ID: 86-6.20

TYPE: INTERPRETATION-NHTSA

DATE: 12/24/86

FROM: AUTHOR UNAVAILABLE; Erika Z. Jones; NHTSA

TO: Tim O. Edwards -- Safety Specialist, Kansas Dept. of Transportation, Bureau of Personnel Services

TITLE: FMVSS INTERPRETATION

TEXT:

Mr. Tim O. Edwards Safety Specialist Kansas Department of Transportation Bureau of Personnel Services 7th Floor, State Office Building Topeka, Kansas 66612

I am writing in response to your recent inquiry concerning interior over-head luggage racks on school buses. Your first question seeks this Agency's opinion on whether interior luggage racks on school buses should be considered "projections likely to cause injury" under the National Minimum Schoolbus Standards. These standards are recommendations by the National Conference on School Transportation (NCST), and are not developed by NHTSA. Requests for interpretation of these Standards should be mailed to the Interpretation Committee, addressed to :

Mr. Norman Loper Coordinator of Pupil Transportation Alabama Department of Education 304 Dexter Avenue Montgomery, AL 36130

Requests for modification to these Standards and development of new Standards should be directed to the chairman of the Interim Committee, addressed to:

Mr. Bill G. Loshbough Asst. State Supt. for Transportation Dept. of Education Education Bldg. Santa Fe, NM 87501-2786

In response to your second question, there are no federal standards or regulations which specifically address the issue of over-head luggage racks on school buses. However, Federal Motor Vehicle Safety Standard No. 222, 49 Code of Federal Regulations (CFR) S571.222 addresses the issue of school bus passenger seating and crash protection. Specifically, S5.3.1 of that standard establishes the head protection zones. As defined in S5.3.1.1, that zone extends up to a horizontal plane 40 inches above the seating reference point. If the luggage rack were to be, located within the head protection zone, the rack would have to meet the head form impact requirement in S5.3.1.2 and the head form force distribution requirement in S5.3.1.3.

Please feel free to contact this office if you have any other questions.

Sincerely,

Erika Z. Jones Chief counsel

Didre Hom, Chief Counsel NHTSA 400 Seventh Street, S. W. Washington, D.C.

Dear Ms. Hom:

In August of this year an inspection was made of a school bus in Caney, Kansas. The Highway Patrol Officer making the inspection determined that the interior over-head luggage racks found on the bus few within the National Minimum (Interior) Standards adopted by Kansas as "a projection likely to cause injury".

This has raised the question of how to handle similar luggage racks on other buses. We would request your agencies opinion on the following questions:

1. Is an interior luggage rack "a projection likely to cause injury?

2. Are there any federal standards, regulations, etc., which would specifically address this problem?

Thank you for your assistance in this matter. Please address your response to:

Kansas Department of Transportation ATTN: Tim O. Edwards, Safety Specialist Bureau of Personnel Services 7th Floor, State Office Building Topeka, Kansas 66612

Sincerely

CONNIE HAFENSTINE, CHIEF BUREAU OF PERSONNEL SERVICES

TIM O. EDWARDS SAFETY SPECIALIST II

ID: nht89-1.75

TYPE: INTERPRETATION-NHTSA

DATE: 04/17/89

FROM: ERIKA Z. JONES -- CHIEF COUNSEL NHTSA

TO: LEON E. PANETTA -- HOUSE OF REPRESENTATIVES

TITLE: NONE

ATTACHMT: LETTER DATED 02/04/89 FROM LEON E., PANETTA TO ERIKA Z. JONES

TEXT: Dear Mr. Panetta:

This letter responds to your inquiry on behalf of your constituent, Mr. Botelho. You asked whether Federal regulations require mirrors to be placed on the right side of vehicles and whether such mirrors must be convex in nature. Mr. Botelho expressed hi s objection to requiring convex mirrors, because he believes convex mirrors distort images and cause objects to appear further away than they actually are. I am pleased to have this opportunity to explain this requirement and its background for you.

