ID: nht90-4.58

TYPE: Interpretation-NHTSA

DATE: November 9, 1990

FROM: Paul Jackson Rice -- Chief Counsel, NHTSA

TO: William Shapiro -- Manager, Regulations and Compliance, Volvo Cars of North America

TITLE: None

ATTACHMT: Attached to letter dated 8-27-90 from W. Shapiro to P.J. Rice

TEXT:

This responds to your request for an interpretation of Standard No. 210, Seat Belt Assembly Anchorages (49 CFR S571.210). More specifically, you asked about the anchorage location requirements for the upper torso portion of Type 2 safety belts (i.e., la p/shoulder belts), set forth in S4.3.2 of Standard No. 210. I am pleased to have this opportunity to explain those regulatory requirements for you.

Before discussing the substantive issues raised in your letter, I would like to respond to your request that NHTSA not publicly release the design drawings for this proposed new safety belt design. We hereby grant your request. We will make available t o the public your incoming letter and this response, but not the design drawings.

Your letter stated that Volvo is designing lap/shoulder belts for the rear seating positions of proposed future vehicles. The retractor for the upper end of the shoulder belt portion of these safety belts would be located in the seat back, and not withi n the acceptable anchorage location zone shown in Figure 1 of Standard No. 210. However, the shoulder belt webbing would pass through a device on the top of the seat back that you called a "belt anchor" on the way to the retractor. This "belt anchor" w ould bear most of the loads imposed on the shoulder belts from the forward direction, and would redirect the shoulder belt webbing downward to the retractor. This function is similar to that performed by D-rings for many current designs of manual lap/sh oulder safety belts. The "belt anchor" would be within the acceptable anchorage location zone shown in Figure 1 of Standard No. 210. You asked if this design would comply with the requirements of S4.3.2 of Standard No. 210. The answer to your question is yes.

Both the "belt anchor" and the retractor would be "anchorages" within the meaning of S3 of Standard No. 210 for the shoulder belt, because both would transfer belt loads to the vehicle structure. However, S4.3.2 does not require that both these anchorag es comply with the anchorage location requirements. Instead, S4.3.2 provides that, "the seat belt anchorage for the upper end of the upper torso restraint shall be located within the acceptable range shown in Figure 1." NHTSA has interpreted this langu age as follows. If there is a single "anchorage" for the upper end of the shoulder belt, that single "anchorage" must comply with the anchorage location requirements. If there is more than one "anchorage" for the upper end of the shoulder belt, the upp ermost of these multiple anchorages must comply with the anchorage location requirements.

I hope this information is helpful. Please let me know if you have any further questions or need some additional information on this subject.

ID: nht90-4.59

TYPE: Interpretation-NHTSA

DATE: November 9, 1990

FROM: Joe W. Humphrey

TO: Paul Jackson Rice

TITLE: None

ATTACHMT: Attached to letter dated 12-13-90 to J.W. Humphrey from P.J. Rice (A36; Std. 108)

TEXT:

I have an idea for the safety of cars (illegible) for truckers. Will it be excepted in the federal law to add (illegible) lights to the center break lights in the back of cars above the back seat the break light red in the center orange or yellow on each side for (illegible). Lights all of them in the center of the cars for breaks and (illegible) lights only if this is excepted send me letter of approval please sir.

I hope you can understand what I am try to say.

ID: nht90-4.6

TYPE: Interpretation-NHTSA

DATE: September 14, 1990

FROM: Paul Jackson Rice -- Chief Counsel, NHTSA

TO: William Shapiro -- Volvo Cars of North America

TITLE: None

ATTACHMT: Attached to letter dated 8-10-89 from W. Shapiro to S.P. Wood (OCC 3848); Also attached to drawing of child booster seat (graphics omitted)

TEXT:

This responds to your letter about the built-in child seat Volvo has designed for the center rear seating position. The built-in seat uses the vehicle's lap-shoulder safety belt to restrain the child. I regret the delay in responding.

