $800,000. Section S4.3 of Standard 109 requires a new pneumatic tire for passenger cars to be labeled with certain information including one size designation, the maximum inflation pressure, and the maximum load rating. S6.5 of Standard 119 has similar marking requirements for tires on vehicles other than passenger cars. In particular, section 4.2.1(c) of Standard 109 and section 6.5(d) of Standard 119 require tires to be labeled with a maximum load rating not less than the lowest of any specified values in the manufacturer's submission or in a listed publication such as the TRA Yearbook, for tires of that size designation, type and each appropriate inflation pressure. For passenger car tires, these inflation pressures and load ratings are specified in tables in section one of the TRA Yearbook entitled, "'P' Type Tires Used on Passenger Cars and Station Wagons" and "'T' Type Spare Tires for Temporary Use on Passenger Cars and Station Wagons." For tires on vehicles other than passenger cars, these inflation pressures and load ratings are specified in the tables in section 2 of the TRA Yearbook. Question One You first asked whether the Federal safety standards incorporate an independent vehicle speed adjustment factor in determining the "vehicle normal load" and "vehicle maximum load." Your question was based on provisions in the TRA Year Book which apply such a vehicle load adjustment factor for certain tires rated for a maximum speed above 130 mph. As you are aware, S4.2 of Standard 110 provides that the vehicle maximum load on the tire shall not be greater than the applicable maximum load rating marked on the tire, and the vehicle normal load on the tire shall not be greater than the test load used in Standard 109's high speed performance test. You are correct that an adjustment factor based on the vehicle's maximum speed capacity is not required to be used in determining compliance with Standard 110 and 120. As you noted, Standard 110's requirement, as specified in S4.2.2, takes into account an adjustment for high speed use by requiring that the normal vehicle load on a tire must not exceed the test load used in Standard 109's high speed performance test in S5.5 (i.e. 88 percent of the tire's maximum load rating). Based on this provision and Standard No. 110's use of the terms "vehicle maximum load" and "maximum loaded vehicle weight," we interpret S4.2 as applying to normal vehicle uses and not special high speed applications. In fact, incorporating a load adjustment factor based on speeds of 130 to 168 mph, as the TRA provision does, would be contrary to motor vehicle safety if it encouraged vehicle operation at speeds far exceeding safe operating speeds. Therefore, the general tables in the TRA Yearbook listing maximum inflation pressures and maximum load ratings, standing alone without applying any adjustment factor, are the applicable values in determining compliance with the Federal safety standards. Question Two You also asked about a vehicle speed adjustment factor for the inflation pressure with passenger cars. As you explained, the TRA Year Book requires that the "speed category of the tire must match or exceed the theoretical maximum speed of the vehicle (i.e., actual maximum speed, as adjusted for tire inflation pressure using another factor specified by TRA). TRA sets forth two speed categories: speeds up to 210 km/h (130 mph) and speeds above 210 km/h (130 mph). As with the vehicle load adjustment factor which concerns normal vehicle applications, you are correct that an adjustment factor for inflation pressure based on the vehicle's maximum speed is not required to be used in determining compliance with Federal safety standards. Again, the general tables in the TRA Yearbook listing maximum inflation pressures and maximum load ratings, standing alone without applying any adjustment factor, are the applicable values in determining compliance with the Federal safety standards. Question Three You then asked about the applicability to the Federal standards of TRA's recommended adjustments for tire inflation pressure and "service load" for tires used on trucks and buses, depending on the maximum speed capability of the vehicle. As with the adjustment factors for passenger car tires, these adjustment factors are not relevant for compliance with Standard 119 or 120. Again, the general tables in the TRA Yearbook listing maximum inflation pressures and maximum load ratings, standing alone without applying any adjustment factor, are the applicable values in determining compliance with the Federal safety standards. I hope this information is helpful. If you have any further questions, please feel free to contact Marvin Shaw of my staff at this address or by telephone at (202) 366-2992. Sincerely,
Paul Jackson Rice Chief Counsel ref:l09#ll0#ll9#l20 d:9/26/90 |
1990 |