Standard No. 111, Rearview Mirrors (49 CFR @ 571.111, copy enclosed)) establishes performance and location requirements for the rearview mirrors installed in new vehicles. Specifically, a passenger car whose inside rearview mirror does not meet the fiel d of view requirements of section S5.1.1 must have an outside mirror on the passenger side of either unit magnification of a convex mirror. In a September 2, 1982 final rule amending Standard No. 111, the National Highway Traffic Safety Administration ( NHTSA) explained that convex mirrors offer safety benefits by providing an expanded field of view to the rear, thereby reducing the need for the driver to turn around to view the rear directly. On the other hand, some users of convex mirrors that were u sed to the images shown by conventional plane mirrors incorrectly perceived that the object shown in the convex mirror was further to the rear than it actually was. Additionally, some users of convex mirrors experienced double vision, eyestrain, and naus ea. After considering these potential advantages and disadvantages, NHTSA amended Standard No. 111 so that it does not require any vehicle to be equipped with convex mirrors, but it permits the use of convex mirrors on the passenger side of cars and lig ht trucks, provided that the convex mirror meets certain additional requirements.

The additional requirements applicable to convex mirrors on the passenger side of cars and light trucks are:

1. A maximum radius of curvature for the convex mirror. This limits the range of convexities to which drivers will be exposed. It also

ensures that the field of view will be noticeably greater than for a plane mirror.

2. A minimum radius of curvature for the convex mirror. This ensures that the image size in the convex mirror will be adequate and distortion will not be excessive.

3. A stringent maximum permissible variation in the radius of curvature over the surface of the convex mirror. This requirement, which is more stringent than the European requirement in this area, also ensures that convex mirrors will have low distortio n.

4. A warning etched on the convex mirror that objects shown in the mirror are closer than they appear. This requirement ensures that the driver who may not be familiar with convex mirrors will not be misled by the image size of the convex mirror and the apparent distance to the object.

Hence, we agree with Mr. Botelho that the area he has identified are potential problems unique to convex mirrors. However, our standard includes special requirements for convex mirrors to minimize the potential problems identified by Mr. Botelho and oth er potential problems that were identified in research studies of convex mirrors. We are not aware of any data showing that convex mirrors that comply with those special requirements present any unacceptable problems for drivers.

I hope this information is helpful. If you have any further questions or need any additional information on this subject, please let me know.

Sincerely,

ENCLOSURE

ID: nht88-2.34

TYPE: INTERPRETATION-NHTSA

DATE: 05/27/88

FROM: TEVES, ALFRED -- TEVES TECHNICAL SERVICE

TO: ERIKA Z. JONES -- NHTSA CHIEF COUNSEL

TITLE: BRAKE FLUID RESERVOIR DESIGN ACCORDING TO FMVSS 105 REQUEST FOR INTERPRETATION

ATTACHMT: OCTOBER 9, 1981 LETTER FROM BERNDT TO KAWANO, OCTOBER 3, 1988 LETTER FROM JONES TO BURKARD, EBNER, AND TEVES, FEBRUARY 3, 1981 LETTER FROM KAWANO TO BERNDT, JULY 10, 1974 LETTER FROM DYSON TO NAKAJIMA, AND MAY 24, 1988 LETTER FROM TEVES TO GREG ORY

TEXT: during his visit at NHTSA on May 17th, 1988 Mr. Ebner presented our new brake system to your experts.

We request an interpretation of S 5.4.2 (reservoir capacity) and S 5.3.1/b (Fluid level indicator) of FMVSS 105, with respect to the proposed brake fluid reservoir shown in the attachment.

Essential is the existence of an ancillary brake unit in this new brake system. This ancillary brake unit serves the brake circuits 1 and 2 directly.

Compared with a conventional reservoir the proposed brake fluid reservoir's distinctive feature is the exit for the ancillary unit.

This ancillary unit serves the brake circuits 1 and 2. When the brake pedal is released, the used brake fluid will flow back to the reservoir. This unit does not cause any additional fluid volume.

Teves interprets standard 105 S 5.4.2 and S 5.3.1/b) as follows:

1. The total minimum capacity of a reservoir shall be equivalent to the fluid displacement resulting when all the wheel cylinder or caliper pistons serviced by the reservoir move from a new lining, fully retracted position to a fully worn, fully applied position.