You indicated in a telephone conversation that Volvo is considering designing the seat solely for children who weigh more than 50 pounds. Such a seat is not subject to the requirements of standard 213 because the seat is not a "child restraint" as that t erm is defined in the standard. Paragraph S4 of Standard 213 defines a child restraint system as "any device, except Type I or Type II seat belts, designed for use in a motor vehicle to restrain, seat, or position children who weigh not more than 50 poun ds."

The agency would determine whether your built-in seat is designed solely for children weighing more than 50 pounds by considering available indications of the manufacturer's design intent, e.g., the physical suitability of the seat for use by children wh o weigh less than 50 pounds, and the manner in which the seat is labeled and marketed. The agency would look to see whether the seat is clearly and permanently labeled to show the size and age of children intended to be restrained by the system. We woul d also consider any indications in Volvo's marketing efforts and point of sale materials regarding the size and age of child that the seat is designed to restrain. Finally, we would consider any size and age information included in the vehicle's owner m anual.

You also indicated Volvo may consider designating the seat as suitable for children weighing more than 40 pounds. If the seat were so designated, it would no longer be a seat designed solely for children weighing more than 50 pounds, and therefore be a child restraint system subject to Standard 213.

You ask whether, if Standard 213 applies to your seat, the standard permits such a seat. You state that the seat would meet the labeling and performance requirements of the standard. You believe that Standard 213 permits the seat because the final rule that amended 213 to set requirements directly applicable to built-in seats (53 FR 1783; January 22, 1988) said that paragraph S5.4.3.3 of the standard allows child restraint systems other than a 5-point harness system.

You are correct that the standard does not require the use of a harness in a child restraint system. Paragraph S5.4.3.3 provides, in part, that "each child restraint system . . . that has belts designed to restrain the child" must comply with the specif ic requirements of S5.4.3.3 (i.e.,

provide upper and lower torso restraint, and a crotch restraint (for seats for children weighing over 20 pounds), of a specific form). The definition of a "child restraint system" specifically excludes the vehicle's lap/shoulder belts from the coverage of the standard. Thus, under that definition and the language of S5.4.3.3, the specific requirements of S5.4.3.3 on harness systems applies only to seats that have belts, and not to a seat such as yours that uses the vehicle's belt system.

Please note that Standard 213 sets limits on knee excursion for built-in seats (S5.1.3.1(b)). Thus, although your seat is not required to have a crotch strap, the seat must be designed to prevent a child from sliding excessively forward and down, legs f irst ("submarining").

The agency would like to emphasize its concern that when a vehicle lap belt is used with a child restraint system to restrain a child, the lap belt should be positioned so that it does not apply impact loads to the abdomen of the child, the area most vul nerable to the forces imposed by the belt. Instead, the vehicle lap belt should be held in place by the child restraint so that it passes over the pelvis of a child, the area of the body best able to withstand the forces imposed by the vehicle belt. We cannot determine from your drawing whether the vehicle lap belt would be properly positioned and securely held by the restraint. The instructions for the proper use of the built-in seat that are required by S3.6.2 of the standard should inform users how to properly adjust the belt system, so to avoid submarining and imposing impact loads to the child's abdomen.

The agency is also concerned that the sitting height of some children who may occupy the seat might not be high enough for the shoulder belt to be properly positioned when attached. Instead, the belt might pass in front of the child's neck or face. For those cases, if no other option is available, NHTSA believes that the shoulder belt should be placed behind the child's back. We recommend that you include information in the printed instructions about such adjusting of the shoulder belt for small chil dren. As a reminder, NHTSA will use these adjustment instructions per S6.1.2.3.1 to position the three year old dummy in the seat if the agency tests the seat in its compliance program.

ID: nht90-4.60

TYPE: Interpretation-NHTSA

DATE: November 13, 1990

FROM: M. Iwase -- General Manager, Technical Administration Dept., Koito Manufacturing Company

TO: Paul Jackson Rice -- Chief Counsel, NHTSA

TITLE: Re FMVSS No. 108 (Lamp, reflective devices, and associated equipment) Photometric Measurement Procedures for L.E.D. CHMSL

ATTACHMT: Attached to letter dated 12-17-90 to M. Iwase from Paul Jackson Rice (A37; Std. 108)

TEXT:

We would hereby ask you to provide us with your kind advice concerning photometric measurement procedures for L.E.D. center high-mounted stop lamps (CHMSL).