ID: 2673yOpen Mr. Satoshi Nishibori Dear Mr. Nishibori: This responds to your request for an interpretation of Standard No. 114, Theft Protection (49 CFR 571.114). You were uncertain whether your shift lock emergency override system, your emergency key release, and your transmission park lock system comply with S4.2 and S4.3, as amended by a May 30, 1990 final rule (55 FR 21868). On June 29, 1990, you submitted a petition for reconsideration which the agency is currently considering. Under the revised requirements, section S4.2 provides that: "Each vehicle shall have a key-locking system that, whenever the key is removed, prevents: (a) the normal activation of the vehicle's engine or motor; and (b) either steering or forward self-mobility of the vehicle or both. For a vehicle equipped with an automatic transmission with a "park" position, the key-locking system shall prevent removal of the key unless the transmission or transmission shift lever is locked in "park" or becomes locked in "park" as the direct result of removing the key." As explained below, we have made the following interpretations concerning your systems based on our understanding of them from your petition for reconsideration, your July 25, 1990 letter, and your discussions with agency staff. By way of background, the National Traffic and Motor Vehicle Safety Act, ("Vehicle Safety Act," 15 USC 1381 et seq.) requires every new motor vehicle sold in the United States to be certified as complying with all applicable Federal motor vehicle safety standards. The Vehicle Safety Act specifies that the manufacturer must certify that each of its vehicles complies with all applicable safety standards in effect on the date of manufacture. Because of this statutory requirement, this agency does not approve any manufacturer's vehicles or offer assurances that the vehicles comply with the safety standards. Any person violating the Vehicle Safety Act by manufacturing or selling new noncomplying vehicles may be liable for potential penalties of $1,000 per violation up to $800,000. Shift Lock Emergency Override You explained that your shift lock emergency override system is operable by depressing a button on the lower, rear portion of the shift lever. By depressing the button, the transmission may be shifted out of "park," independent of the ignition key position or the key being in the ignition switch. You expressed your opinion that the transmission remains "locked" in "park" until it is "unlocked," either by turning the ignition key to the "on" position and depressing the brake pedal or by operating the emergency shift release override. This led you to conclude that your emergency shift override would be permissible under S4.2(b). We disagree with your suggested interpretation. Under S4.2(b), the key-locking system must prevent removal of the key unless the transmission or transmission shift lever is locked in "park" or becomes locked in "park" as the direct result of removing the key. Given the presence of the emergency shift release override, we do not believe the transmission or transmission shift lever would ever be "locked" in park, since it could be released without regard to the key used to operate the vehicle's key-locking system. Your alternative shift lock system in which the manual override would be operable only after removing a cover over the override lever would also not appear to comply with S4.2 because the presence of a cover would not affect one's ability to release the transmission shift lever without regard to the key used to operate the vehicle's key-locking system. Emergency Key Release You explained that your emergency key release system facilitates removal of the ignition key in the event of an electrical system failure. That system permits overriding the ignition key lock, so that the ignition key can be removed from the vehicle and the driver can lock the vehicle. You explained that the emergency key release override is activated by removing a cover over the ignition switch and then using a screw driver to activate a hidden lever located inside the exposed ignition switch compartment. We do not concur with your suggested interpretation of S4.2. That requirement provides that "the key-locking system shall prevent removal of the key unless the transmission or transmission shift lever is locked in "park." The regulatory text does not refer to alternative methods of key removal such as the procedure you describe. While you state that virtually any key locking system can be overriden through some form of lock disassembly and associated procedures, we do not consider the simple override you describe to be similar to lock disassembly. Therefore, an emergency key release system in which the key could be removed in a position other than "park" would not comply with S4.2, regardless how the key could be removed. Nevertheless, such an emergency key release would be permissible if it were operable only while the transmission or transmission shift lever were locked in the "park" position. You should be aware that we are evaluating such systems in our review of the petitions for reconsideration to the final rule. Park Lock System You explained that your park lock system prevents drivers from inadvertently depressing the accelerator pedal rather than the brake pedal when shifting out of "park". This is accomplished by permitting the transmission lever to be moved out of "park" only if the ignition key is in the "on" position and the brake pedal is depressed. You further explained that if the transmission is placed in "park," the shift lever locks in that position when the ignition key is turned to the "off" position. You expressed your belief that your park lock system complies with S4.3, as amended. I agree that your park lock system appears to comply with S4.3. That provision requires that the prime means for deactivating the vehicle's engine or motor, typically the ignition key, shall