2. Reservoir systems utilizing a portion of the reservoir for a common supply to two or more subsystems, individual partial compartments shall each have a minimum volume of fluid equal to at least the volume displaced by the master cylinder piston servi cing the subsystem, during a full stroke of the piston.

3. The total amount of the fluid shall be solely available for the brakes.

4. The ancillary unit shall not use brake fluid for other purposes than for the brake circuits.

5. A drop in the level of brake fluid in any master cylinder reservoir compartment to less then the recommended safe level specified by the manufacturer ot to one-fourth of the fluid capacity of that reservoir compartment, which ever is greater.

The ancillary unit does not diminish the built in safety features of the reservoir. In case of a circuit failure, volume 1 resp. volume 2 remains still available for the brakes and the fluid level indicator lamp gives a warning to the driver.

In case of a fluid leakage in the ancillary unit, the unit is switched off. The fluid level indicator lamp and additional a separate warning lamp gives a warning to the driver. The fluid volumes 1 and 2 remain in the reservoir and are fully usable fo r applying the brakes with the master cylinder.

Accordingly, we believe that the proposed brake fluid reservoir described in this letter and presented to your experts fulfils the requirements S 5.4.2 and S 5.3.1 (b) of FMVSS 105.

We ask that you confirm our interpretation at your earliest convenience.

FMVSS 105, S 5.4.2: V = V[1] + V[2] + V[3] + V[4] V: GREATER OR EQUIVALENT TO FLUID DISPLACEMENT RESULTING WHEN ALL W/C MOVE FROM A NEW LINING POSITION TO A FULLY WORN LINING POSITION. MAX V[4] FLI V[3] V[1] V[2] BRAKE BRAKE ANCILLARY UNIT CIRCUIT 1 CIRCUIT 2 SERVICING BRAKE CIRCUIT 1+2

FMVSS 105, S 5.3.lb V[1] + V[3] >/- 0.25 (V[1] + V[3] + V[4]) V[2] + V[3] >/- 0.25 (V[2] + V[3] + V[4])

V[1] VOL. DISPLACEMENT EQUIVALENT TO A V[2] >/- FULL STROKE OF THE RELATED M/C-PISTON. TEVES MASTER CYLINDER RESERVOIR DESIGN ACCORDING TO FMVSS 105 3-34513-07

ID: 22137(2)

Bob Snyder, Vice President
Longacre and Associates, Inc.
424 Fourth Street
Suite C
Annapolis, MD 21403


Dear Mr. Snyder:



This responds to your August 24, 2000, letter asking whether vehicles are allowed to have any size side windows in the front seat occupant compartment. Specifically, you ask about the requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 205, Glazing materials (49 CFR 571.205) and FMVSS No. 214, Side door strength (49 CFR 571.214), as applied to a flatbed-type truck with a gross vehicle weight rating of 18,000 pounds. Our answer is that our standards do not directly limit the size of vehicle side windows.

By way of background information, the National Highway Traffic Safety Administration (NHTSA) has the authority to issue FMVSSs applicable to new motor vehicles and new items of motor vehicle equipment. Federal law establishes a self-certification system under which motor vehicle and equipment manufacturers themselves certify that their products comply with all applicable standards. For that reason, NHTSA neither tests, approves, disapproves, nor endorses products prior to their introduction into the retail market. Rather, we enforce compliance with the standards by purchasing new vehicles and equipment and testing them. We also investigate safety-related defects.

Our FMVSSs set forth requirements for safety performance, in terms that minimize design restrictions. Ejection of occupants through glazing (through windshields or the side windows) is a safety concern addressed by several standards, including FMVSS No. 205. FMVSS No. 205 sets performance requirements for glazing materials used in new motor vehicles and glazing materials sold as items of replacement equipment. FMVSS No. 212, Windshield mounting (49 CFR 571.212), establishes windshield retention requirements to reduce the likelihood of ejection of occupants in a crash. FMVSS No. 217, Bus emergency exits and window retention and release (49 CFR 571.217), establishes requirements for the retention of windows in buses, to minimize the likelihood of occupants being thrown from the bus.

