ID: 20822.ztv

Mr. Timothy J. Flanagan
Manager, Gas Methods & Training
PECO Energy Company
300 Front Street
West Conshohocken, PA 19428-2723

Dear Mr. Flanagan:

This is in reply to your letter of October 6, 1999, requesting permission "to install additional lighting for visibility and safety purposes" on PECO Energy Company emergency service vehicles.

You report that your vehicles currently are equipped with an "amber strobe light on the roof and the regular hazard lights." You would like to add "additional strobe lights in the rear and front" of your vehicles to be used while the vehicles are stationary, and state that this additional lighting "will not interfere with any other warning or safety devices on the vehicle such as headlights or turn signals."

Strobe lamps are not permitted as original equipment on motor vehicles. This is because all lamps with which a vehicle is supplied must be steady burning, except for turn signals and hazard warning signals, and headlamps which may be automatically flashed for signaling purposes (see S5.5.10 of Federal Motor Vehicle Safety Standard (FMVSS) No. 108, Lamps, Reflective Devices, and Associated Equipment). We regard a strobe lamp as one that flashes, and hence prohibited as original equipment.

As for vehicles in the field, such as yours, Federal law (49 U.S.C. 30122) prohibits manufacturers, dealers, distributors, and motor vehicle repair businesses from making inoperative safety equipment installed in accordance with FMVSS No. 108 (and any other applicable FMVSS as well). Installation of a strobe lamp would create a noncompliance with FMVSS No. 108 which we equate with "making inoperative" within the meaning of the statute. However, the list of persons prohibited from making safety modifications affecting compliance do not include vehicle owners. Thus, if PECO Energy has its own vehicle repair facilities, your company may install the strobe lamps without violating Federal law. Use of these lamps is subject to the laws of Pennsylvania.

If you have any questions, you may call Taylor Vinson of this Office (202-366-5263).

Sincerely,
Frank Seales, Jr.
Chief Counsel
ref.108
d:1/7/00

ID: 2973yy

Mr. Paul R. Kirchgraber
Souvenirs of the Future
Suite 201-71
3435 Ocean Park Blvd.
Santa Monica, CA 90405

Dear Mr. Kirchgraber:

This is in reply to your letter of April 16, 1991, with respect to which Federal motor vehicle safety standards, if any, must be met in order to sell an exterior tire/wheel cover with reflective characteristics that will help to make "the vehicle more visible to the surrounding traffic." In addition, you "want to be certain that the reflective nature of the fabric used in this cover does not present a safety hazard", and ask for the citation to "appropriate federal test standards from the code of federal regulations for similar automotive accessories."

There are no Federal motor vehicle safety standards that establish performance requirements for reflective material of this nature, or for wheel coverings on exterior-mounted tires. The standard on vehicle lighting, Motor Vehicle Safety Standard No. l08, does prohibit, as original equipment, the installation of a "reflective device or other motor vehicle equipment" that impairs the effectiveness of lighting equipment required by the standard. It is theoretically possible that your material could create glare in the eyes of a following operator so that (s)he would fail to respond to a stop signal, or a turn signal. The samples submitted with your letter are too small for us to judge its reflectivity, and we suggest that you conduct your own tests, approaching a vehicle with the tire cover from the rear, with headlamps on the lower beam. This, to us, is preferable to your redesigning the material to conform to any federal test standard relating to reflectivity.

Although the color of lighting equipment on the rear is generally red, with amber permitted for turn signals, and white required for back up lamps, we do not believe that the use of additional colors would create any confusion. In short, we believe that the wheel cover will be perceived for the wheel cover it is.

I hope that this responds to your concerns.

Sincerely,

Paul Jackson Rice Chief Counsel

ref:l08 d:5/6/9l

ID: nht91-3.38

DATE: May 6, 1991

FROM: Paul Jackson Rice -- Chief Counsel, NHTSA

TO: Paul R. Kirchgraber -- Souvenirs of the Future

TITLE: None

ATTACHMT: Attached to letter dated 4-16-91 from Paul R. Kirchgraber to Paul Jackson Rice (OCC 5964)

TEXT:

This is in reply to your letter of April 16, 1991, with respect to which Federal motor vehicle safety standards, if any, must be met in order to sell an exterior tire/wheel cover with reflective characteristics that will help to make "the vehicle more visible to the surrounding traffic." In addition, you "want to be certain that the reflective nature of the fabric used in this cover does not present a safety hazard", and ask for the citation to "appropriate federal test standards from the code of federal regulations for similar automotive accessories."

There are no Federal motor vehicle safety standards that establish performance requirements for reflective material of this nature, or for wheel coverings on exterior-mounted tires. The standard on vehicle lighting, Motor Vehicle Safety Standard No. 108, does prohibit, as original equipment, the installation of a "reflective device or other motor vehicle equipment" that impairs the effectiveness of lighting equipment required by the standard. It is theoretically possible that your material could create glare in the eyes of a following operator so that (s)he would fail to respond to a stop signal, or a turn signal. The samples submitted with your letter are too small for us to judge its reflectivity, and we suggest that you conduct your own tests, approaching a vehicle with the tire cover from the rear, with headlamps on the lower beam. This, to us, is preferable to your redesigning the material to conform to any federal test standard relating to reflectivity.

Although the color of lighting equipment on the rear is generally red, with amber permitted for turn signals, and white required for back up lamps, we do not believe that the use of additional colors would create any confusion. In short, we believe that the wheel cover will be perceived for the wheel cover it is.

I hope that this responds to your concerns.

ID: nht90-4.30

TYPE: Interpretation-NHTSA

DATE: October 2, 1990

FROM: Paul Jackson Rice -- Chief Counsel, NHTSA

TO: S. Kadoya -- Manager, Safety and Technology, Mazda Research and Development of North America, Inc.

TITLE: None

ATTACHMT: Attached to letter dated 11-7-89 from S. Kadoya to S.P. Wood

TEXT:

This responds to your request for interpretations of several safety standards and the Bumper Standard, in connection with a planned "active" suspension system. I regret the delay in responding to your letter. Your questions are responded to 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 statutes administered by this agency, it is the responsibility of the manufac turer to ensure that its vehicles and equipment comply with applicable standards. The following represents our opinion based on the facts provided in your letter.

According to your letter, Mazda is concerned about the protocol of compliance testing of vehicles equipped with an active suspension system. This concern arises because many standards do not specify a suspension height that is to be used during complianc e testing. As you noted, this has not been a concern for conventional suspension systems, since they do not provide for variable height.

Mazda's planned active suspension system would be actuated by hydraulic fluid or compressed air, with control pressure being developed by a hydraulic pump or air compressor driven off the engine. Consequently, the active suspension system would be opera tional only when the vehicle's engine is operating. At vehicle speeds in excess of "z" mph, where z is greater than 35 mph, the suspension height would be lowered by "x" mm from the nominal or design position for vehicle operation. If the engine/vehicl e were not used for several consecutive days, pressure in the control system would fall such that the supension height may be lowered from the nominal or design position for vehicle operation by "y" mm, where y is greater than x. The suspension height w ould return to the nominal or design position for vehicle operation after such an extended period of inoperation almost immediately after starting the vehicle's engine.

Before discussing your specific questions, I would like to discuss more generally the issue of how compliance is determined in situations where a standard does not specify a particular test condition. In issuing Federal motor vehicle safety standards, N HTSA attempts to specify all relevant test conditions. The agency does this as part of ensuring that its standards are objective and practicable. As a practical matter, however, it is not possible to specify every conceivable test condition. This is p articularly true for ones which may only be relevant to

as-yet-undeveloped technologies.

In cases where a standard does not specify a particular test condition, we believe there are several relevant factors to consider in interpreting the standard. First, in the absence of specification of a particular test condition, we believe there is a presumption that the requirements need to be met regardless of such test condition, since the standard does not include any language which specifically limits applicability of its requirements to such test condition. For example, where a standard does n ot specify suspension height, its requirements may need to be met at all heights to which the suspension can be adjusted. Before reaching such a conclusion, however, we also consider the language of the standard as a whole and its purposes. Even if a s tandard is silent as to a particular test condition, the language of the standard or its purposes may indicate limitations on such test condition. Finally, in situations where a limitation on a particular test condition may appear to be appropriate, we also must consider whether the limitation is sufficiently clear, both with respect to justification and specificity, to be appropriate for interpretation. For example, in a situation where it may appear to be reasonable to limit a particular test condit ion but it is not obvious what particular limitation should be adopted, it would be inappropriate to select a particular limitation by interpretation. Instead, such a decision should be reached in rulemaking.

I will now address the specific questions asked in your letter.

Standard No. 108, Lamps, Reflective Devices, and Associated Equipment

In asking about Standard No. 108, you stated the following:

NHTSA has previously issued an interpretation of the requirements of FMVSS No. 108; at the request of a confidential applicant and dated February 12, 1985, with respect to active suspension equipped vehicles. This interpretation stated that the requirem ents of FMVSS 108 must be meet (sic),"...at any time in which..." lamps, reflective devices, and associated equipment are to be,"...operated for its intended purpose." Consequently, headlamps, tailamps, stoplamps, the license plate lamp, and side marker lamps, must comply with the location requirements of FMVSS No. 108 whenever the vehicle's ignition is in the "on" postiion. Conversely, reflex reflectors, and turn signal lamps that also function as hazard warning signal flashers must comply with the lo cation requirements when the vehicle's ignition is in either the "on" or "off" position. However, it is Mazda's interpretation that hazard warning flashers are not intended to be operational for a period of days, but rather for a period of hours, at max imum, only.

