ID: nht76-2.36

DATE: 11/22/76

FROM: AUTHOR UNAVAILABLE; E. T. Driver; NHTSA

TO: TYM Industries Co., Ltd.

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of September 27, 1976, to the National Highway Traffic Safety Administration, concerning lighting requirements for mopeds.

The headlamp must be designed to conform to SAE Standard J584, "Motorcycle and Motor Driven Cycle Headlamps," April 1964. This Standard does not require a sealed beam headlamp, nor is a minimum wattage specified. Obtaining an AAMVA certificate is probably the best way of insuring that a State raises no obstacles to registry of your vehicle.

There is no minimum wattage for the taillamp or stop lamp. These two lamps may be combined. There is no Federal requirement for SAE identification; however, most lamps are so identified, because of the requirements in the state of Virginia.

ID: nht91-6.4

DATE: September 18, 1991

FROM: Robert A. Nordmeyer -- Nordic Associates

TO: NHTSA Administrator, Rule Making Department

TITLE: None

ATTACHMT: Attached to letter dated 11-13-91 from Paul Jackson Rice to Robert A. Nordmeyer (A38; Std. 201; Std. 302)

TEXT:

We are developing an after market sun visor for a client (illustrations attached).

Would you please advise me if there are any federal sanctions governing the design, maximum viewing area that may be blocked by such a device, minimum force required to secure the visor in the extended or retracted position and minimum amount of padding on edges of the visor.

If you have any questions regarding this issue, I can be reached by phone at (818) 347-1597 or Fax (818) 883-3342.

ATTACHMENT

Six drawings of sun visors. (Graphics omitted)

ID: nht81-3.38

DATE: 11/12/81

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Cosco

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your letter concerning the application of Standard No. 213, Child Restraint Systems, to a booster seat that uses a vehicle lap belt or lap/shoulder belt to restraint a child weighing 20 or more pounds. The following discussion answers your questions concerning the application of specific sections of the standard to a booster seat.

Section 4 of the standard 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 pounds." Since the booster seat you described would be used to seat a child weighing less than 50 pounds in a vehicle, it is a child restraint system and thus must meet the requirements of the standard. The vehicle lap belt (Type I belt) or lap/shoulder belt (Type II belt) used with the system are specifically excluded by the definition of child restraint system and thus are not covered by the requirements of the standard.

You said that the booster seat would have no sides, back or fixed or movable surface directly in front of the child and asked how the standard would apply to such a design. The standard does not require a child restraint to have a back, sides or fixed or movable surface in front of the child. If such surfaces are provided, however, they must comply with the applicable requirements of sections 5.2.2, 5.2.3, and 5.2.4.

Each child restraint is required to meet the minimum head support surface requirements of S5.2.1. Section 5.2.1.2, however, exempts forward-facing child restraint from the minimum head support surface requirement if, "the target point on either side of the dummy's head is below a horizontal plane tangent to the top of the standard seat assembly when the dummy is positioned in the system and the system is installed on the assembly in accordance with S6.1.2." Thus, unless your design is within the exception of S5.2.1.2, it would have to comply with the minimum head support requirements of S5.2.1.1. Any head support surface would also have to comply with the applicable requirements of S5.2.3. and S5.2.4.

You asked about the application of S5.4.3.2 to a booster seat. Section 5.4.3.2 provides that:

Each belt that is a part of a child restraint system and that is designed to restrain a child using the system and to attach the system to the vehicle shall, when tested in accordance with S6.1, impose no loads on the child that result from the mass of the system or the mass of the seat back of the standard seat assembly specified in S7.3. (Emphasis added.)