You also inquire about the requirements of FMVSS No. 214. FMVSS No. 214 specifies vehicle crashworthiness requirements in terms of accelerations measured on anthropomorphic dummies in test crashes and specified strength requirements for side doors. FMVSS No. 214 does not apply to trucks with a gross vehicle weight rating of 18,000 pounds.

At this time, the above-discussed standards do not directly restrict the size of side windows. NHTSA, however, in response to the NHTSA Authorization Act of 1991 and ongoing research into rollover and ejection mitigation, is currently evaluating the potential of advanced glazing systems to reduce occupant ejection. The agency has recently published a report entitled "Ejection Mitigation Using Advanced Glazing: Status Report II" which evaluates the progress of that advanced glazing research. This report is available online at http://www-nrd.nhtsa.dot.gov/include/nrd10/nrd11/glazing.html or may be ordered through NHTSA's Technical Information Services at 1-800-445-0197.

I note that the Department's Federal Motor Carrier Safety Administration (FMCSA) has jurisdiction over interstate motor carriers operating in the United States. FMCSA was established on January 1, 2000, and was formerly a part of the Federal Highway Administration (FHWA). You may wish to contact the FMCSA at (202) 366-4012 for information concerning the issues discussed in your correspondence.

I hope this information is helpful. If you have any questions or need additional information, feel free to contact Nancy Bell of my staff at (202) 366-2992.

Sincerely,

Frank Seales, Jr.
Chief Counsel

ref:205
d.1/3/01

ID: 1985-04.7

TYPE: INTERPRETATION-NHTSA

DATE: 10/27/85

FROM: AUTHOR UNAVAILABLE; Jeffrey R. Miller; NHTSA

TO: Lawrence F. Henneberger, Esq. -- Arent, Fox, Kintner, Platkin and Kahn

TITLE: FMVSS INTERPRETATION

TEXT:

Lawrence F. Henneberger, Esq. Arent, Fox, Kintner, Plotkin & Kahn Washington Square 1050 Connecticut Avenue, N.W. Washington, D.C. 20036-5339

Thank you for your letter of September 16, 1985, concerning the applicability of the requirement in Federal Motor Vehicle Safety Standard No. 108 for the installation of center high-mounted stop lamps (CHMSL's) to passenger cars manufactured before September 1, 1985. You also asked about the applicability of the CHMSL performance requirements to CHMSL's sold as aftermarket equipment for cars manufactured before that date. I hope the following discussion answers your questions.

You are correct in stating that there is no requirement in Standard No. 108 for installing CHMSL's on new cars manufactured before September 1, 1985. The installation requirement applies only to cars manufactured on or after that date. (48 FR 48235, October 13, 1984.) The only requirements regarding CHMSL's and pre-September 1, 1985 cars are that if a manufacturer voluntarily installs a CHMSL on a car manufactured on or after August 1, 1984, and before September 1, 1985, the installation must be performed in accordance with criteria concerning the location of the CHMSL, and reflections from it. (49 FR 34488, August 31, 1984.)

As to aftermarket CHMSL's for cars manufactured before September 1, 1985, the applicability depends on whether or not the CHMSL is intended to be installed as a replacement for an original equipment CHMSL that was voluntarily installed on a car that was manufactured on or after August 1, 1984, but before September 1, 1985. If the aftermarket CHMSL is intended to be installed in the interior of such a car, then the manufacturer of the CHMSL must comply with the requirement in S3.1.8.4 concerning minimization of reflections. If the CHMSL is intended to be installed on other pre-September 1, 1985 cars, its manufacturer is not subject to any Standard No. 108 requirements for CHMSL's. However, the agency encourages manufacturers of any aftermarket CHMSL to conform as closely as possible to all criteria in the standard for original equipment CHMSL's. We believe that standardization of rear signals minimizes the possibility of creating confusion to following drivers in situations where immediate action is essential to avoid a rear end collision. Further, aftermarket CHMSL's for those other pre-September 1, 1985 cars would be regulated by the applicable law of the State in which they are operated.

I hope this information is of assistance to you. If you have further questions, please let me know.