You then asked two questions, (1) whether Mazda's understanding of the subject NHTSA interpretation is accurate, and (2) whether Mazda's interpretation of the maximum intended operating duration of hazard warning signal flashers is correct.

I note that the February 1985 interpretation was written in the context of a vehicle with a variable height system actuated by hydraulic fluid. In that particular system, the hydraulic pressure relaxed over a period of

about three hours after the ignition was turned off, with the result that the vehicle assumed a lower height than it would have during driving. NHTSA stated the following:

We believe that the minimum height requirement should be met for any lamp at any time in which it is operated for its intended purpose. Since vehicles at rest do not require use of headlamps, the minimum height requirement would be measured at the point after the ignition is on and when the car begins to travel (your letter implies that the time lag between turning on the ignition and restoration of a complying mounting height is a matter of seconds). On the other hand, the hazard warning signal lamps are frequently operated when the vehicle is stopped, and therefore the minimum mounting height of turn signal lamps, through which they operate, must be met with the ignition off, even if the system requires three hours to deplete itself and lower the v ehicle to its minimum height.

With respect to your question of whether Mazda's understanding of the interpretation is correct, I would like to note two points. First, while you state that "the requirements of FMVSS 108" must be met at any time in which lamps, reflective devices, and associated equipment are to be operated for their intended purpose, our interpretation was limited to standard's minimum height requirement. While we are prepared, if asked, to address other requirements, our interpretations should be understood to be limited to their specific facts and conclusions. Second, while our interpretation only addressed headlamps and hazard warning signal lamps, you applied the interpretation for headlamps to taillamps, stoplamps, the license plate lamp, and side marker lam ps, and the interpretation for hazard warning signal lamps to reflex reflectors. We concur with this application, with respect to Standard No. 108's minimum height requirement.

We do not agree with Mazda's suggested interpretation of the maximum intended operating duration of hazard warning signal flashers. You would apparently like us to conclude that Standard No. 108's minimum height requirement for hazard warning signal fla shers does not apply after a vehicle's ignition has been turned off for a matter of days.

In addressing how Standard No. 108 applies in the absence of a specification for vehicle height, our February 1985 interpretation differentiates between situations where the vehicle is operating and where it is not. Looking at the purpose of the require ments in question, we believe it is obvious that the minimum height requirement for headlamps is only relevant in situations where the vehicle is operating, while the minimum height for hazard warning signal lamps is also relevant to situations where the vehicle is stopped and the ignition turned off. However, we believe that any determination that Standard No. 108's minimum height requirement for hazard warning signal flashers should not apply after a specified number of hours after the ignition has be en turned off is one that would need to be addressed in rulemaking.

It is therefore my opinion that the minimum mounting height of hazard warning signal lamps must be met at all heights with the ignition off, even if the system requires days to deplete itself and lower the vehicle

to its minimum height. If you believe that a time limitation should be placed on this requirement, I note that you can submit a petition for rulemaking requesting such a change.

Standard No. 111, Rearview Mirrors

You requested an interpretation of section S5.1.1 of Standard No. 111, which generally requires a passenger car's rearview mirror to "provide a field of view with an included horizontal angle measured from the projected eye point of at least 20 degrees, and sufficient angle to provide a view of level road surface extending to the horizon beginning at a point not greater than 200 feet to the rear of the vehicle...." You noted that since the specified procedures for determining the location of the driver 's eye reference points are made referenced to points with the vehicle's cabin, your active suspension system would not affect these measurements. However, different vehicle heights would be relevant to whether there is a view of level road surface exte nding to the horizon beginning at a point not greater than 200 feet to the rear of the vehicle. You stated that, based on "intended purpose," Mazda's interpretation of Standard No. 111 is that the requirements of this standard are to be met when the vehi cle's ignition is in the "on" position as rearview mirrors are not intended to be used when the vehicle's engine is not operating.

You then asked two questions, (1) whether Mazda's interpretation of the requirements of FMVSS No. 111 with respect to the state of the vehicle's ignition switch is correct, and (2) for the purposes of compliance testing to the requirements of FMVSS No. 1 11, what means of maintaining the intended suspension height for a given speed and operating condition would be satisfactory to NHTSA.

We agree that the field of view requirement specified in S5.1.1 for rearview mirrors need not be met for vehicle heights that only occur when the engine is not on, since the requirement is only relevant in situations where the vehicle is operating. Howe ver, the requirement would need to be at all vehicle heights that occur during vehicle operation, under the loading conditions specified in S5.1.1.

With respect to the issue of how suspension height should be maintained for purposes of compliance testing, you note early in your letter that, for reasons of practicality and safety, a vehicle's engine is not actually operational during compliance testi ng. However, since the active suspension system derives its power from the vehicle's engine, the system's ability to maintain and regulate suspension height is only possible during engine operation. You therefore indicated that Mazda is seeking guideli nes (for several standards) by which Mazda may be able to establish a means to maintain the intended suspension height for compliance testing purposes in the absence of engine operation.

We are not able, in an interpretation, to specify a particular means for maintaining suspension height for compliance testing in the absence of engine operation. However, the basic principle that should be followed in selecting a means for maintaining s uspension height is that it should not result in different test results than would occur if testing could be conducted with suspension height being maintained by engine operation,

i.e., what would happen in the real world. This should be relatively straightforward for section S5.1.1 of Standard No. 111, since the test is static. For a crash test, it is important that a vehicle not be altered in any way that would change the vehi cle's crash performance relevant to the aspect of performance being tested.

Standard No. 204, Steering Control Rearward Displacement

In asking about Standard No. 204, you stated the following:

Section S4 of this standard specifies the compliance parameter for this standard. Section S5 specifies the testing conditions to determine compliance with this standard. Section S5.1 specifies that the vehicle be loaded to its unloaded vehicle weight. Section S5.5 specifies that the vehicles fuel tank be filled with Stoddard solvent to any capacity between 90 and 95 percent of the total capacity of the tank. Mazda's interpretation of the requirements of this standard is that they are to be met when the vehicle's ignition switch is in the "on" position only. Furthermore, Mazda interprets the vehicles suspension height pursuant to S5.1 and S5.5 to be the intended suspension height for the vehicle given the conditions of S4, i.e., 30 mph vehicle speed and steered wheels are positioned straight ahead.

You then asked whether Mazda's interpretation of the requirements of FMVSS No. 204 are correct. As discussed below, we agree that Standard No. 204's requirements need to be met only at the suspension height that occurs at a 30 mph vehicle speed and with steered wheels positioned straight ahead.

Standard No. 204 specifies requirements limiting the rearward displacement of the steering control into the passenger compartment to reduce the likelihood of chest, neck, or head injury. These requirements must be met in a 30 mile per hour perpendicular impact into a fixed collision barrier. While the standard specifies a number of test conditions, it does not specify suspension height.

Looking at the Standard No. 204 as a whole, we believe it is clear that NHTSA explicitly decided to limit the standard's evaluation of steering control rearward displacement to how vehicles perform in 30 mph perpendicular impacts, even though the require ments have relevance at lower and higher speeds. Therefore, we agree that the standard's requirements need to be met only at suspension heights that occur at a 30 mph vehicle speed and with steered wheels positioned straight ahead.

With respect to Mazda's question concerning means of maintaining intended suspension height for compliance testing, please see our discussion provided with respect to Standard No. 111.

Standard No. 208, Occupant Crash Protection

In asking about Standard No. 208, you stated the following:

Section S8.1.1(d), "Vehicle test attitude," specifies the procedure for determining the vehicle test attitude that is to be used for testing. Specifically, this section requires that the vehicle's pretest attitude,

"...shall be equal to either the as delivered or fully loaded attitude or between the as delivered and fully loaded attitude." The as delivered attitude is defined by S8.1.1(d) as being, "...the distance between a level surface and a standard reference point on the test vehicle's body, directly above each wheel opening, when the vehicle is in its "as delivered" condition. The "as delivered" condition is the vehicle as received at the test site..." Because it is highly likely that the test vehicle wil l not have been operated for a period of days prior to arriving at the test site, the suspension height may have fallen by "y" mm. The fully loaded attitude is defined as the attitude of the vehicle when loaded in accordance with S8.1.1(a) or (b) and a determination of the height of the suspension at the fully loaded condition is made from the same level surface, using the same standard reference points, as were used to determine the "as delivered" condition. The definition of the "as delivered" condi tion is quite clear. However, Mazda interprets the "fully loaded condition" of the vehicle to be the condition when the vehicle's ignition is "on." In this instance it is likely that the height of the standard reference points on the vehicles body when in the "fully loaded condition" relative to the level surface will be greater than for the "as delivered" condition. Conversely, conventional vehicle suspension systems will likely have an "as delivered" height greater than the "full loaded" height. H owever, this fact is of no importance as S8.1.1(d) states that the pretest vehicle attitude may be, "...between the as delivered and the fully loaded attitude." With respect to the injury criteria specified by section S6 of this standard, Mazda's interp retation is that these criteria must be met with the vehicle's ignition in the "on" position only.