As previously mentioned, the definition of a "child restraint system" specifically excludes Type I or Type II seat belts from the coverage of the standard. Thus, under that definition and the language emphasized above, the requirements of S5.4.3.2 do not apply to the lap and lap/shoulder belts used with a child restraint system. The agency, however, is concerned that when a vehicle lap belt is used with a child restraint system to restrain a child that the lap belt be positioned so that it does not apply impact loads to the abdomen of the child, the area most vulnerable 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 and thighs of a child, areas of the body best able to withstand the forces imposed by the vehicle belt. Based on the drawing of your restraint, we are concerned that the vehicle lap belt may not be properly positioned and securely held by the restraint. Instead, the lap belt may allow submarining and may apply impact loads to the abdomen. The agency is also concerned that the lap belt should be properly positioned and securely held so that no substantial inertial loads of the booster seat are applied to the child.

You stated that the booster seat would not have a harness system when it is used at a vehicle seating position equipped with a lap/shoulder belt. The standard does not require the use of a harness in a child restraint system. Section 5.4.3.3 of the standard provides, in part, that "each child restraint system . . . that has belts designed to restrain the child" must comply with the specific requirements of S5.4.3.3. (Emphasis added.) Thus, the specific requirements of S5.4.3.3 on harness systems only applies if a manufacturer provides belts as a part of the system.

Finally, you said that the booster seat would be sold with an auxiliary tethered shoulder harness. The harness would attach to the vehicle lap belt when the booster seat is used at a vehicle seating position that has no lap/shoulder belt. The harness would not have a crotch strap. As discussed previously, section 5.4.3.3 of the standard specifies the requirements that a child restraint system which provides a belt system must meet. S5.4.3.3(c) provides:

(c) In the case of each seating system recommended for children over 20 pounds, crotch restraint in the form of:

i) a crotch strap connectable to the lap belt or other device used to restrain the lower torso, or

ii) a fixed or movable surface that complies with S5.2.2.1(c).

The purpose of subsection (c) is to require a belt or surface design that will prevent the child from submarining under the lap belt (i.e., sliding down and forward under the belt). Thus, if a crotch belt is not provided, the surface of the restraint must be designed to prevent submarining and comply with S5.2.2.1(c). For example, the seating surface of the restraint could be designed to prevent submarining.

If you have any further questions, please let me know.

SINCERELY,

COSCO

Frank Berndt, Chief Counsel U.S. Dept. of Transportation National Highway Traffic Safety Administration July 27, 1981

Dear Mr. Berndt:

We are in the process of evaluating various new concepts for future child restraints we may produce. In this evaluation, we are uncertain what will or will not be allowed under the 213-80 juvenile car seat standard on designs that have a minimal "booster" seat and rely on the automobile adult lap belt or the auto adult lap/shoulder belt as a direct means of restraining the child.

If we had a design that was specified to be used only by children over 20 lbs., that had a firm seating platform with no sides or back, that by its design properly positioned the auto's three (3) point adult lap/shoulder belt for this age of child to provide adequate protection during dynamic testing, would such a design be allowed by the 213-80 juvenile car seat standard? It should be noted that the auto belts would be in direct contact with the child; there would be no other harness belts when used in an auto seat that provides a lap/shoulder belt; there would be no crotch strap at any time, but there would be an auxiliary tethered shoulder harness that would attach to the auto lap belt for use where no automobile lap/shoulder belt is provided. Finally, there would be no fixed or movable surface directly forward of the child. A drawing representing this concept is attached.

There are several sections of the standard that need interpreting on how they relate to such a design. They include Sections S5.4.3.2. through to Section S5.5 and others.

Would you please give us your official interpretation on whether this proposed design would comply with the 213-80 standard? We hope you will be able to give these questions your immediate attention.

Roy Knoedler Senior Industrial Designer

ENC.

(Graphics omitted)

ID: 24157.ztv

Robert G. Mills, Supervisor, Homologation
Triumph Motorcycles, Ltd.
Jacknell Road
Hinckley, Leicestershire LE10 3BS
United Kingdom

Dear Mr. Mills:

This is in reply to your fax of March 14, 2002, asking three questions with respect to Federal Motor Vehicle Safety Standard No. 108, Lamps, Reflective Devices, and Associated Equipment (FMVSS No. 108). Pursuant to our request, you provided supplemental information on April 17, 2002.