Sincerely, Jeffrey R. Miller Chief Counsel (202) 857-6087

September 16, 1985 Jeffrey R. Miller, Esquire Chief Counsel National Highway Traffic Safety Administration 400 Seventh Street, S.W., Room 5219 Washington, D.C. 20590 Re: Request for Interpretation; FMVSS 108

Dear Mr. Miller:

As we discussed by telephone, I am requesting that you confirm that Federal Motor Vehicle Safety Standard 108, as it relates to the requirement for installation of a single center, high-mounted stoplamp on passenger cars, does not apply to passenger cars manufactured prior to September 1, 1985, and therefore does not apply to aftermarket center high-mounted stoplamps produced for applications on passenger cars manufactured prior to September 1, 1985.

An expedited response will be very much appreciated.

Sincerely, Lawrence F. Henneberger

ID: 20264.drn

Russell Roden, P.E.
President
Atlantic Design Inc.
3740 Federal Lane
Abingdon, MD 21009-2742

Dear Mr. Roden:

This responds to your request for an interpretation whether your products are "motor vehicles" within the National Highway Traffic Safety Administration's (NHTSA's) definition. As explained below, the answer is no.

Your letter states that your company designs and manufactures "modular process systems" for the construction, industrial maintenance, and the quarry and mining industry. Your products include grit recycling and dust collection systems, and sand "dedusting units." In order to facilitate movement, your company's equipment is permanently attached to flat trailers which are manufactured by another company. You emphasize that the equipment your company designs and manufactures is a "process system where the trailer is used as a base skid with wheels for mobility and erection." As an example of your company's products, you included a photograph of an "air classification system" used in the bridge and industrial painting industry and in the quarry and mining industry.

In a telephone conversation with Dorothy Nakama of my staff, you explained that the length of time your company's equipment is at a job site depends on the task. The equipment could be at a maintenance or construction site or at a quarry for years at a time. You stated that the equipment rarely stays at a job site for less than six to eight weeks.

NHTSA's statute defines "motor vehicle" at 49 U.S.C. 30102(a)(6) as:

a vehicle driven or drawn by mechanical power and manufactured primarily for use on public streets, roads, and highways, but does not include a vehicle operated only on a rail line.

Whether the agency considers your products to be motor vehicles depends on their use. The statutory definition does not encompass mobile construction equipment, such as cranes and scrapers, which use the highway only to move between job sites and which typically spend extended periods of time at a single job site. In such cases, the on-highway use of the vehicle is merely incidental and is not the primary purpose for which the vehicle was manufactured. In contrast are instances where vehicles, such as dump trucks, frequently use the highway going to and from job sites, and stay at a job site for only a limited time. Such vehicles are considered motor vehicles for purposes of our statute, since the on-highway use is more than "incidental."

Based on your description, it appears that your company's vehicles are not motor vehicles within the meaning of our statute. This is because the vehicles stay on job sites for extended periods of time (usually for months or years) and only use the highway to move from site to site. We may reassess this interpretation if we were to receive additional information indicating that your vehicles use the roads more than on an incidental basis.

Please note that since States may require products such as those which your company manufactures to be registered, you may wish to contact State motor vehicle administrators to determine whether there are State requirements you must meet.

You also pose several questions about the application of excise taxes to your product. We are unable to answer questions relating to taxes. For further information about Federal taxes, please contact the U.S. Internal Revenue Service (IRS). The IRS's web site is at www.irs.gov. You should contact the State of Maryland for information about Maryland tax law.

I hope this information is helpful. If you have any questions, please contact Dorothy Nakama at (202) 366-2992.

Sincerely,
Frank Seales, Jr.
Chief Counsel
ref:VSA
d.10/26/99

ID: nht79-2.17

DATE: 03/19/79

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Rolls-Royce Motors

TITLE: FMVSS INTERPRETATION

TEXT:

FMVSS INTERPRETATION Mar 19 1979

Mr. J. B. H. Knight Chief Car Safety Engineer Rolls-Royce Motors Crewe Chesire CW1 3PL England

Dear Mr. Knight:

This responds to your letters of July 11, 1978, and January 18, 1979, concerning Federal Motor Vehicle Safety Standard (FMVSS) 101-80, Controls and Displays. I regret the delay in responding to your inquiry. The answers to your questions are as follows:

1. The turn signal control lever used by Rolls-Royce is mounted on the steering column and is positioned horizontally. To operate the turn signals, the lever must be rotated either clock-wise or anti-clock-wise. To label the control lever and to indicate the manner of operation, Rolls-Royce is considering placing the arrows of the turn signal symbol so that they point up and down. You ask whether the standard permits that orientation of the arrows.