You then asked three questions, (1) whether Mazda's interpretation of the definition of the "fully loaded condition" is correct with respect to the condition of the ignition switch, (2) whether Mazda's interpretation of the irrelevance of the relative re lationship between the "as delivered" and "fully loaded" conditions is correct, and (3) whether Mazda's interpretation of the meaning of "between the as delivered and the fully loaded attitude" is correct.

In addressing your questions, I will begin by noting that Standard No. 208 specifies occupant protection requirements which must be met in specified crash tests at any impact speed up to and including 30 mph. While the standard specifies a number of tes t conditions, it does not specify suspension height. However, the standard does specify vehicle attitude, which is closely related to suspension height. In addressing how Standard No. 208 applies in the absence of a specification for vehicle height, th e relationship between the standard's attitude specification and vehicle height must be considered.

Section S8.1.1(d) specifies the attitude of the vehicle during testing, i.e., the angle of the vehicle relative to the ground. This test condition ensures that the vehicle is not overly tilted toward the front or back, or to one side. The section accom plishes this purpose by specifying that, during a compliance test, the height of the vehicle at each wheel is within a specified range. This range, which may be somewhat different for each wheel, is determined by looking at the vehicle in the "as delive red" condition and the "fully loaded" condition. A vehicle must meet the requirements of Standard No. 208 when its height at each wheel is

anywhere within the specified ranges.

On first glance, one might read section S8.1.1(d) to create a height requirement, since ranges of height are determined under that section (at each wheel). This would be incorrect, except in a very narrow sense, since Standard No. 208 does not specify, for vehicles with variable height suspension systems, what suspension height should be used in the two conditions ("as delivered" and "fully loaded") where the specified ranges of height are determined under section S8.1.1(d).

Looking at the Standard No. 208 as a whole, we believe it is clear that NHTSA explicitly decided to limit the standard's evaluation of occupant crash protection in frontal impacts to how vehicles perform in impacts of 30 mph or less, even though the requ irements also have relevance at higher speeds. It is our interpretation that the frontal crash test requirements need to be met at all suspension heights that can occur at speeds of 30 mph or less, with the vehicle operational. It is also our interpret ation that the crash test requirements need to be met only at suspension heights that can occur at the speed used in the crash test.

A remaining issue is how section S8.1.1(d) applies for vehicles with variable height suspension systems. As discussed below, vehicle attitude should be determined under this section using the actual suspension setting (or equivalent, if the setting is a utomatic) to be used in a crash test.

For purposes of illustration, I will assume a vehicle with two very different suspension height settings. It would not be appropriate to conclude that the ranges of height determined under section S8.1.1(d) should simultaneously cover both suspension he ights. Such ranges would be very large, and would not ensure that the vehicle is not overly tilted toward the front or back, or to one side. Moreover, such ranges would not be relevant to the real world, with respect to vehicle attitude.

Traditional vehicles can be viewed as having a single suspension "setting." This single suspension condition is used in determining vehicle attitude under section S5.8.8.1. The ranges of height result from the differences in loading under the "as deliv ered" and "fully loaded" conditions.

A single suspension "setting" (or equivalent, if the setting is automatic) should similarly be used in determining vehicle attitude for vehicles with variable height suspension systems. The "setting" should be the one to be used in a crash test.

With respect to Mazda's question concerning means of maintaining intended suspension height for compliance testing, please see our discussion provided with respect to Standard No. 111.

You also asked for an interpretation of section S8.2.7 of Standard No. 208. That section specifies additional conditions to be used for lateral moving barrier crash testing. Section S8.2.7(a) states that the vehicle is at rest in its "normal attitude." You stated that Mazda interprets the meaning of "normal attitude" to be that vehicle attitude which is intended

when the vehicle's ignition is in the "on" condition, with the vehicle loaded pursuant to S8.1.1(a) or (b), and while the vehicle is at rest. Standard No. 208 provides manufacturers the option of either equipping their vehicles with safety belts or meeti ng certain alternative requirements, including lateral moving barrier crash test requirements. These requirements are relevant at all vehicle heights that can occur during vehicle operation, regardless of speed. Moreover, NHTSA has not decided to limit the standard's evaluation of this aspect of safety performance to how vehicles perform at certain limited speeds. It is our interpretation that the lateral moving barrier crash test requirements, if applicable, must be met at all suspension heights that can occur with the vehicle operational. "Normal attitude" is the attitude determined under section S8.1.1(d). As discussed above, attitude for vehicles equipped with variable height suspension systems is determined under section S8.1.1(d) using the ac tual suspension setting (or equivalent, if the setting is automatic) to be used in a crash test.

Standards No. 212, Windshield Mounting; No. 219, Windshield Zone Intrusion; No. 301, Fuel System Integrity

In asking about Standards No. 212, No. 219, and No. 301, you noted that NHTSA has previously issued an interpretation to Mazda about how these standards apply to adjustable height suspension systems. In a letter dated August 10, 1982, the agency address ed a vehicle equipped with a suspension system having two height positions, one for normal highway driving and another for off-road driving, which could be selected by the driver. NHTSA stated the following:

(Safety Standards No. 212, No. 219, and No. 301) do not specify a height adjustment because almost all vehicles have a single, set adjustment. . . After careful consideration, it is the agency's position that such a vehicle capable of variable height adj ustment would have to comply with the vehicle adjusted to any position that is possible. This is true because the vehicle could be driven on the highway, for example, even if it were adjusted to the off-road position. Consequently, it is important that the vehicle comply with the standards in all positions.

You noted that while suspension height could be adjusted by the driver for the system discussed in the agency's previous interpretation, the active suspension system you are currently considering would use an on-board electronic controller to select susp ension height, and suspension height would not be adjustable by the driver. Consequently, according to your letter, only one unique set of suspension height parameters is possible for a given vehicle speed and loading condition as is the case with conve ntional suspension systems. You stated that because it is possible to determine exactly what the intended suspension height should be for a given situation, it is Mazda's opinion that the test vehicle should be tested at the intended suspension height g iven the specified speed and loading conditions. You also stated that, using an "intended purpose" argument, Mazda concludes that the requirements of the three standards are to be met only when the vehicle's ignition is "on." You then asked whether thes e suggested interpretations are correct.

Standard No. 212 specifies windshield retention requirements that must be

met in a specified frontal crash test at any impact speed up to and including 30 mph. Similarly, Standard No. 219 specifies windshield zone intrusion requirements that must be met in a specified frontal crash test at any impact speed up to and including 30 mph. Standard No. 301 specifies fuel system integrity requirements for several specified crash tests. These include a frontal crash test similar to those in Standards No. 212 and No. 219. Requirements for this test must be met at any impact speed up to and including 30 mph. Other tests include a rear moving barrier crash test, a lateral moving barrier crash test, and a static rollover test.

We agree that the requirements of Standards No. 212, No. 219, and No. 301 need not be met for vehicle heights that only occur when the engine is not on, since the requirements are only relevant in situations where the vehicle is operating. Looking at th e three standards as a whole, we believe it is clear that, for the frontal tests specified by the three standards, NHTSA decided to limit the standards' evaluation of safety performance to how vehicles perform in impacts of 30 mph or less, even though th e requirements have relevance at higher speeds. It is our interpretation that the frontal crash test requirements specified by these standards need to be met at all suspension heights that can occur at speeds of 30 mph or less, with the vehicle operatio nal. It is also our interpretation that the crash test requirements need to be met only at suspension heights that can occur at the speed used in the crash test.

We reach a different conclusion for Standard No. 301's other crash test requirements. These requirements are relevant at all vehicle speeds and suspension heights. Moreover, NHTSA has not decided to limit the standard's evaluation of these aspects of s afety performance to how vehicles perform at certain limited speeds. It is our interpretation that these crash test requirements must be met at all suspension heights that can occur with the vehicle operational.

Part 581 Bumper Standard

In asking about the Part 581 Bumper Standard, you noted that NHTSA has previously issued several interpretations of how the standard applies to vehicles with adjustable height suspension systems. In a letter to Subaru dated May 6, 1986, NHTSA stated the following:

Given the absence of a specific test condition concerning suspension height, it is our interpretation that a vehicle must be capable of meeting the standard's damage criteria at any height position to which the suspension can be adjusted. There is no la nguage in the test requirements of the standard limiting their applicability to "the manufacturer's nominal design highway adjusted height position."

This interpretation is consistent with the purpose of the Bumper Standard, set forth in section 581.2, to reduce physical damage to the front and rear ends of a passenger motor vehicle from low speed collisions. If a vehicle's suspension could be adjust ed so that its bumper height resulted in bumper mismatch with other vehicles in the event of low speed collisions, the reduction in physical damage attributable to the Bumper Standard would be defeated in whole or part.