Your questions are:

"1. If an SAE recommended practice that is referenced in FMVSS 108 is revised and updated by SAE, is the latest revision . . . automatically adopted in FMVSS 108? If not, does an earlier dated version remain in the regulation?

SAE materials that are referenced and subreferenced in FMVSS No. 108 are not automatically updated when the SAE revises them, and "earlier dated versions" remain in effect. That is because an SAE update requires an amendment to FMVSS No. 108 in order to be incorporated as a requirement. Under U.S. law, amendments to Federal regulations such as FMVSS No.108 must be proposed for public comment before they can be adopted.

2. You describe a new headlamp design and ask for confirmation of your conclusion that it complies with S7.9.6.2(b) of FMVSS No. 108.

Paragraph S7.9.6.2(b) requires that:

"If the [motorcycle headlamp] system consists of two headlamps, each of which provides both an upper and lower beam, the headlamps shall be mounted either at the same height and symmetrically disposed about the vertical centerline or mounted on the vertical centerline. If the headlamps are horizontally disposed about the vertical centerline, the distance between the closest edges of their effective projected luminous lens areas shall not be greater than 200mm (8 in)."

In your design, there would be "two visibly separate headlights" which would be placed "in one seamless housing," each headlamp providing an upper and lower beam, and each lamp placed symmetrically about the vertical centerline. Further, "[o]n each side, there will be clear cover placed over the outside of the lamp." You believe that this headlamp design is allowable but report that your supplier disagrees. In his view, a headlamp is permitted a maximum of two bulbs, and that use of a single housing effectively creates a four-bulb headlamp which is not permitted.

We evaluated a similar situation in our letter of February 22, 1999, to Tadashi Suzuki of Stanley Electric Co. (copy enclosed). Our letter commented that "it is possible to design a headlamp with a single lens but with separate housings and chambers; this type of design would effectively create two headlamps." However, the supplementary information that you furnished clarifies that the Triumph headlighting system is designed to be installed in a single housing, and that the upper and lower beam headlamps are not separable from the housing. This design differs from that posited by Stanley and, in our opinion, could not be considered a two-lamp headlamp system. As such, the requirements of S7.9.6.2(b) do not apply to this design, and Triumph needs to ensure that this headlamp complies with the requirements of S7.9.6.2(a).

We would like to further comment that a headlamp with four light sources is permitted as a motorcycle headlamp. While there is a limitation on the number of light sources for motor vehicle headlamps, there is no limitation for motorcycle headlamps.

"3. Table IV of FMVSS 108 states that the minimum separation distance between a turn signal and a headlight must be 4 inches. However, since turn signals must comply with the requirements of SAE J588, does the factoring table in SAE J588 apply if we want to mount the turn signals closer to the headlights than 4 inches? If is difficult for us to decide if close mounting of turn signals is permissible as FMVSS [108] appears to preclude mounting turn signals closer than 4 inches yet J588 gives you a possibility to do so."

We were asked this question by BMW in a letter of August 15, 1983, and I enclose a copy of our response to Karl-Heinz Ziwicka. The interpretation remains valid. The minimum spacing requirements established by Table IV between motorcycle headlamps and turn signal lamps must be met, for the reasons expressed in our letter, notwithstanding the fact that SAE J588 NOV84 and its predecessor in effect at that time permit a closer spacing of these lamps if a multiplier is applied to the minimum luminous intensities.

Sincerely,
Jacqueline Glassman
Chief Counsel

Enclosures
Ref:108
d.5/24/02

ID: nht76-1.17

DATE: 07/01/76

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Parker Hannifin Corporation

TITLE: FMVSS INTERPRETATION

TEXT: This is in response to your March 24, 1976, letter concerning the application of the labeling requirements of Federal Motor Vehicle Safety Standard No. 106-74, Brake Hoses, to thermoplastic tubing of 1/8 inch nominal outside diameter that is used in "auxiliary air equipment rather than the brake system itself."