Photometric output of L.E.D. lighting device decreases as the time passes after activation, as shown in Figure 1. This is caused by the thermal characteristic of L.E.D. discrete itself. Our question is about the timing of photometry when the photometri c output of L.E.D. CHMSL should be measured for the verification of compliance with the photometric requirements of FMVSS No. 108. It is reasonable that it shall be measured when 5 minutes has elapsed after the lamp is energized, with the following reas ons, we think;

(1) Our real-car field test has been performed to see how often and how long foot brake application (stop lamp operation) is raised during actual driving in the certain urban area. As the result of our field test, it was found that the c ontinuance is for 5 minutes at best for our brake application (refer to Figure 2).

(2) Section 3.1.5.3 "Photometric Minumums" in SAE J1889 JUN88 specifies, as follows;

Photometric Minumums: For measurements to photometric minimum requiments, the test "device light output shall first be stabilized by energizing the device at laboratory ambient temperature (23 +/- 5 degrees C) until either internal he at builtup saturation has occured or 30 minutes has elapsed, whichever occurs first.

This provision is true of steady burn lamps, for example tail lamp, parking lamp, etc., however not true of stop lamp which is energized during just the period of service brake operation.

(3) S4.8 "Warpage Test on Devices with Plastic Components" and Table 1 "Cycle Time (Min)" in SAE J575 JUL83 specifies 5-on/5-off operating cycle for stop lamps.

Whether could our interpretation above-mentioned be legally accepted? Upon your kind review, your prompt reply would be highly appreciated.

Attachment

Figure 1. Photometric Output Of L.E.D. And Incandescent Bulb (Graph Omitted) Figure 2. Brake Application Period (Graph Omitted) Test Method: Three (3) vehicles (A, B and C) chosen at random were chased and measured brake application periods. Date: January 10, 1990 Location: Urban area (in Nagoya city)

Remark: Each test data of three vehicles is continuous, namely Vehicle A was measured the brake application for 72 minutes, and Vehicle B and C were measured for 24 minutes, respectively.

ID: nht90-4.61

TYPE: Interpretation-NHTSA

DATE: November 14, 1990

FROM: Jeffrey S. Malinowski -- Small Business Center

TO: Paul Jackson Rice -- Chief Counsel, NHTSA

TITLE: None

ATTACHMT: Attached to letter dated 2-1-91 from Paul Jackson Rice to Jeffrey S. Malinowski (A37; VSA 108(a)(2)(A))

TEXT:

This letter is a request for information in regards to an inventor who has designed a tie rod "safety bracket." He needs to know if it would have to comply with the Code of Federal Regulations.

I am a private consultant employed with the Small Business Center, located in Port Huron, Michigan. I was informed by Mr. Carl Clark from the Department of Transportation that you would be the person to contact for this information.

Product Feature Benefits and Advantages:

This new product is composed of five sub-parts that once installed will require no maintenance and will virtually last the life of the vehicle.

The Product is:

1. Simple in design requiring less than three minutes to install. The bracket can be installed by the do-it-yourselfer.

2. Universal in application, probably requiring less than six different part numbers to fit all the vehicles currently making up the new and used vehicle market.

The Product will:

1. Reduce tie rod end wear by up to 300%, thereby extending the tie rod end life by up to three times its normal life expectancy.

2. Increase safety by eliminating any possible tie rod seperation due to excessive wear.

3. Improve steering by giving the vehicle a tighter response and feel.

We will be waiting for your reply to confirm our belief that the tie rod "safety bracket" does not have to adhere to the Code of Federal Regulations.