The answer is no. Section 5.2.1 requires that the turn signal symbol appear perceptually upright to the driver. The upright position of a symbol is determined by referring to column 3 of Table 1 of the standard. That table shows that the upright position for the turn signal symbol is with the arrows pointing horizontally. Thus, the arrows must point essentially horizontally in the motor vehicle. Complying with the perceptually upright requirement instead of reorienting the symbol to serve other purposes will aid in ensuring quick and accurate identification of the turn signal control. We wish to observe that essentially the same result as that sought by RollsRoyce in reorienting the turn signal symbol could be achieved by placing curved, thinner arrows next to the symbol to indicate mode of operation.

2. (i) You noted that differing display identification requirement for safety belts appear in FMVSS 101-80 and FMVSSS 208. FMVSS 101-80 does not supersede or preempt FMVSS 208 in this area. However, the agency will soon issue a notice that will provide for use of the safety belt symbol in Table 2 of FMVSS 101-80 for the purposes of both standards.

(ii) You are correct in assuming that column 3 of Table 2 should include a reference to FMVSS 105-75 for brake system malfunction displays and a reference to FMVSS 121 for brake air pressure displays. These inadvertent omissions will be corrected in the notice mentioned above. You are also correct in assuming that the options in section 5.3.5 of FMVSS 105-75 are still available.

3. You referred to the statement in the final rule preamble that the visibiiity requirements of 101-80 would be deemed satisfied even if minimal movements by the driver were necessary and suggested that this interpretation be incorporated in section 6, conditions, and amplified. The agency does not believe that this step is necessary. The agency does, however, believe it appropriate to amplify its earlier interpretation. By minimal movement, the agency meant head movement of not more than a few inches. By a "few" inches, we mean up to approximately thee inches. As to your suggestion for specifying the size of the driver to be used in determining compliance with the visibility requirements, the acency will consider this suggestion and address it at a future date.

4. You should comply with the speedometer scale requirements in FMCSS 101-80 since the labelling requirements in FMVSS 127 were deleted in the response to reconsideration petitions that was published July 27, 1978 (43 FR 32421).

Sincerely,

Frank Berndt Acting Chief Counsel

NOA-30:KDeMeter:pfp:3/5/79 cc: NOA-30 Subj/Chvon NOA-30 Ms. DeMeter NRMS-11 Interps: Std. 101-80 Redbook: (3) CC

ID: nht74-4.32

DATE: 07/03/74

FROM: AUTHOR UNAVAILABLE; R. L. Carter; NHTSA

TO: Alfred Teves GMBH

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your May 10, 1974, request for permission to stamp label information on hose assemblies in place of banding, and to reduce S9.2.5 burst pressure from 350 to 100 psi, and your further request for an interpretation of the status of an in-line check valve as part of a vacuum brake hose.

The in-line check valve is not subject to Standard No. 106, Brake hoses, as a brake hose and fitting. In this configuration, the couplers depicted in your drawing are the clamps, and the check valve is a separate component to which the hose assemblies are attached.

The issue of stamping instead of banding will be answered in our upcoming Notice 11 in response to petitions for reconsideration of the brake hose standard.

Your petition for a reduction in the burst strength requirement for vacuum hoses is denied. The minimum burst pressure of 350 psi was established by the Society of Automotive Engineers in 1942, taking into consideration the effects of backfire pressure and the severe underhood environment to which vacuum hose may be exposed. Hoses with this burst pressure have provided excellent reliability and durability. We have no data to justify a reduction in burst strength in view of the two hazards just cited.