You have pointed out that it is difficult to label tubing of this diameter with letters that are 1/8 inch high, and requested an amendment of the standard to permit the labeling of such brake hoses with letters that are 1/16 inch high.

Because the tubing that you have described is not manufactured for use in the brake system itself, it is not "brake hose" as that term is defined in Standard No. 106-74 and is therefore not subject to any of the standard's requirements. In fact, although the standard does not prohibit the manufacture of air brake hose of 1/8-inch outer diameter, we are unaware at this time of the existence of any hose or tubing of that diameter that meets the definition of "brake hose". Therefore, the conformity or nonconformity of the tubing in question with the performance or labeling requirements of the standard is a matter of private contract between Parker Hannifin Corporation and those truck manufacturers that are requesting conformity.

In consideration of the possibility that 1/8-inch outer diameter tubing may in the future be used in brake systems, however, the NHTSA has decided to grant your petition to reduce to 1/16 inch the minimum required lettering height on brake hoses of such diameter. Accordingly, a proceeding respecting the issuance of a notice of proposed rulemaking has been commenced.

You should understand that our commencement of a rulemaking proceeding does not signify that the requested amendment will necessarily be issued. A final decision concerning the issuance of a proposal to amend the standard will be made on the basis of all available information developed in the course of the proceeding, in accordance with statutory criteria.

Sincerely,

ATTACH.

PARKER HANNIFIN CORPORATION

M. Schwimmer -- National Highway Traffic Safety Administration

March 24, 1976

Subject: CFR 571, STANDARD 106 SECTIONS 5.2.2 and 7.2 "MARKING"

Gentlemen:

As presently constituted, FMVSS 106 requires that the Department of Transportation marking shall be a minimum of 1/8" high. Note specifically Sections 5.2.2, 5.2.2 (a), 5.2.2 (b), 5.2.2 (c), 5.2.2 (d), and 7.2 We have determined that legible marking of this height cannot be printed efficiently by existing production equipment upon thermoplastic tubing of 1/8" nominal outside diameter. This height of letter would cover a total span of 114.5 degrees if in perfect alignment. Even with a grooved marking wheel, we have established that 60 degrees is the practical upper limit for the lettering height to span. Beyond this span, the skewed movement between type and its own printing at the top and bottom of each letter causes perceptible smudging, so that the printing actually becomes less readable instead of more so.

Major usage of 1/8" nominal outside diameter thermoplastic tubing on highway trucks seems to be in auxiliary air equipment rather than the brake system itself. Nevertheless, the truck manufacturers have required that this size conform to FMVSS 106 for safety reasons. If a complete failure of these lines should occur, they reason that the volume of compressed air supply momentarily lost could create a significant adverse effect upon the brake system. Not holding this size to the same requirements as all others would thus be inconsistent with the stated purpose of FMVSS 106:

"To reduce deaths and injuries occurring as a result of brake system failure from pressure . . . lost due to hose or hose assembly rupture."

We wish to make the following two alternative petitions in this regard:

1. We petition that the minimum lettering height of required marking on 1/8" nominal outside diameter airbrake tubing be changed from 1/8" to 1/16".

2. In the event that it is determined that the usage of 1/8" nominal outside diameter airbrake tubing lies beyond the scope of FMVSS 106, we petition for a clear directive which excludes this size from the standard and requires that it must not bear the marking called out in the sections of the standard which are referenced above.

Very truly yours,

W. E. Currie -- Chief Engineer

cc: W. Hertel; C. Foote; T. Landy

ID: nht90-2.63

TYPE: INTERPRETATION-NHTSA

DATE: 05/31/90

FROM: BARRY FELRICE -- ASSOCIATE ADMINISTRATOR FOR RULEMAKING NHTSA

TO: MIKE LOVE -- MANAGER, SAFETY COMPLIANCE PORSCHE CARS NORTH AMERICA, INC.