not activate the key-locking system described in S4.2(b). Based on our understanding of your key-locking system, it appears to comply with S4.3 because that provision refers to the key-locking system and not a transmission shift lock. As you correctly note, the purpose of S4.3 is to prevent the potentially dangerous situation in which the ignition key of a moving vehicle is turned to the "off" position causing the steering column to lock. You asked that we continue to consider your petition for reconsideration, if, as we have done, we concluded that some of your suggested interpretations were incorrect. We will notify you of our response to that petition as soon as we complete our review of it. I hope this explanation is helpful. Please contact Mr. Marvin Shaw of my staff at (202) 366-2992 if you have any further questions. Sincerely,
Paul Jackson Rice Chief Counsel Enclosure ref:ll4 d:9/26/90 |
1990 |
ID: 2674yOpen Mr. Robert Roden Dear Mr. Roden: This responds to your questions about the requirements for key-locking systems in section S4.2(b) of Federal Motor Vehicle Safety Standard No. 114, Theft Protection (49 CFR 571.114). As explained below, the enclosed copy of the agency's recent final rule amending this provision may be relevant to your inquiry (55 FR 21868, May 30, 1990). By way of background, the National Traffic and Motor Vehicle Safety Act, ("Vehicle Safety Act," 15 USC 1381 et seq.) requires every new motor vehicle sold in the United States to be certified as complying with all applicable Federal motor vehicle safety standards. The Vehicle Safety Act specifies that the manufacturer must certify that each of its vehicles complies with all applicable safety standards in effect on the date of manufacture. Any person violating the Vehicle Safety Act by manufacturing or selling new noncomplying vehicles may be liable for potential penalties of $1,000 per violation up to $800,000 for a related series of violations. One such Federal safety standard is Standard No. 114, Theft Protection, which applies to passenger cars, and to trucks and multipurpose passenger vehicles having a gross vehicle weight rating of 10,000 pounds or less. Your first question asked whether section S4.2(b) requires key locking systems to prevent removal of the ignition key except when the transmission is in the "park" position. Section S4.2(b) currently requires such vehicles to have a "key-locking system that, whenever the key is removed, will prevent...(b) either steering or forward self-mobility of the vehicle, or both." However, the agency has recently amended section S4.2(b) to read as follows: Each vehicle shall have a key-locking system that, whenever the key is removed, prevents: (a) the normal activation of the vehicle's engine or motor; and (b) either steering or forward self-mobility of the vehicle or both. For a vehicle equipped with an automatic transmission with a "park" position, the key-locking system shall prevent removal of the key unless the transmission or transmission shift lever is locked in "park" or becomes locked in "park" as the direct result of removing the key. You should be aware that this amendment takes effect on September 1, 1992. For vehicles manufactured before September 1, 1992, S4.2(b) merely requires that when the key is removed, the key-locking system must prevent steering or forward self-mobility, or both. This provision does not address the issue of the transmission's position at the time of key removal. In contrast, under the recent amendment applicable to vehicles manufactured on or after September 1, 1992, S4.2(b) requires automatic transmission vehicles to prevent removal of the key unless the transmission or transmission shift lever is locked in "park" or becomes locked in "park" as the direct result of removing the key. Your second question asked whether a replacement key-locking system is required to comply with Standard No. 114. Because Standard No. 114 applies to new motor vehicles and not to motor vehicle equipment, the standard does not in itself require aftermarket replacement systems to comply with its requirements. However, you should be aware that section 108(a)(2)(A) of the Vehicle Safety Act prohibits manufacturers, distributors, dealers, or motor vehicle repair businesses from knowingly "rendering inoperative," in whole or in part, any device or element of design installed on or in a vehicle to comply with an applicable safety standard. Your third question asked how long the key locking system is required to perform under S4.2(b) of the standard. The Vehicle Safety Act only requires manufacturers to assure that vehicles and equipment comply with applicable safety standards at the time of the first consumer purchase. However, please note that if at any time a manufacturer or the agency determines that a vehicle or item of equipment contains a safety-related defect, which could result from the failure of a system to operate properly, the manufacturer is required to notify all product purchasers of the defect and remedy the defect without charge. See 15 U.S.C. 1411-1414. I hope this information is helpful. If you have any further questions, please feel free to contact Marvin Shaw of my staff at this address or by telephone at (202) 366-2992. Sincerely,
Paul Jackson Rice Chief Counsel Enclosures ref:VSA#ll4 d:9/l9/90 |
1970 |
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.