In another letter, dated February 12, 1985, NHTSA stated that a vehicle is "required to meet the pendulum test of Part 581 in any vehicle use scenario in which the vehicle operates, and the barrier test of Part 581 when the engine is idling."

You suggested, for the barrier test, that the agency's May 1986 interpretation may be inappropriate for your active suspension system, since your system provides for only one suspension height when the engine is idling. You also suggested, for the pendu lum test, that these interpretations seem to be in conflict with the Bumper Standard's stated purpose to reduce physical damage to motor vehicles in low speed collisions. We assume that you are referring to the fact that your suspension system has heigh ts that occur only at speeds greater than 35 mph. You then requested that NHTSA provide an interpretation of Part 581 with respect to your system.

In addressing how Part 581 applies to vehicles equipped with an active suspension system, I will address separately the standard's barrier and pendulum tests. For the barrier test, a vehicle must meet specified damage criteria after an impact into a fix ed barrier that is perpendicular to the line of travel of the vehicle, at 2.5 mph. Section 581.6 sets forth conditions applicable to bumper testing. Under section 581.6(c), at the onset of a barrier impact, the vehicle's engine is operating at idling s peed.

Looking at the Bumper Standard as a whole, we believe it is clear that NHTSA decided to limit the barrier test's evaluation of bumper performance to how vehicles perform in 2.5 mph frontal impacts, even though the requirements have relevance at lower and higher speeds and when the vehicle is nonoperational. It is our interpretation that the barrier test requirements specified by this standard need to be met at all suspension heights that can occur at 2.5 mph.

We reach a different conclusion for the pendulum test, which serves the purpose of creating a bumper height requirement. This requirement is relevant at all vehicle speeds and suspension heights, and when the vehicle is nonoperational. I note that whil e Mazda is correct that the Bumper Standard's stated purpose is to reduce physical damage to motor vehicles in low speed collisions, NHTSA has justified the bumper height requirement on safety concerns related to "higher speed collisions." In proposing Standard No. 215, the predecessor of Part 581, the agency stated:

. . . in higher speed collisions the tendency of a bumper to override another or to ride under or over a guardrail creates hazards for vehicle occupants. Vehicles with interlocking bumpers block traffic and expose their occupants to considerable danger, particularly if they attempt to get out to unlock bumpers. By overriding or underriding a guardrail, a bumper may strike a supporting post, or similar fixed object, with serious consequences for the vehicle and its occupants. 35 FR 17999, November 24, 1970.

The relevance of the bumper height requirement to nonoperational

situations is also clear, e.g., to help protect parked cars.

Moreover, NHTSA has not decided to limit the bumper height requirement to how vehicles perform at certain limited speeds. It is our interpretation that the pendulum test requirements must be met at all suspension heights that can occur, regardless of ve hicle speed or whether the ignition is turned on.

This interpretation is consistent with an October 18, 1978 letter to Nissan, in which NHTSA addressed how the pendulum test applies to vehicles equipped with height control systems, including automatic height control systems. Among other things, the age ncy stated the following:

. . . There is no language in the pendulum test requirements of the standard which would limit their applicability to only the ignition-on or ignition-off situation or to the recommended driving position for normal roadways. The vehicle must be capable of meeting the pendulum test requirements at all stable bumper heights possible at unloaded vehicle weight.

Thus, in the situations described in Question 1 and 2 of your letter, in which an automatic height control system is employed, the vehicle must comply with the pendulum test requirements in both the ignition-on and ignition-off positions . . . .

I note that one of our past letters, a December 24, 1984 letter addressed to Porsche, appears to suggest that the pendulum test must be met in any setting in which the system operates "when the engine is idling." This might be read to suggest that the p endulum test need not be met when the vehicle is nonoperational. However, this interpretation cited section 581.6(c) in concluding that the engine is idling during Part 581 testing. Section 581.6(c) applies only to the barrier test and not the pendulum test. We therefore consider this interpretation to be incorrect to the extent that it is inconsistent with the analysis presented above.

ID: 2705y

Mr. S. Kadoya
Manager
Safety and Technology
Mazda Research and Development
of North America, Inc.
l203 Woodbridge Avenue
Ann Arbor, Michigan 48l05

Dear Mr. Kadoya:

This responds to your request for interpretations of several safety standards and the Bumper Standard, in connection with a planned "active" suspension system. I regret the delay in responding to your letter. Your questions are responded to 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 statutes administered by this agency, it is the responsibility of the manufacturer to ensure that its vehicles and equipment comply with applicable standards. The following represents our opinion based on the facts provided in your letter.

According to your letter, Mazda is concerned about the protocol of compliance testing of vehicles equipped with an active suspension system. This concern arises because many standards do not specify a suspension height that is to be used during compliance testing. As you noted, this has not been a concern for conventional suspension systems, since they do not provide for variable height.

Mazda's planned active suspension system would be actuated by hydraulic fluid or compressed air, with control pressure being developed by a hydraulic pump or air compressor driven off the engine. Consequently, the active suspension system would be operational only when the vehicle's engine is operating. At vehicle speeds in excess of "z" mph, where z is greater than 35 mph, the suspension height would be lowered by "x" mm from the nominal or design position for vehicle operation. If the engine/vehicle were not used for several consecutive days, pressure in the control system would fall such that the supension height may be lowered from the nominal or design position for vehicle operation by "y" mm, where y is greater than x. The suspension height would return to the nominal or design position for vehicle operation after such an extended period of inoperation almost immediately after starting the vehicle's engine.

Before discussing your specific questions, I would like to discuss more generally the issue of how compliance is determined in situations where a standard does not specify a particular test condition. In issuing Federal motor vehicle safety standards, NHTSA attempts to specify all relevant test conditions. The agency does this as part of ensuring that its standards are objective and practicable. As a practical matter, however, it is not possible to specify every conceivable test condition. This is particularly true for ones which may only be relevant to as-yet-undeveloped technologies.

In cases where a standard does not specify a particular test condition, we believe there are several relevant factors to consider in interpreting the standard. First, in the absence of specification of a particular test condition, we believe there is a presumption that the requirements need to be met regardless of such test condition, since the standard does not include any language which specifically limits applicability of its requirements to such test condition. For example, where a standard does not specify suspension height, its requirements may need to be met at all heights to which the suspension can be adjusted. Before reaching such a conclusion, however, we also consider the language of the standard as a whole and its purposes. Even if a standard is silent as to a particular test condition, the language of the standard or its purposes may indicate limitations on such test condition. Finally, in situations where a limitation on a particular test condition may appear to be appropriate, we also must consider whether the limitation is sufficiently clear, both with respect to justification and specificity, to be appropriate for interpretation. For example, in a situation where it may appear to be reasonable to limit a particular test condition but it is not obvious what particular limitation should be adopted, it would be inappropriate to select a particular limitation by interpretation. Instead, such a decision should be reached in rulemaking.

I will now address the specific questions asked in your letter.

Standard No. l08, Lamps, Reflective Devices, and Associated Equipment

In asking about Standard No. l08, you stated the following:

NHTSA has previously issued an interpretation of the requirements of FMVSS No. l08; at the request of a confidential applicant and dated February l2, l985, with respect to active suspension equipped vehicles. This interpretation stated that the requirements of FMVSS l08 must be meet (sic),"...at any time in which..." lamps, reflective devices, and associated equipment are to be,"...operated for its intended purpose." Consequently, headlamps, tailamps, stoplamps, the license plate lamp, and side marker lamps, must comply with the location requirements of FMVSS No. l08 whenever the vehicle's ignition is in the "on" postiion. Conversely, reflex reflectors, and turn signal lamps that also function as hazard warning signal flashers must comply with the location requirements when the vehicle's ignition is in either the "on" or "off" position. However, it is Mazda's interpretation that hazard warning flashers are not intended to be operational for a period of days, but rather for a period of hours, at maximum, only.

You then asked two questions, (l) whether Mazda's understanding of the subject NHTSA interpretation is accurate, and (2) whether Mazda's interpretation of the maximum intended operating duration of hazard warning signal flashers is correct.

I note that the February l985 interpretation was written in the context of a vehicle with a variable height system actuated by hydraulic fluid. In that particular system, the hydraulic pressure relaxed over a period of about three hours after the ignition was turned off, with the result that the vehicle assumed a lower height than it would have during driving. NHTSA stated the following:

We believe that the minimum height requirement should be met for any lamp at any time in which it is operated for its intended purpose. Since vehicles at rest do not require use of headlamps, the minimum height requirement would be measured at the point after the ignition is on and when the car begins to travel (your letter implies that the time lag between turning on the ignition and restoration of a complying mounting height is a matter of seconds). On the other hand, the hazard warning signal lamps are frequently operated when the vehicle is stopped, and therefore the minimum mounting height of turn signal lamps, through which they operate, must be met with the ignition off, even if the system requires three hours to deplete itself and lower the vehicle to its minimum height.