TITLE: NONE

ATTACHMT: LETTER FROM BARRY FELRICE -- NHTSA TO STEPHEN WOOD -- NHTSA ACTING CHIEF COUNSEL ENTITLED PORSCHE'S MODIFIED ANTITHEFT EXEMPTION, LETTER DATED 04/12/90; LETTER DATED 03/30/90 FROM MIKE LOVE -- PORSCHE TO JERRY CURRY -- NHTSA ADMINISTRATOR ON 49 CFR PART 543 EXEMPTION

TEXT: This responds to your request that this agency determine that the new feature added to the antitheft device proposed to be installed on the MY 1991 911 and 928 Porsche car lines, represents a de minimis change in the system that was the basis for the age ncy's previous granting of a theft exemption for those car lines beginning in MY 1990, and that therefore Porsche 911's and 928's containing the new device would be fully covered by that exemption.

As you are aware, the Porsche 911 and 928 car lines were granted an exemption, pursuant to 49 CFR Part 543, from antitheft marking because Porsche showed that the antitheft device to be used in lieu of marking on these car lines was likely to be as effec tive as parts marking. This exemption was issued on May 25, 1989, and appeared in the Federal Register on June 2, 1989 (54 FR 23727).

The agency granted the exemption from theft marking because the agency found that based on substantial evidence, the agency believed that the antitheft device is "likely to be as effective in reducing and deterring motor vehicle theft as compliance with the parts-marking requirements of the theft prevention standard (49 CFR Part 541)." In the granting of the exemption from theft marking, the agency stated that it believed that the device will provide the types of performance listed in 49 CFR Part 543.6( a)(3): Promoting activation; attracting attention to unauthorized entries; preventing defeat or circumventing of the device by unauthorized persons; preventing operation of the vehicle by unauthorized entrants; and ensuring the reliability and durability of the device.

In your letter, it was stated that beginning from MY 1991, Porsche plans to modify the antitheft device that is standard equipment on the Porsche 911 and 928, as follows: integrate the alarm control unit with the central locking and interior light contro l units; incorporate a feature that will also monitor the glove box for unauthorized opening; improve

P2

diagnostic capability in order to enhance serviceability; and install a capability to accept other features (such as motion sensors) if they are desired in the future.

In addition, it was stated that the changes in the system will be virtually unnoticeable to the operator, and that the system will still be armed passively by locking either door with the key. Further, with the addition of the glovebox, all the same poi nts of entry, such as the doors, hood, and hatch, will be monitored by the system and the engine disabling and alarm features will be the same. Porsche further stated that the system "will be as protected and tamper resistant as the current system."

After reviewing the proposed changes to the componentry and performance of the antitheft device on which the exemption was based, the agency concludes that the changes are de minimis. While the new device has enhanced componentry and provides some aspec ts of performance not provided by the original device, it also continues to provide the same aspects of performance provided by the original device and relies on essentially the same componentry to provide that performance. Therefore, it is not necessar y for Porsche to submit a petition to modify the exemption pursuant to 49 CFR Part 543.9(c)(2).

If Porsche does not implement the new antitheft device as described in your letter, or delays implementation until after MY 1991, we request that Porsche notify the agency of such decisions.

It is my understanding that, in an April 13, 1990 telephone conversation with Dorothy Nakama of NHTSA's Office of Chief Counsel, you stated that Porsche was not requesting confidential treatment of any information provided in your letter. Therefore, a c opy of your letter, and this response, will be placed together in NHTSA's public docket.

REF: PART 543

ID: nht95-1.89

TYPE: INTERPRETATION-NHTSA

DATE: March 6, 1995

FROM: Terry M. Habshey -- Oxy Tire Incorporated

TO: Philip Recht -- Office of Chief Counsel, NHTSA

TITLE: NONE

ATTACHMT: ATTACHED TO 5/24/95 LETTER FROM JOHN WOMACK TO TERRY M. HABSHEY (A43; STD. 109; STD. 110; STD. 119; STD. 120; PART 534; PART 575)

TEXT: Dear Mr. Recht,

Your name and address was referred to me by Ms. Terri Droneburg of the Tire I.D. and Record Keeping Dept of the National Highway Traffic Safety Administration as the person responsible for giving a legal interpretation as to our request for a D.O.T. n umber for new tires.