Attachment

Diagrams and accompanying text regarding Tie Rod Safety Brackets (for the outer and inner tie rod ends). Invented by Leo McCallum. (Text and graphics omitted)

ID: nht90-4.62

TYPE: Interpretation-NHTSA

DATE: November 20, 1990

FROM: Paul Jackson Rice -- Chief Counsel, NHTSA

TO: Julie Gonzalez -- Keiper Recaro Seating, Inc.

TITLE: None

ATTACHMT: Attached to letter dated 9-21-90 from J. Gonzalez to P.J. Rice (OCC 5253)

TEXT:

This responds to your letter of September 21, 1990 concerning automobile seats your company installs into vehicles on an aftermarket basis. Your letter states;

(t)o complete the installation we use an adapter bracket to mount our seat into the vehicle. In some vehicles we mount our seat onto our adapter bracket and then mount that assembly onto the original equipment manufacturer's seat track. In some of thes e cases the seat belt buckle is attached to the OEM seat. We would like to remove the OEM belt buckle from the OEM seat and attach it to our adapter bracket. ...

In other vehicles we must remove the OEM seat track and use a Recaro seat track. In these cases the Recaro Seat is mounted onto the Recaro seat tracks which mount onto a Recaro adapter bracket that mounts onto the floor. In this situation we would like to mount the OEM seat belt buckle to the adapter bracket which bolts to the floor.

You asked for a list and description of the tests and safety standards which must be met in both of these situations. In subsequent phone conversations with Mary Versailles of my staff, you emphasized that you are only concerned with the effect of movin g the OEM belt buckle, as you have previously determined that the seat itself complies with our standards. Therefore, this letter will be limited to addressing standards relating to safety belts.

The agency has issued the following safety standards that apply to safety belts: Standard No. 208, Occupant Crash Protection, Standard No. 209, Seat Belt Assemblies, and Standard No. 210, Seat Belt Assembly Anchorages. All safety belts sold in the Unite d States must be certified as complying with Standard No. 209, regardless of whether the belts are installed as original equipment in a motor vehicle or sold as a replacement part. However, since you indicate that you do not replace or alter the OEM safe ty belts, it does not appear that you need to be concerned with this standard.

Since Standard No. 208 and Standard No. 210 apply only to new vehicles, they are called vehicle standards. The general rule is that aftermarket equipment does not have to comply with vehicle standards. However, there is one statutory exception to this rule which might affect your modifications. If a vehicle is modified after its first sale, S108(a)(2) (A) of the Vehicle Safety Act provides, in pertinent part:

No manufacturer, distributor, dealer, or motor vehicle repair business shall knowingly render inoperative, in whole or part, any device or

element of design installed on or in a motor vehicle or item of motor vehicle equipment in compliance with an applicable Federal motor vehicle safety standard...

With respect to Standard No. 208, the safety belts and other related occupant crash protection features, potentially including automatic crash protection, are elements of design installed in a motor vehicle in compliance with this safety standard. The " render inoperative, prohibition requires your company to ensure that the vehicles in question will continue to afford the occupant protection required by Standard No. 208, even with a new seat installed and the OEM safety belt buckle repositioned. Since your proposed repositioning of the buckle will change the geometry of the safety belt system, it could certainly affect the occupant protection capabilities of the vehicle. Your company ought to carefully review the proposed repositioning of the buckle in light of the requirements of Standard No. 208.

With respect to Standard No. 210, the repositioning of the buckle could also raise questions under the "render inoperative" prohibition. The location and strength of the safety belt anchorages are elements of design installed in a vehicle in compliance with Standard No. 210. S3 of Standard No. 210 defines the term "seat belt anchorage" as "the provision for transferring seat belt assembly loads to the vehicle structure." Since, according to your letter, the OEM buckle is attached to the OEM seat, we w ould consider the attachment point on the seat to be the anchorage. It is that attachment point that transfers the seat belt load to the vehicle structure. Your modifications would move the anchorage to another location. The "render inoperative" prohi bition requires you to ensure that after repositioning the OEM buckle, the new attachment point complies with the location and strength requirements of Standard No. 210 that applied to the anchorages in the original configuration of the vehicle's safety belts.