With respect to your question of whether Mazda's understanding of the interpretation is correct, I would like to note two points. First, while you state that "the requirements of FMVSS l08" must be met at any time in which lamps, reflective devices, and associated equipment are to be operated for their intended purpose, our interpretation was limited to standard's minimum height requirement. While we are prepared, if asked, to address other requirements, our interpretations should be understood to be limited to their specific facts and conclusions. Second, while our interpretation only addressed headlamps and hazard warning signal lamps, you applied the interpretation for headlamps to taillamps, stoplamps, the license plate lamp, and side marker lamps, and the interpretation for hazard warning signal lamps to reflex reflectors. We concur with this application, with respect to Standard No. l08's minimum height requirement.

We do not agree with Mazda's suggested interpretation of the maximum intended operating duration of hazard warning signal flashers. You would apparently like us to conclude that Standard No. l08's minimum height requirement for hazard warning signal flashers does not apply after a vehicle's ignition has been turned off for a matter of days.

In addressing how Standard No. l08 applies in the absence of a specification for vehicle height, our February l985 interpretation differentiates between situations where the vehicle is operating and where it is not. Looking at the purposes of the requirements in question, we believe it is obvious that the minimum height requirement for headlamps is only relevant in situations where the vehicle is operating, while the minimum height for hazard warning signal lamps is also relevant to situations where the vehicle is stopped and the ignition turned off. However, we believe that any determination that Standard No. l08's minimum height requirement for hazard warning signal flashers should not apply after a specified number of hours after the ignition has been turned off is one that would need to be addressed in rulemaking.

It is therefore my opinion that the minimum mounting height of hazard warning signal lamps must be met at all heights with the ignition off, even if the system requires days to deplete itself and lower the vehicle to its minimum height. If you believe that a time limitation should be placed on this requirement, I note that you can submit a petition for rulemaking requesting such a change.

Standard No. lll, Rearview Mirrors

You requested an interpretation of section S5.l.l of Standard No. lll, which generally requires a passenger car's rearview mirror to "provide a field of view with an included horizontal angle measured from the projected eye point of at least 20 degrees, and sufficient angle to provide a view of level road surface extending to the horizon beginning at a point not greater than 200 feet to the rear of the vehicle...." You noted that since the specified procedures for determining the location of the driver's eye reference points are made referenced to points with the vehicle's cabin, your active suspension system would not affect these measurements. However, different vehicle heights would be relevant to whether there is a view of level road surface extending to the horizon beginning at a point not greater than 200 feet to the rear of the vehicle. You stated that, based on "intended purpose," Mazda's interpretation of Standard No. lll is that the requirements of this standard are to be met when the vehicle's ignition is in the "on" position as rearview mirrors are not intended to be used when the vehicle's engine is not operating.

You then asked two questions, (l) whether Mazda's interpretation of the requirements of FMVSS No. lll with respect to the state of the vehicle's ignition switch is correct, and (2) for the purposes of compliance testing to the requirements of FMVSS No. lll, what means of maintaining the intended suspension height for a given speed and operating condition would be satisfactory to NHTSA.

We agree that the field of view requirement specified in S5.l.l for rearview mirrors need not be met for vehicle heights that only occur when the engine is not on, since the requirement is only relevant in situations where the vehicle is operating. However, the requirement would need to be at all vehicle heights that occur during vehicle operation, under the loading conditions specified in S5.l.l.

With respect to the issue of how suspension height should be maintained for purposes of compliance testing, you note early in your letter that, for reasons of practicality and safety, a vehicle's engine is not actually operational during compliance testing. However, since the active suspension system derives its power from the vehicle's engine, the system's ability to maintain and regulate suspension height is only possible during engine operation. You therefore indicated that Mazda is seeking guidelines (for several standards) by which Mazda may be able to establish a means to maintain the intended suspension height for compliance testing purposes in the absence of engine operation.

We are not able, in an interpretation, to specify a particular means for maintaining suspension height for compliance testing in the absence of engine operation. However, the basic principle that should be followed in selecting a means for maintaining suspension height is that it should not result in different test results than would occur if testing could be conducted with suspension height being maintained by engine operation, i.e., what would happen in the real world. This should be relatively straightforward for section S5.l.l of Standard No. lll, since the test is static. For a crash test, it is important that a vehicle not be altered in any way that would change the vehicle's crash performance relevant to the aspect of performance being tested.

Standard No. 204, Steering Control Rearward Displacement

In asking about Standard No. 204, you stated the following:

Section S4 of this standard specifies the compliance parameter for this standard. Section S5 specifies the testing conditions to determine compliance with this standard. Section S5.l specifies that the vehicle be loaded to its unloaded vehicle weight. Section S5.5 specifies that the vehicles fuel tank be filled with Stoddard solvent to any capacity between 90 and 95 percent of the total capacity of the tank. Mazda's interpretation of the requirements of this standard is that they are to be met when the vehicle's ignition switch is in the "on" position only. Furthermore, Mazda interprets the vehicles suspension height pursuant to S5.l and S5.5 to be the intended suspension height for the vehicle given the conditions of S4, i.e., 30 mph vehicle speed and steered wheels are positioned straight ahead.

You then asked whether Mazda's interpretation of the requirements of FMVSS No. 204 are correct. As discussed below, we agree that Standard No. 204's requirements need to be met only at the suspension height that occurs at a 30 mph vehicle speed and with steered wheels positioned straight ahead.

Standard No. 204 specifies requirements limiting the rearward displacement of the steering control into the passenger compartment to reduce the likelihood of chest, neck, or head injury. These requirements must be met in a 30 mile per hour perpendicular impact into a fixed collision barrier. While the standard specifies a number of test conditions, it does not specify suspension height.

Looking at the Standard No. 204 as a whole, we believe it is clear that NHTSA explicitly decided to limit the standard's evaluation of steering control rearward displacement to how vehicles perform in 30 mph perpendicular impacts, even though the requirements have relevance at lower and higher speeds. Therefore, we agree that the standard's requirements need to be met only at suspension heights that occur at a 30 mph vehicle speed and with steered wheels positioned straight ahead.

With respect to Mazda's question concerning means of maintaining intended suspension height for compliance testing, please see our discussion provided with respect to Standard No. lll.

Standard No. 208, Occupant Crash Protection

In asking about Standard No. 208, you stated the following:

Section S8.l.l(d), "Vehicle test attitude," specifies the procedure for determining the vehicle test attitude that is to be used for testing. Specifically, this section requires that the vehicle's pretest attitude, "...shall be equal to either the as delivered or fully loaded attitude or between the as delivered and fully loaded attitude." The as delivered attitude is defined by S8.l.l(d) as being, "...the distance between a level surface and a standard reference point on the test vehicle's body, directly above each wheel opening, when the vehicle is in its "as delivered" condition. The "as delivered" condition is the vehicle as received at the test site..." Because it is highly likely that the test vehicle will not have been operated for a period of days prior to arriving at the test site, the suspension height may have fallen by "y" mm. The fully loaded attitude is defined as the attitude of the vehicle when loaded in accordance with S8.l.l(a) or (b) and a determination of the height of the suspension at the fully loaded condition is made from the same level surface, using the same standard reference points, as were used to determine the "as delivered" condition. The definition of the "as delivered" condition is quite clear. However, Mazda interprets the "fully loaded condition" of the vehicle to be the condition when the vehicle's ignition is "on." In this instance it is likely that the height of the standard reference points on the vehicles body when in the "fully loaded condition" relative to the level surface will be greater than for the "as delivered" condition. Conversely, conventional vehicle suspension systems will likely have an "as delivered" height greater than the "full loaded" height. However, this fact is of no importance as S8.l.l(d) states that the pretest vehicle attitude may be, "...between the as delivered and the fully loaded attitude." With respect to the injury criteria specified by section S6 of this standard, Mazda's interpretation is that these criteria must be met with the vehicle's ignition in the "on" position only.

You then asked three questions, (l) whether Mazda's interpretation of the definition of the "fully loaded condition" is correct with respect to the condition of the ignition switch, (2) whether Mazda's interpretation of the irrelevance of the relative relationship between the "as delivered" and "fully loaded" conditions is correct, and (3) whether Mazda's interpretation of the meaning of "between the as delivered and the fully loaded attitude" is correct.

In addressing your questions, I will begin by noting that Standard No. 208 specifies occupant protection requirements which must be met in specified crash tests at any impact speed up to and including 30 mph. While the standard specifies a number of test conditions, it does not specify suspension height. However, the standard does specify vehicle attitude, which is closely related to suspension height. In addressing how Standard No. 208 applies in the absence of a specification for vehicle height, the relationship between the standard's attitude specification and vehicle height must be considered.

Section S8.l.l(d) specifies the attitude of the vehicle during testing, i.e., the angle of the vehicle relative to the ground. This test condition ensures that the vehicle is not overly tilted toward the front or back, or to one side. The section accomplishes this purpose by specifying that, during a compliance test, the height of the vehicle at each wheel is within a specified range. This range, which may be somewhat different for each wheel, is determined by looking at the vehicle in the "as delivered" condition and the "fully loaded" condition. A vehicle must meet the requirements of Standard No. 208 when its height at each wheel is anywhere within the specified ranges.

On first glance, one might read section S8.l.l(d) to create a height requirement, since ranges of height are determined under that section (at each wheel). This would be incorrect, except in a very narrow sense, since Standard No. 208 does not specify, for vehicles with variable height suspension systems, what suspension height should be used in the two conditions ("as delivered" and "fully loaded") where the specified ranges of height are determined under section S8.l.l(d).