I am the president of a tire company located in Montevallo, Alabama just South of Birmingham off interstate Hwy 65. We are a global tire distributer involved in export only. We export mainly to second and third world markets.

We are currently constructing a new building that will house a state of the art manufacturing facility. This facility is somewhat unique in function, which is why I am sure we were directed to you. We have made arrangements to take certain quantitie s of new first line tires from many of the U.S. tire manufacturers on an ongoing basis. These tires consist of original equipment overruns, appearance blems, etc. I would point out that all the tires we receive are new and meet or exceed the minimum st andards set forth by the Department of Transportation. In accordance with our contracts, and for marketing reasons only, we remove most of the information from the sidewalls of the tires. This fact makes our project necessary.

We intend to remove, by a new process, the surface areas on both sides of the carcass (tire). This process does not expose the original cord or bead of the tire, nor does it come in contact with the original tread. It only removes a thin layer of th e sidewall rubber. This is a necessary step in the preparation of the carcass to be able to receive a new sidewall which is achieved by applying a thin layer of new rubber to be followed by the next step in our manufacturing process which is "cooking" o r vulcanizing the new sidewall onto the tire. This is achieved by a process using specially designed equipment developed specifically for this project. The equipment uses heat and light pressure to the area of the tire that needs it (the sidewall). Th is process does not expose the original tread, inner cavity, or bead to heat or pressure. When the process is complete, we have a tire that has had its sidewall remade. It will have a new registered trade name, logo, and identifying marks along with the size, safety information, mounting instructions, maximum and minimum inflating instructions, etc. We would inspect and test each tire we had performed a manufacturing function on. In addition, we currently and will continue to carry a world wide produc t liability insurance policy. We believe and hope that you will agree that this new and unique process is qualified to receive a D.O.T. number designation of our tires as new tires. Since they are, in fact new tires. I want to make it very clear, so t hat their is no misunderstanding, that each and every tire we receive is a new tire recently produced and meets all minimum standards established by the Department of Transportation.

As you know, a new recapped tire is a tire that has had thousands of miles of use and can and does in many cases have small puncture cuts and so forth on the carcass. A new tread is then reapplied which is never as reliable as the original tread.

These differences, we believe, are significant. Our tires are new, they have never been mounted or used. They are recently manufactured with original tread and new in every respect. Also, each tire will be retested by us and we will stand behind ea ch prior to selling. For these reasons we request a new D.O.T. number and wish to be the manufacturer of record. Please excuse the length of this letter, however I thought that a complete outline of all the details were necessary to facilitate your eva luation in rendering a decision. Mr. Recht, please feel free to call me at (205) 665-4771 if you have any questions regarding this project. Or, if necessary, we invite you to visit our facility at your convenience.

ID: nht94-6.47

DATE: April 7, 1994

FROM: John Womack -- Acting Chief Counsel, NHTSA

TO: Ulrich Metz -- Automotive Division, Robert Bosch GmbH (Germany)

TITLE: None

ATTACHMT: Attached to letter dated 6/9/93 from Ulrich Metz to NHTSA (OCC 9194)

TEXT:

This responds to your letter to this agency regarding a new windshield wiper system you intend to develop for front windshield. I apologize for the delay in responding.

The drawing you enclosed with your letter shows a wiper system consisting of one wiper arm and blade, as distinguished from the conventional systems consisting of two wiper arms and blades. Your wiper system takes different paths on the forward and the return strokes of the wiper cycle. Thus, as you stated in your letter, "the vision areas are fulfilled only in the sum of forward and return movement." You asked whether that is permissible under Federal Motor Vehicle Safety Standard (FMVSS) No. 104, Windshield Wiping and Washing systems (copy enclosed), and if so, whether the minimum frequencies specified by FMVSS 104 apply to this wiper system. As explained below, the answer to both questions is yes.