You also asked what kind of testing is required. The "render inoperative" provisions in the Safety Act do not require your company to test vehicles after you install the new seat and reposition the safety belts to ensure that the vehicle continues to co mply with all applicable standards. Instead, the "render inoperative" provision requires your company to carefully compare the installation with the requirements of Standard No. 208 and Standard No. 210, to determine if repositioning the OEM buckle would result in the vehicle no longer complying with either of these standards.

I hope you find this information helpful. If you have further questions, please contact Mary Versailles of my staff at this address or by telephone at (202) 366-2992.

ID: nht90-4.63

TYPE: Interpretation-NHTSA

DATE: November 20, 1990

FROM: Paul Jackson Rice -- Chief Counsel, NHTSA

TO: Wayne Trueman -- Plant Manager BX-100 International

TITLE: None

ATTACHMT: Attached to NHTSA Information sheet entitled Information For New Manufacturers of Motor Vehicles And Motor Vehicle Equipment, dated 9-85 (text omitted); Also attached to letter dated 9-7-90 from W. Trueman to B. Felrice (OCC 5229); Also attache d to drawings of Brake Equalizer, Quick Release Valve, and Relay Valve (graphics omitted)

TEXT:

This responds to your letter asking about requirements for items to be placed in a truck's air brake system. You are particularly interested in requirements that would apply to two new products you are developing. According to your letter, the products will "have the BX-100 Brake Equalizer integrally combined with a Quick Release valve and another with a Relay valve."

By way of background information, the National Highway Traffic Safety Administration (NHTSA) does not provide approvals of motor vehicles or motor vehicle equipment. Under the National Traffic and Motor Vehicle Safety Act, it is the responsibility of th e manufacturer to ensure that its vehicles or equipment comply with all applicable standards. The following represents our opinion based on the facts provided in your letter.

NHTSA does not have any specific regulations covering brake equalizers, quick release valves, or relay valves. However, since these devices are tied into a vehicle's air brake system, they could affect a vehicle's compliance with Federal Motor Vehicle S afety Standard No. 121, Air Brake Systems. That standard applies to almost all new trucks, buses, and trailers equipped with air brake systems.

If one of your devices is installed as original equipment on a new vehicle, the vehicle manufacturer is required to certify that, with the device installed, the vehicle satisfies the requirements of all applicable safety standards. If the device is adde d to a previously certified new motor vehicle prior to its first sale, the person who modifies the vehicle would be required to certify that, as altered, the vehicle continues to comply with all of the safety standards affected by the alteration.

If the device is installed on a used vehicle by a business such as a garage, the installer would not be required to attach a certification label. However, it would have to make sure that it did not knowingly render inoperative, in whole or part, any dev ice or element of design installed on or in a motor vehicle or item of motor vehicle equipment in compliance with an applicable Federal motor vehicle safety standard.

You should also be aware of the requirements of Federal Motor Vehicle Safety Standard No. 106, Brake Hoses, which specifies requirements for motor vehicle brake hose, brake hose assemblies, and brake hose end

fittings. That standard applies to new motor vehicle equipment as well as to new motor vehicles. You should check to see if any parts of your brake devices are subject to the requirements of Standard No. 106.

I am enclosing a copy of an information sheet which identifies relevant Federal statutes and NHTSA standards and regulations affecting motor vehicle and motor vehicle equipment manufacturers. I regret that we are unable to provide information concerning regulations other than those of NHTSA which may apply to your products. You may wish to contact the Federal Highway Administration's Office of Motor Carrier Standards concerning whether any of its regulations are relevant to your products. You may also wish to contact appropriate State authorities, and/or a local attorney, for advice about state and local regulations.

ID: nht90-4.64

TYPE: Interpretation-NHTSA

DATE: November 20, 1990

FROM: M. Iwase -- General Manager, Technical Administration Dept., Koito Manufacturing Co., Ltd.