Looking at the Standard No. 208 as a whole, we believe it is clear that NHTSA explicitly decided to limit the standard's evaluation of occupant crash protection in frontal impacts to how vehicles perform in impacts of 30 mph or less, even though the requirements also have relevance at higher speeds. It is our interpretation that the frontal crash test requirements need to be met at all suspension heights that can occur at speeds of 30 mph or less, with the vehicle operational. It is also our interpretation that the crash test requirements need to be met only at suspension heights that can occur at the speed used in the crash test.

A remaining issue is how section S8.l.l(d) applies for vehicles with variable height suspension systems. As discussed below, vehicle attitude should be determined under this section using the actual suspension setting (or equivalent, if the setting is automatic) to be used in a crash test.

For purposes of illustration, I will assume a vehicle with two very different suspension height settings. It would not be appropriate to conclude that the ranges of height determined under section S8.l.l(d) should simultaneously cover both suspension heights. Such ranges would be very large, and would not ensure that the vehicle is not overly tilted toward the front or back, or to one side. Moreover, such ranges would not be relevant to the real world, with respect to vehicle attitude.

Traditional vehicles can be viewed as having a single suspension "setting." This single suspension condition is used in determining vehicle attitude under section S5.8.8.l. The ranges of height result from the differences in loading under the "as delivered" and "fully loaded" conditions.

A single suspension "setting" (or equivalent, if the setting is automatic) should similarly be used in determining vehicle attitude for vehicles with variable height suspension systems. The "setting" should be the one to be used in a crash test.

With respect to Mazda's question concerning means of maintaining intended suspension height for compliance testing, please see our discussion provided with respect to Standard No. lll.

You also asked for an interpretation of section S8.2.7 of Standard No. 208. That section specifies additional conditions to be used for lateral moving barrier crash testing. Section S8.2.7(a) states that the vehicle is at rest in its "normal attitude." You stated that Mazda interprets the meaning of "normal attitude" to be that vehicle attitude which is intended when the vehicle's ignition is in the "on" condition, with the vehicle loaded pursuant to S8.l.l(a) or (b), and while the vehicle is at rest.

Standard No. 208 provides manufacturers the option of either equipping their vehicles with safety belts or meeting certain alternative requirements, including lateral moving barrier crash test requirements. These requirements are relevant at all vehicle heights that can occur during vehicle operation, regardless of speed. Moreover, NHTSA has not decided to limit the standard's evaluation of this aspect of safety performance to how vehicles perform at certain limited speeds. It is our interpretation that the lateral moving barrier crash test requirements, if applicable, must be met at all suspension heights that can occur with the vehicle operational. "Normal attitude" is the attitude determined under section S8.l.l(d). As discussed above, attitude for vehicles equipped with variable height suspension systems is determined under section S8.l.l(d) using the actual suspension setting (or equivalent, if the setting is automatic) to be used in a crash test. Standards No. 2l2, Windshield Mounting; No. 2l9, Windshield Zone Intrusion; No. 30l, Fuel System Integrity

In asking about Standards No. 2l2, No. 2l9, and No. 30l, you noted that NHTSA has previously issued an interpretation to Mazda about how these standards apply to adjustable height suspension systems. In a letter dated August l0, l982, the agency addressed a vehicle equipped with a suspension system having two height positions, one for normal highway driving and another for off-road driving, which could be selected by the driver. NHTSA stated the following:

[Safety Standards No. 2l2, No. 2l9, and No. 30l] do not specify a height adjustment because almost all vehicles have a single, set adjustment. . . . After careful consideration, it is the agency's position that such a vehicle capable of variable height adjustment would have to comply with the vehicle adjusted to any position that is possible. This is true because the vehicle could be driven on the highway, for example, even if it were adjusted to the off-road position. Consequently, it is important that the vehicle comply with the standards in all positions.

You noted that while suspension height could be adjusted by the driver for the system discussed in the agency's previous interpretation, the active suspension system you are currently considering would use an on-board electronic controller to select suspension height, and suspension height would not be adjustable by the driver. Consequently, according to your letter, only one unique set of suspension height parameters is possible for a given vehicle speed and loading condition as is the case with conventional suspension systems. You stated that because it is possible to determine exactly what the intended suspension height should be for a given situation, it is Mazda's opinion that the test vehicle should be tested at the intended suspension height given the specified speed and loading conditions. You also stated that, using an "intended purpose" argument, Mazda concludes that the requirements of the three standards are to be met only when the vehicle's ignition is "on." You then asked whether these suggested interpretations are correct.

Standard No. 2l2 specifies windshield retention requirements that must be met in a specified frontal crash test at any impact speed up to and including 30 mph. Similarly, Standard No. 2l9 specifies windshield zone intrusion requirements that must be met in a specified frontal crash test at any impact speed up to and including 30 mph. Standard No. 30l specifies fuel system integrity requirements for several specified crash tests. These include a frontal crash test similar to those in Standards No. 2l2 and No. 2l9. Requirements for this test must be met at any impact speed up to and including 30 mph. Other tests include a rear moving barrier crash test, a lateral moving barrier crash test, and a static rollover test.

We agree that the requirements of Standards No. 2l2, No. 2l9, and No. 30l need not be met for vehicle heights that only occur when the engine is not on, since the requirements are only relevant in situations where the vehicle is operating. Looking at the three standards as a whole, we believe it is clear that, for the frontal tests specified by the three standards, NHTSA decided to limit the standards' evaluation of safety performance to how vehicles perform in impacts of 30 mph or less, even though the requirements have relevance at higher speeds. It is our interpretation that the frontal crash test requirements specified by these standards need to be met at all suspension heights that can occur at speeds of 30 mph or less, with the vehicle operational. It is also our interpretation that the crash test requirements need to be met only at suspension heights that can occur at the speed used in the crash test.

We reach a different conclusion for Standard No. 30l's other crash test requirements. These requirements are relevant at all vehicle speeds and suspension heights. Moreover, NHTSA has not decided to limit the standard's evaluation of these aspects of safety performance to how vehicles perform at certain limited speeds. It is our interpretation that these crash test requirements must be met at all suspension heights that can occur with the vehicle operational.

Part 58l Bumper Standard

In asking about the Part 58l Bumper Standard, you noted that NHTSA has previously issued several interpretations of how the standard applies to vehicles with adjustable height suspension systems. In a letter to Subaru dated May 6, l986, NHTSA stated the following:

Given the absence of a specific test condition concerning suspension height, it is our interpretation that a vehicle must be capable of meeting the standard's damage criteria at any height position to which the suspension can be adjusted. There is no language in the test requirements of the standard limiting their applicability to "the manufacturer's nominal design highway adjusted height position."

This interpretation is consistent with the purpose of the Bumper Standard, set forth in section 58l.2, to reduce physical damage to the front and rear ends of a passenger motor vehicle from low speed collisions. If a vehicle's suspension could be adjusted so that its bumper height resulted in bumper mismatch with other vehicles in the event of low speed collisions, the reduction in physical damage attributable to the Bumper Standard would be defeated in whole or part.

In another letter, dated February l2, l985, NHTSA stated that a vehicle is "required to meet the pendulum test of Part 58l in any vehicle use scenario in which the vehicle operates, and the barrier test of Part 58l when the engine is idling."

You suggested, for the barrier test, that the agency's May l986 interpretation may be inappropriate for your active suspension system, since your system provides for only one suspension height when the engine is idling. You also suggested, for the pendulum test, that these interpretations seem to be in conflict with the Bumper Standard's stated purpose to reduce physical damage to motor vehicles in low speed collisions. We assume that you are referring to the fact that your suspension system has heights that occur only at speeds greater than 35 mph. You then requested that NHTSA provide an interpretation of Part 58l with respect to your system.

In addressing how Part 58l applies to vehicles equipped with an active suspension system, I will address separately the standard's barrier and pendulum tests. For the barrier test, a vehicle must meet specified damage criteria after an impact into a fixed barrier that is perpendicular to the line of travel of the vehicle, at 2.5 mph. Section 58l.6 sets forth conditions applicable to bumper testing. Under section 58l.6(c), at the onset of a barrier impact, the vehicle's engine is operating at idling speed.

Looking at the Bumper Standard as a whole, we believe it is clear that NHTSA decided to limit the barrier test's evaluation of bumper performance to how vehicles perform in 2.5 mph frontal impacts, even though the requirements have relevance at lower and higher speeds and when the vehicle is nonoperational. It is our interpretation that the barrier test requirements specified by this standard need to be met at all suspension heights that can occur at 2.5 mph.

We reach a different conclusion for the pendulum test, which serves the purpose of creating a bumper height requirement. This requirement is relevant at all vehicle speeds and suspension heights, and when the vehicle is nonoperational. I note that while Mazda is correct that the Bumper Standard's stated purpose is to reduce physical damage to motor vehicles in low speed collisions, NHTSA has justified the bumper height requirement on safety concerns related to "higher speed collisions." In proposing Standard No. 2l5, the predecessor of Part 58l, the agency stated:

. . . in higher speed collisions the tendency of a bumper to override another or to ride under or over a guardrail creates hazards for vehicle occupants. Vehicles with interlocking bumpers block traffic and expose their occupants to considerable danger, particularly if they attempt to get out to unlock bumpers. By overriding or underriding a guardrail, a bumper may strike a supporting post, or similar fixed object, with serious consequences for the vehicle and its occupants. 35 FR l7999, November 24, l970.