The essential feature of a windshield wiper system, from a safety standpoint, is its ability to clear a specific portion of the windshield. The number of wipers necessary to provide the driver with a sufficient field of view is not specified in FMVSS 104. Therefore, the number of wipers is immaterial so long as the minimum percentages of critical areas are cleared.

The areas to be wiped are specified in paragraphs S4.1.2 and S4.1.2.1 of the standard. S4.1.2 establishes three windshield areas for passenger car windshields, designated as areas "A," "B," and "C." Each area is required to have a certain percentage of the glazing area wiped as shown in Figures 1 and 2 of SAE Recommended Practice J903a, May 1966 (copy enclosed), using the angles specified in Tables I, II, III, and IV of FMVSS 104, as applicable. Those tables apply to passenger cars of varying overall widths, namely, from less than 60 inches to more than 68 inches. The angles set forth in the tables vary according to the overall width of the vehicle. Finally, paragraph S4.1.2 provides that the percentage of each area required to be cleared must also be within the area bounded by a perimeter line on the glazing surface one inch from the edge of the daylight opening.

With that background in mind, I will address your first question. FMVSS 104 does not specify whether the wiper needs to clear a windshield on either or both strokes. SAE Recommended Practice J903a, at paragraph 2.5, however, defines an effective wipe pattern as "that portion of the windshield glazing surface which is cleaned when the wiper blade travels THROUGH A CYCLE) (emphasis added). A "cycle" is defined in paragraph 2.14 of SAE Recommended Practice J903a as consisting of "wiper blade movement during system operation from one extreme of the windshield wipe pattern to the other extreme AND RETURN" (emphasis added). It is NHTSA's opinion, therefore, that so long as the required windshield area is cleared by your wiper in a complete cycle, the

requirements of paragraphs S4.1.2 and S4.1.2.1, FMVSS 104, have been met.

As indicated above, your wiper system must comply with the minimum frequencies specified in section S4.1.1, Frequency, of FMVSS 104. That section requires that each windshield wiping system must have at least two frequencies or speeds. One must be at least 45 cycles per minute (cpm), regardless of engine load and speed. The other must be at least 20 cpm, also regardless of engine load and speed. In addition, the difference between the higher and lower speeds must be at least 15 cpm, regardless of engine load and speed. There are no exceptions to these frequency requirements, regardless of the number or design of the wiper arms comprising the system.

Your letter did not indicate whether your wiper system is designed to be used on passenger cars or motor vehicles other than passenger cars, or both. Please note that section S2 of FMVSS 104, Application, provides that the standard applies to multipurpose passenger vehicles, trucks, and buses in addition to passenger cars. All those vehicles are required to have power-driven windshield wiping systems that meet the frequency requirements of section S4.1.1. The wiped area requirements of S4.1.2, however, apply only to passenger cars.

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

ID: 9194

Mr. Ulrich Metz
Automotive Division
Robert Bosch GmbH
K4/ERW3
Postfach 1163
77813 Buel
Germany

Dear Mr. Metz:

This responds to your letter to this agency regarding a new windshield wiper system you intend to develop for front windshields. I apologize for the delay in responding.

The drawing you enclosed with your letter shows a wiper system consisting of one wiper arm and blade, as distinguished from the conventional systems consisting of two wiper arms and blades. Your wiper system takes different paths on the forward and the return strokes of the wiper cycle. Thus, as you stated in your letter, "the vision areas are fulfilled only in the sum of forward and return movement." You asked whether that is permissible under Federal Motor Vehicle Safety Standard (FMVSS) No. 104, Windshield Wiping and Washing Systems (copy enclosed), and if so, whether the minimum frequencies specified by FMVSS 104 apply to this wiper system. As explained below, the answer to both questions is yes.