TO: Paul Jackson Rice -- Chief Counsel, NHTSA

TITLE: Re FMVSS No. 108 (Lamp, reflective devices, and associated equipment) Interpretation and/or Petition for Combination of Headlighting Systems

ATTACHMT: Attached to letter dated 12-13-90 to M. Iwase from Paul Jackson Rice (A36; Std. 108)

TEXT:

We would hereby ask you to provide us with your kind advice to the subject matter.

There are three (3) different kinds of headlighting system as specified in the current FMVSS No. 108 --- Sealed Beam Headlighting System of S7.3, Integral Beam Headlighting System of S7.4 and Bulb Replaceable Headlighting System of S7.5.

We are thinking of taking a new headlamp configuration into our design of headlamps which seems not to come under any of lighting systems abovementioned, as shown in the attached sheet-1.

It is a combination of the current systems, consisting of the integral beam headlighting and the bulb replaceable headlighting, and is a possible and reasonable construction for hybrid headlighting systems combining a new technology of HID headlighting a nd the conventional tungusten filament headlightings, we think. We would hereby ask for your kind advice as to whether the said combination of lighting systems could be accepted in use for the automobile headlamps under the current FMVSS No. 108.

Our intended configuration is just a conbination of lighting systems currently permitted in use, never raising argument on the safety and performance aspect, we believe.

If the configuration is not accepted just because it has not been provided in the wording of the lighting systems of FMVSS No. 108, we would like to petition an amendment of FMVSS No. 108 so that such a configuration as we intend might be accepted to use , by submitting the attached sheet-2 enclosed herewith.

Your kind and favourable attention to this matter would be greatly appreciated.

Attached Sheet 1

Combination of Headlighting Systems

4 Lamp System (Drawing omitted.)

Note:(1) Lower Beam Headlamp is designed to conform to the applicable requirement of S7.5. (2) Upper Beam Headlamp is designed to conform to the applicable requirements of S7.4. (3) Photometric design is in conformity with Fig. 15 of FMVSS No. 108.

2 Lamp System

(Drawing omitted.)

(1) Lower Beam Headlamp is designed to conform to the applicable requirement of S7.5. (2) Upper Beam Headlamp is designed to conform to the applicable requirement of S7.4. (3) Photometric design is in conformity with Fig. 17 of FMVSS No. 108.

Attached Sheet 2

Atten: Mr. Paul Jackson Rice Date: November 20, 1990

Petition for Amendment of FMVSS No. 108 (Lamp, reflective devices, and associated equipment) Combination of Integral Beam and Bulb Replaceable Headlighting System We would hereby petition to amend FMVSS No. 108, as belowmentioned, so that a combination of Integral Beam Headlamp and Bulb Replaceable Headlamp can be use for automobile headlamps;

S7 should be changed as follows;

S7. Each passenger car, multipurpose passenger vehicle, truck and bus shall be equipped with a headlighting system designed to conform to the requierments of S7.3, S7.4 or S7.5. Headlighting systems may be a combination of integral beam headlighting system and bulb replaceable headlighting system provided that each headlamp or part of headlamp meets the applicable requirements. In this case, photometric requirements of Fig. 15 or Fig. 17 shall be met according to the lamp system.

ID: nht90-4.65

TYPE: Interpretation-NHTSA

DATE: November 27, 1990

FROM: Paul Jackson Rice -- Chief Counsel, NHTSA

TO: Cal Karl -- Minnesota State Patrol, District 4700-Commercial Vehicle Section

TITLE: None

ATTACHMT: Attached to letter dated 12-7-82 from F. Berndt to M.B. Mathieson; Also attached to letter dated 1-29-90 from C. Karl to M. Shaw (OCC 4403); Also attached to letter dated 1-18-90 from R.E. Meadows; Also attached to letter dated 1-8-90 from R. Marion to C. Karl; Also attached to letter from C. Karl to All School Bus LCR II's

TEXT:

This is in response to your letter to Marvin Shaw of my staff seeking an interpretation of Standard No. 217, Bus Window Retention and Release (49 CFR S571.217). Specifically, you asked how S5.2.3.2, which applies to school buses, would affect the instal lation of certain designs of "vandal locks" on school buses. I am pleased to have this opportunity to explain this safety standard for you.