The relevance of the bumper height requirement to nonoperational situations is also clear, e.g., to help protect parked cars.

Moreover, NHTSA has not decided to limit the bumper height requirement to how vehicles perform at certain limited speeds. It is our interpretation that the pendulum test requirements must be met at all suspension heights that can occur, regardless of vehicle speed or whether the ignition is turned on.

This interpretation is consistent with an October l8, l978 letter to Nissan, in which NHTSA addressed how the pendulum test applies to vehicles equipped with height control systems, including automatic height control systems. Among other things, the agency stated the following:

. . . There is no language in the pendulum test requirements of the standard which would limit their applicability to only the ignition-on or ignition-off situation or to the recommended driving position for normal roadways. The vehicle must be capable of meeting the pendulum test requirements at all stable bumper heights possible at unloaded vehicle weight.

Thus, in the situations described in Question l and 2 of your letter, in which an automatic height control system is employed, the vehicle must comply with the pendulum test requirements in both the ignition-on and ignition-off positions . . . .

I note that one of our past letters, a December 24, l984 letter addressed to Porsche, appears to suggest that the pendulum test must be met in any setting in which the system operates "when the engine is idling." This might be read to suggest that the pendulum test need not be met when the vehicle is nonoperational. However, this interpretation cited section 58l.6(c) in concluding that the engine is idling during Part 58l testing. Section 58l.6(c) applies only to the barrier test and not the pendulum test. We therefore consider this interpretation to be incorrect to the extent that it is inconsistent with the analysis presented above.

Sincerely,

Paul Jackson Rice Chief Counsel

ref:l08#lll#204#208#2l2#2l9#30l#58l d:l0/2/90

ID: 1653y

The Honorable Jim Bates
Member, U.S. House of Representatives
430 Davidson St., Suite A
Chula Vista, CA 92010

Dear Mr. Bates:

This is in reply to your letter of October 19, l988, with reference to an invention by your constituent, Angelo R. Collica. You have asked for "the requirements necessary to install lighting devices on motor vehicles."

Since we do not have a description of Mr. Collica's device, our answer must therefore be general in nature. There are different answers, depending upon whether a device is installed before or after the first sale of a vehicle.

A supplementary lighting device installed on a vehicle by a vehicle manufacturer or dealer before its first sale to a consumer is permissible as long as it does not impair the effectiveness of lamps, reflective devices, and associated equipment that are required by the Federal motor vehicle safety standard on lighting. Examples of impairment are diminished brightness of a lamp due to interference with its wiring, or a confusion of its function through close proximity or signal of the supplementary device. In general, also, all lighting equipment other than hazard warning/turn signals, and headlamps flashed for signalling purposes, must be steady-burning in use. Whether a device creates an impairment is a determination to be made by the vehicle manufacturer in its certification of compliance with the Federal safety standards, or by the dealer, before sale of the vehicle.

The installation of a supplementary lighting device on a vehicle after the vehicle's first sale to a consumer is acceptable under Federal law, provided that the installation does not degrade the performance of any device or element of design installed in accordance with any Federal motor vehicle safety standard. This prohibition applies to vehicle manufacturers, distributors, dealers and repair businesses. It does not, however, apply if the supplementary lighting device is installed by the vehicle owner.

The legality of operating a supplementary device, installed after vehicle sale, is primarily determinable under the laws of any State in which a vehicle using it is registered or driven. The American Association of Motor Vehicle Administrators, 4600 Wilson Blvd., Arlington, Va. 22203, is able to advise on State laws.

I hope that this has been helpful to you.

Sincerely,

Diane K. Steed

/ref:108 d:l/23/89

ID: aiam1685

Dear Mr. Gibson: This is in response to your letter of October 21, 1974, inquiring as t the effect of Federal Motor Vehicle Safety Standard No. 121 on State laws relating to air brake performance. You ask whether California can impose requirements pertaining to parking brake release (on trucks and buses) and trailer emergency braking capability which differ from provisions contained in the Federal standard.; Section 103(d) of the National Traffic and Motor Vehicle Safety Act o 1966 (15 U.S.C. 1392(d)) provides that no State or political subdivision of a State may promulgate or continue in effect standards applicable to an aspect of motor vehicle or motor vehicle equipment performance which is covered by a Federal motor vehicle safety standard, unless the standards are identical.; Standard 121 includes provisions relating to truck and bus parkin brake performance and specifies requirements for an emergency braking capability on trailers. Promulgation by a State of a more restrictive parking brake requirement providing for the installation of a release not specified in the Federal standard is prohibited by S 103(d) since the Federal standard is intended to cover all aspects of parking brake performance. A State requirement specifying application of trailer service brakes on breakaway would also be preempted by Standard 121 since Section S5.8 of the Federal standard addresses the subject of emergency trailer braking capability.; The Federal requirements must be regarded as conclusive with regard t parking brake performance and emergency braking capability in order to maintain the uniformity necessary in a Federal regulatory scheme. If States were permitted to impose additional requirements in an area regulated by a Federal safety standard manufacturers would be confronted with an impossible task of compliance. This reasoning formed the basis of a recent decision rendered in a case brought by the Motorcycle Industry Council, Inc. against the State of California in the United States District Court for the Eastern District of California concerning the preemption of a California State requirement that motorcycle headlamps be wired to operate when the engine is running. The Court held that the California requirement is preempted by the Federal Motor Vehicle Safety Standard No. 108 since the NHTSA intended to cover all aspects of performance directly involving motorcycle headlamps.; Therefore, requirements such as those described in your letter would b preempted by Standard 121 since the aspects of performance that would be affected are covered by the Federal standard.; You also ask if your interpretation of Standard No. 121 t International Harvester is correct. In answer, I would like to set out a comprehensive explanation of the standard's requirements for parking brakes (S5.6) in relation to the requirements for emergency braking capability (S5.7, S5.8). I have separated the requirements for trailers from those for trucks, and further separated the truck requirements into the 'automatically-applied parking brake' systems (S5.7.1) and the 'modulated' systems (S5.7.2).; *Trailer brake requirements (other than trailer converter dollies)*. I addition to the requirement for a trailer service brake system (S5.3, S5.4), Standard No. 121 specifies that each air-braked trailer be equipped with an emergency capability (S5.8) and a parking brake (S5.6). The emergency braking capability calls for an automatic application of the parking brake system in the event the air pressure in the supply line is lost. This requirement ensures a back-up braking system in cases of service brake failure and brakes on the trailer in the event of a trailer break away.; The parking brake requirements for trailers specify that the brakes b applied by an energy source that is not affected by loss of air pressure in the service brake system and that, once applied, the parking brakes be held in the applied position solely by mechanical means. The common method to meet this requirement is, of course, to use springs to apply and hold the friction elements of the service brake system. The requirements are intended to ensure that a parked vehicle will not lose its brakes if air is lost from the system by leakage.; The NHTSA recognizes that automatic application of the 'spring brakes (as an emergency capability) could cause a safety problem if they could not be released to move the disabled vehicle from the roadway. For this reason, S5.2.1.1 specifies that each trailer be equipped with a protected reservoir that is capable of releasing the vehicle's parking brakes at least once.; Your interpretation that Standard No. 121 requires control of this tan from the driver's position after an automatic application of the parking brakes is incorrect. The parking brake requirements of S5.6 specify a system for holding stationary a vehicle (or combination) which has a totally functioning brake system. Therefore, S5.6.4 does not establish requirements for application and release of the parking system of the towed vehicle in an emergency when, for example, a supply line to the towed vehicle has burst. The requirement of S5.7.2.2 that parking brakes remain operable is not addressed to trailers.; You pointed out in your July 11, 1973, comments to the docket that th standard should be amended to require that the trailer's protected tank be equipped with a manual valve that releases the parking brakes to permit moving a disabled trailer from the roadway. We are preparing a proposal on parking brake systems in response to an American Trucking Associations petition, which may be responsive to your suggestions.; *Truck (and bus) requirements*. In addition to the requirement for service brake system (S5.3, S5.4), Standard No. 121 specifies that each air-braked truck (and bus) be equipped with an emergency braking capability (S5.7) and a parking brake system (S5.6).; The parking brake requirements of S5.6, as noted above, specify system for holding stationary a vehicle (or combination) which as a totally functioning brake system. S5.6.4 does not therefore establish control requirements in the event of a failure in the system. Only the brake control requirements listed in S5.7 are required during and after a stop which follows a failure in the service brake system.; Section S5.7 permits the manufacturer to provide the emergency brak capability and associated controls in one of two ways: automatically-applied parking brakes (S5.7.1) or a modulated braking capability (S5.7.2). To our knowledge few if any manufacturers have chosen to build an emergency system which conforms to S5.7.1. Because the International Harvester (IH) system and those of other manufacturers conform to S5.7.2, the following discussion addresses only that option.; S5.7.2 specifies an emergency braking capability which can stop th truck or bus within a certain distance in the event of a failure of the service brake system other than a failure of a common valve, manifold, brake fluid housing, or brake chamber housing (S5.7.2.3). When a failure of this type occurs in the truck, S5.7.2.1 specifies that the towing vehicle emergency brake system control be capable of controlling service or parking brakes on any towed vehicle equipped with air brakes. This does not mean that control must be exercised over the trailer brakes if a failure occurs in the supply line or control line to the trailer.; S5.7.2.2 specifies a dynamic braking capability in the parking brak system (subject to manual application) in the event of a total failure of the service- emergency braking capability.; From a study of the brake system schematics for the IH split syste (with spring brakes), it appears that the system would comply with Standard No. 121. In your letter to IH you conclude that their system does not comply 'since the spring brake [on the truck] can not be released when the service air is lost.' You base your interpretation on language of S5.7.2.2 that 'loss of air [due to failure in both service and emergency modes] shall not cause the parking brake to be inoperable'. Your concern is that a failure of this nature would prevent a disabled vehicle from being moved from the roadway if the parking brake is not releasable.; As earlier noted, S5.7.2.2 specifies a dynamic parking brake capabilit in the event of catastrophic failure. This section is not a requirement that the parking brake operate as it would in a totally functioning and stationary vehicle. Such a requirement in S5.7.2 for release of the parking brakes to move the vehicle is impractical with some of the specified failures. Moreover, it is also unnecessary, because a modulated emergency system provides a driver with several applications and releases of the emergency brake system to move the disabled vehicle off the road after the signal from the warning system (S5.1.6) that the vehicle has lost its service brake system. These applications are the equivalent of the California requirement that the spring brake system be capable of being applied, released, and reapplied by the driver, following notice of the service brake system failure, as indicated by an automatic brake application.; You make the statement that IH must meet the requirements of S5.7.1. because its parking brakes apply automatically after both the service system fails and the emergency system is depleted. In fact IH has chosen to meet S5.7.2 and is not required to meet any of the specifications of S5.7.1.; Because these differences exist between the present Californi regulations and the soon-to-be-implemented Federal requirements, manufacturers like International Harvester will have difficulty in effecting an orderly transition to the new systems. We have encouraged manufacturers to introduce the new systems in small numbers before the effective date to gain some experience with them, and we feel that it would be unfortunate if these manufacturers were penalized by the States for their early introductions.; I invite comments from the State of California on our upcoming parkin brake system proposal.; Yours truly, Richard B. Dyson, Acting Chief Counsel