MAY 10, 1974

National Highway Traffic Safety Administration US Department of Transportation

Subject: Motor Vehicle Safety Standard No. 106

(Docket no. 1-5, Notice 10

According to Notice 10 the designation of fittings was dropped due to objections raised by various manufactures because of insufficient clearness. For years we successfully used to emboss the date of manufacture on to the fittings (after the swaging process). We therefore ask you to extend item S 5.2.4 to the effect that in case of two-piece end fittings, which are attached by crimping or swaging, embossing of the designation on to the fittings will also be allowed instead of using a band.

The present standard according to which only a band will be allowed would be connected with a high degree of capital expenditure (reconstruction of entire assembly machinery) for the manufacturing department of Alfred Teves GmbH.

As far as vacuum brake hoses (see item S 9.2.5) are concerned, we think that a 350 psi burst strength is too high. The maximum operating pressure amounts to a vacuum of 0,80 bar, so that the required 350 psi would mean a 27-fold safety.

For this field of application a burst strength of 100 psi is sufficient. We therefore ask you to amend item S 9.2.5 to the effect that in the case of vacuum brake tubes the burst strength will be reduced to 100 psi.

Our production programm also comprises a vacuum check valve, which 1st mounted between two vacuum brake tubes, according to the attached sketch. We kindly ask you to inform us whether in the case of vacuum check valves the same requirements as are applicable for complete brake tubes regarding a burst strength of 350 psi (item S 9.2.5) and a minimum cross-section of 70% (item S 9.2.1) will be made.

Considering the near effective date of FMVSS, we would like to receive your answer concerning the three items mentioned above as soon as possible.

Yours sincerely

ALFRED TEVES GMBH

ppa.

i.V.

BELLER

Attachment

1 sketch

Ruckschiagventil

Schlauchhalter

Vakuumschiauch

(Graphics omitted)

ID: nht81-1.9

DATE: FEBRUARY 3, 1981

FROM: J. KAWANO -- GENERAL MANAGER, U.S. REPRESENTATIVE OFFICE-TOYOTA

TO: FRANK BERNDT -- NHTSA CHIEF COUNSEL

TITLE: INTERPRETATION OF FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 105-75

ATTACHMT: OCTOBER 3, 1988 LETTER FROM JONES TO BURKARD, EBNER, AND TEVES, OCTOBER 9, 1981 LETTER FROM BERNDT TO KAWANO, JULY 10, 1974 LETTER FROM DYSON TO NAKAJIMA, MAY 24, 1974 LETTER FROM TEVES TO GREGORY, AND MAY 27, 1988 LETTER FROM TEVES TO JONES

TEXT: Toyota is currently considering a new type of brake reservoir, as shown in Fig. 1, in accordance with your letter enclosed herewith as Attachment #1.

We request clarification of our interpretation of @5.4.2 & 5.3.1 of FMVSS No. 105-75, concerning this type of brake reservoir.

S5.4.2 reads as follows:

Reservoirs, whether for master cylinders or for other type systems, shall have a total minimum capacity equivalent to the fluid displacement resulting when all the wheel cylinders or caliper pistons serviced by the reservoirs move from a new lining, fully retracted position (as adjusted initially to the manufacturer's recommended setting) to a fully worn, fully applied position, as determined in accordance with S7.18(c) of this standard. Reservoirs shall have completely separate compartments for each subsystem except that in reservoir systems utilizing a portion of the reservoir for a common supply to two or more subsystems, individual partial compartments shall each have a minimum volume of fluid equal to at least the volume displaced by the master cylinder piston servicing the subsystem, during a full stroke of the piston.

As far as our new type of brake reservoir is concerned, we recognize that if the following three conditions were satisfied, these reservoirs would conform to S5.4.2. Is this interpretation correct?

i) W + X + Y > C + D + E *

ii) X > A

iii) Y > B

* (Note: A vehicle equipped with this type of reservoir can be expressed as W+X+Y>C+D, since E is equivalent to zero.)