Before I address your specific questions, I would like to provide some background information. Throughout this letter, I will use the term "vandal lock" to describe locking systems installed for the doors and emergency exits of school buses intended to prevent unauthorized persons from entering the school bus through those exits when the bus is unoccupied and unattended. S5.2.3.2, the relevant provision of Standard No. 217, reads as follows:

The engine starting system of a school bus shall not operate if any emergency exit is locked from either inside or outside the bus. For purposes of this requirement, "locked" means that the release mechanism cannot be activated by a person at the door w ithout a special device such as a key or special information such as a combination.

Your first question was whether S5.2.3.2 prohibits the use of a vandal lock system that, although it must be unlocked for the bus to start, can be relocked once the bus is started. The answer is that such locks are not prohibited by Standard No. 217. I have enclosed a copy of a December 7, 1982 letter to Mr. M. B. Mathieson in which NHTSA addressed this issue. As stated in that letter, "Nothing in Standard No. 217 prohibits the installation of locking doors (on a school bus) as long as the vehicle can not be started with the (emergency) door in the locked position." In other words, the prohibition in S5.2.3.2 focuses exclusively on whether the vehicle can be started when any emergency exit is locked. If the school bus cannot be started when an emerg ency exit is locked, the bus complies with S5.2.3.2, even if an emergency exit can be locked once the bus is started.

Your second question was whether S5.2.3.2 allows a vandal lock to be relocked after the vehicle is running without the use of a key or special information. The answer to this question is yes. As stated above, the prohibition in S5.2.3.2 focuses exclusi vely on whether the vehicle can be started when any emergency exit is locked. If the school bus cannot be

started when an emergency exit is locked, the bus complies with S5.2.3.2, even if an emergency exit can be locked once the bus is started. Nothing in S5.2.3.2 requires that any locks on emergency exits be relocked only by means of a key or some special information after the vehicle is started.

I appreciate your concern about potential problems that might arise if emergency doors are locked after a school bus is started. Nevertheless, regardless of whether you believe that NHTSA intended to make or should have made some provision to prevent em ergency exits on school buses from being relocked once the bus is started, it is not possible to interpret the language of S5.2.3.2 as including such a provision. Since an interpretation cannot add or delete requirements in the language of a safety stan dard, the only way whereby the standard could include a provision to prevent emergency exits on school buses from being relocked once the bus is started would be for this agency to undertake a rulemaking action to amend the current language of S5.2.3.2.

We are unaware of any safety need to commence such a rulemaking. We do not have any indication that there have been deaths or injuries to school bus occupants as a result of an emergency exit being relocked once the bus was started. Moreover, the poten tial hazards to school bus occupants absent any Standard No. 217 requirements on this subject seem minimal. School bus doors, including emergency doors, should not be locked when the bus is in operation, and we believe that, in practice, they remain unlo cked when the buses are in use. It is also our understanding that the vast majority of school buses with emergency doors that can be locked in this fashion are voluntarily equipped with warning buzzers that alert the driver to the fact that the doors ha ve been relocked.

I hope you find this information helpful. Please do not hesitate to contact David Greenburg of my staff at (202) 366-2992 if you have any further questions or would like some additional information.

ID: nht90-4.66

TYPE: Interpretation-NHTSA

DATE: November 28, 1990

FROM: William A. Batten -- Eaton Corp., Truck Components Operations- North America

TO: Paul Jackson Rice -- Chief Counsel, NHTSA

TITLE: Re FMVSS 124 Accelerator Control Systems

ATTACHMT: Attached to letter dated 3-4-91 from Paul Jackson Rice to William A. Batten (A37; VSA 108(b)(1); VSA 108 (a)(2)(A); Std. 124)

TEXT:

The purpose of this letter is to obtain an interpretation from your office relative to FMVSS No. 124. The question is:

What is the applicable mileage requirement or time domain that a Class 8 Truck (over 10,000 pounds GVWR) must comply with FMVSS No. 124?

I would like to thank you in advance for your consideration in this manner.