ID: 0473

Mr. John Sheppard
Sales and Marketing Manager
Reflexite Canada, Inc.
6790 Kitimat Road, Unit 18
Mississauga
Ontario L5N 5L9
Canada

Dear Mr. Sheppard:

We have received your letter of November 2, 1994, asking whether certain conspicuity material could be used on trailers required to meet S5.7 of U.S. Federal Motor Vehicle Safety Standard No. 108. You have enclosed samples of the material.

The material alternates red and white stripes "oriented at a 45 degree angle to the edge of the roll." Rolls are either 6 or 8 inches in width and "will not have DOT-C2 marking." In addition, we note that the horizontal length of the red segments is 5 1/2 inches (and presume an equal length for the white segments). Specifically, you have asked whether this material could "be applied to the lower edge of the vehicle's rear doors as a compliant substitute for the 2" 'block pattern' material currently being used?"

Paragraph S5.7's specifications for conspicuity material are intended to ensure uniformity of treatment in order to enhance the ability of drivers of other vehicles to detect large objects in the roadway under conditions when headlamps are used. While S5.7 does not require that the red and white color segments be rectangular, it does establish requirements for their length and width. Under S5.7.1.3(b), each segment shall have a length of 300 mm +/- 150 mm. The color segment separation of 5 1/2 inches on your sample is approximately 140 mm, and thus below the minimum permitted by the standard. Although currently, under S5.7.1.3(d), three widths of retroreflective material are permissible: 50 mm (DOT-C2), 75 mm (DOT-C3), and 100 mm (DOT-C4) and your widths of 6 inches (150 mm) and 8 inches (200mm) do not conform to these specifications, the agency has proposed that these be minimum minimum widths for the DOT grades indicated. We expect a final rule to be issued on this proposal in the near future.

Because the retroreflective material discussed above would not comply with Standard No. 108's requirements for color segment length (and currently width), it could not be used as a substitute for the DOT-C2 material that you currently manufacture. Further, geometrically and photometrically complying material would require the appropriate DOT grade identification marking for use on a trailer required to comply with Standard No. 108.

Sincerely,

Philip R. Recht Chief Counsel ref:108 d:12/7/94

ID: nht89-1.6

TYPE: INTERPRETATION-NHTSA

DATE: 01/23/89

FROM: DIANE K. STEED -- NHTSA

TO: JIM BATES -- MEMBER, U.S. HOUSE OF REPRESENTATIVES

TITLE: NONE

ATTACHMT: LETTER DATED 10/19/88 FROM JIM BATES -- CONGRESS TO DIANE K. STEED

TEXT: Dear Mr. Bates:

This is in reply to your letter of October 19, 1988, with reference to an invention by your constituent, Angelo R. Collica. You have asked for "the requirements necessary to install lighting devices on motor vehicles."

Since we do not have a description of Mr. Collica's device, our answer must therefore be general in nature. There are different answers, depending upon whether a device is installed before or after the first sale of a vehicle.

A supplementary lighting device installed on a vehicle by a vehicle manufacturer or dealer before its first sale to a consumer is permissible as long as it does not impair the effectiveness of lamps, reflective devices, and associated equipment that are required by the Federal motor vehicle safety standard on lighting. Examples of impairment are diminished brightness of a lamp due to interference with its wiring, or a confusion of its function through close proximity or signal of the supplementary devi ce. In general, also, all lighting equipment other than hazard warning/turn signals, and headlamps flashing for signalling purposes, must be steady-burning in use. Whether a device creates an impairment is a determination to be made by the vehicle manu facturer in its certification of compliance with the Federal safety standards, or by the dealer, before sale of the vehicle.

The installation of a supplementary lighting device on a vehicle after the vehicle's first sale to a consumer is acceptable under Federal law, provided that the installation does not degrade the performance of any device or element of design installed in accordance with any Federal motor vehicle safety standard. This prohibition applies to vehicle manufacturers, distributors, dealers and repair businesses. It does not, however, apply if the supplementary lighting device is installed by the vehicle own er.

The legality of operating a supplementary device, installed after vehicle sale, is primarily determinable under the laws of any State in which a vehicle using it is registered or driven. The American Association of Motor Vehicle Administrators, 4600 Wil son Blvd., Arlington, Va. 22203, is able to advise on State laws.

I hope that this has been helpful to you.

Sincerely,

ID: nht94-4.99

TYPE: INTERPRETATION-NHTSA

DATE: December 7, 1994

FROM: Philip R. Recht -- Chief Counsel, NHTSA

TO: John Sheppard -- Sales and Marketing Manager, Reflexite Canada, Inc.

TITLE: None

ATTACHMT: ATTACHED TO LETTER DATED 11/2/94 FROM JOHN SHEPPARD TO CHIEF COUNCIL, NHTSA (OCC 10473)

TEXT: We have received your letter of November 2, 1994, asking whether certain conspicuity material could be used on trailers required to meet S5.7 of U.S. Federal Motor Vehicle Safety Standard No. 108. You have enclosed samples of the material.

The material alternates red and white stripes "oriented at a 45 degree angle to the edge of the roll." Rolls are either 6 or 8 inches in width and "will not have DOT-C2 marking." In addition, we note that the horizontal length of the red segments is 5 1/ 2 inches (and presume an equal length for the white segments). Specifically, you have asked whether this material could "be applied to the lower edge of the vehicle's rear doors as a compliant substitute for the 2" 'block pattern' material currently bein g used?"

Paragraph S5.7's specifications for conspicuity material are intended to ensure uniformity of treatment in order to enhance the ability of drivers of other vehicles to detect large objects in the roadway under conditions when headlamps are used. While S 5.7 does not require that the red and white color segments be rectangular, it does establish requirements for their length and width. Under S5.7.1.3(b), each segment shall have a length of 300 mm +/- 150 mm. The color segment separation of 5 1/2 inches on your sample is approximately 140 mm, and thus below the minimum permitted by the standard. Although currently, under S5.7.1.3(d), three widths of retroreflective material are permissible: 50 mm (DOT-C2), 75 mm (DOT-C3), and 100 mm (DOT-C4) and your widths of 6 inches (150 mm) and 8 inches (200mm) do not conform to these specifications, the agency has proposed that these be minimum minimum widths for the DOT grades indicated. We expect a final rule to be issued on this proposal in the near future.

Because the retroreflective material discussed above would not comply with Standard No. 108's requirements for color segment length (and currently width), it could not be used as a substitute for the DOT-C2 material that you currently manufacture. Furth er, geometrically and photometrically complying material would require the appropriate DOT grade identification marking for use on a trailer required to comply with Standard No. 108.