W; common capacity for fluid of front brake, rear brake & clutch as hatching part in Fig. 1

X; a compartment capacity for front brake fluid Y; a compartment capacity for rear brake fluid

A; volume displaced by front master cylinder during a full stroke of position

B; volume displaced by rear master cylinder during a full stroke of position

C; front capacity of fluid when all cylinder pistons serviced by the reservoirs from a new lining, fully retracted position to fully worn, fully applied position

D; rear capacity of fluid when all cylinder pistons serviced by the reservoirs from a new lining, fully retracted position to fully worn, fully applied position

E; clutch capacity of fluid when all cylinder pistons serviced by the reservoirs from a new lining, fully retracted position to fully worn, fully applied position

In accordance with the aforementioned interpretation, we recognize that if the warning level is not less than the level of 1/4 (W+X+Y), S5.3.1 would be satisfied. This "W" is the same volume as the "W" in expression i) of inequality. Is this interpretation correct? The main point in question is whether the "W" in expression i) of inequality can be considered the capacity in a case where the overall compartment system -- clutch included -- has not failed. We illustrate such a case in te hatching segment of Fig. 1.

We would appreciate a reply at your earliest convenience. If you should have any comments or questions, please contact Mr. M. Mori, a member of my staff, who can be reached at: (201) 865-2019. Thank you.

Enclosure.

Fig. 1. Warning level.

ID: 2878o

Mr. Michael Rose
Technical Secretary for Executive Director
Jamaica Bureau of Standards
6 Winchester Road
Kingston l0
JAMAICA

Dear Mr. Rose:

This responds to your letter, addressed to the Director of the Office of the Federal Register, concerning Federal Motor Vehicle Safety Standard No. l09, New Pneumatic Tires. The National Highway Traffic Safety Administration (NHTSA) is the Federal agency which issued and administers that standard. Your questions are addressed below.

By way of background information, NHTSA issues Federal motor vehicle safety standards under the National Traffic and Motor Vehicle Safety Act, l5 U.S.C. l38l et seq. The term "motor vehicle safety standard" is defined by the Act as "a minimum standard for motor vehicle performance, or motor vehicle equipment performance, which is practicable, which meets the need for motor vehicle safety and which provides objective criteria" (section l02(2)). NHTSA does not grant approvals of motor vehicles or motor vehicle equipment. Instead, section ll4 of the Act requires manufacturers to certify compliance of each motor vehicle and item of equipment with all applicable standards. The Act requires that manufacturers exercise "due care" to ensure that their products conform to each applicable standard (section l08(b)(l)).

I will address your first two questions together. The questions are:

l. In the clause dealing with Test Sample, why are the batch size and sample size not mentioned?

2. Why does the standard make no reference to the frequency of testing.

As indicated above, Standard No. l09 is a minimum performance standard. All tires must be capable of meeting the standard's requirements.

The purpose of the test sample paragraph (S4.2.2.l) in Standard No. l09 is to indicate that a test set for a compliance test consists of three tires. One tire is checked for physical dimensions and is then subjected to resistance to bead unseating and strength, in sequence. The second tire is subjected to the endurance test, and the third tire is subjected to the high speed test.

Paragraph S4.2.2.l is not intended to address the question of how many sets of tires a manufacturer should test as a surveillance procedure during production or what batch size the test sets should be drawn from. A manufacturer is not required to conduct any particular frequency of testing or even to run the actual tests specified by Standard No. l09. Instead, a manufacturer must take whatever steps are necessary to ensure that each of its tires, if tested according to the requirements of the standard, would meet those requirements. (For test purposes, however, any one given tire would only be subjected to one of the three test sequences discussed above.) Since Standard No. l09 includes a number of specific test requirements, it is likely that a manufacturer would find it necessary to do some testing in order to ensure that a tire complied with the standard. For enforcement purposes, NHTSA would test a tire according to the specific test requirements of Standard No. l09.

Your third question is as follows:

3. Why does the standard make no reference to tolerances for tyre concentricity?

NHTSA's standards cover aspects of performance for which the agency has determined there is a safety need. To date, NHTSA has not determined that there is a need for requirements covering tire concentricity tolerances. We note that tire concentricity appears to be primarily an issue of occupant comfort rather than safety.

I hope this information is helpful.

Sincerely,

Erika Z. Jones Chief Counsel

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