The essential feature of a windshield wiper system, from a safety standpoint, is its ability to clear a specific portion of the windshield. The number of wipers necessary to provide the driver with a sufficient field of view is not specified in FMVSS 104. Therefore, the number of wipers is immaterial so long as the minimum percentages of critical areas are cleared.

The areas to be wiped are specified in paragraphs S4.1.2 and S4.1.2.1 of the standard. S4.1.2 establishes three windshield areas for passenger car windshields, designated as areas "A", "B", and "C." Each area is required to have a certain percentage of the glazing area wiped as shown in Figures 1 and 2 of SAE Recommended Practice J903a, May 1966 (copy enclosed), using the angles specified in Tables I, II, III, and IV of FMVSS 104, as applicable. Those tables apply to passenger cars of varying overall widths, namely, from less than 60 inches to more than 68 inches. The angles set forth in the tables vary according to the overall width of the vehicle. Finally, paragraph S4.1.2 provides that the percentage of each area required to be cleared must also be within the area bounded by a perimeter line on the glazing surface one inch from the edge of the daylight opening.

With that background in mind, I will address your first question. FMVSS 104 does not specify whether the wiper needs to clear a windshield on either or both strokes. SAE Recommended Practice J903a, at paragraph 2.5, however, defines an effective wipe pattern as "that portion of the windshield glazing surface which is cleaned when the wiper blade travels through a cycle) (emphasis added). A "cycle" is defined in paragraph 2.14 of SAE Recommended Practice J903a as consisting of "wiper blade movement during system operation from one extreme of the windshield wipe pattern to the other extreme and return" (emphasis added). It is NHTSA's opinion, therefore, that so long as the required windshield area is cleared by your wiper in a complete cycle, the requirements of paragraphs S4.1.2 and S4.1.2.1, FMVSS 104, have been met.

As indicated above, your wiper system must comply with the minimum frequencies specified in section S4.1.1, Frequency, of FMVSS 104. That section requires that each windshield wiping system must have at least two frequencies or speeds. One must be at least 45 cycles per minute (cpm), regardless of engine load and speed. The other must be at least 20 cpm, also regardless of engine load and speed. In addition, the difference between the higher and lower speeds must be at least 15 cpm, regardless of engine load and speed. There are no exceptions to these frequency requirements, regardless of the number or design of the wiper arms comprising the system.

Your letter did not indicate whether your wiper system is designed to be used on passenger cars or motor vehicles other than passenger cars, or both. Please note that section S2 of FMVSS 104, Application, provides that the standard applies to multipurpose passenger vehicles, trucks, and buses in addition to passenger cars. All those vehicles are required to have power-driven windshield wiping systems that meet the frequency requirements of section S4.1.1. The wiped area requirements of S4.1.2, however, apply only to passenger cars.

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

Sincerely,

John Womack Acting Chief Counsel

Enclosures ref:104 d:4/7/94

ID: nht70-2.24

DATE: 09/03/70

FROM: AUTHOR UNAVAILABLE; Douglas W. Toms; NHTSA

TO: General Motors Corporation

TITLE: FMVSR INTERPRETATION

TEXT: On August 13, 1970, you petitioned, on behalf of General Motors Corporation, for reconsideration of the amendment of 49 CFR 571.3, published on July 14, 1970 (35 F. R. 11242), which established a definition of "fixed collision barrier". The views presented in your petition have been carefully considered. For the reasons stated below, your petition is denied.

You argued that the phrase "absorb no significant portion of the vehicle's Kinetic energy" was subjective, and therefore not in accord with the statutory requirement that standards be stated in objective terms. This argument is without merit. It appears to be based on the misconception that the purpose of the definition is to describe, or prescribe standards for, a manufacturer's test barrier, as evidenced by your statement that it "gives manufacturer no guidelines for determing whether or not he has built a barrier which complies with the definition." The Bureau does not intend that manufacturers should build barriers to "comply with the definition." As stated in the notice,

"this is not intended to be a description of an actual test barrier. It is a device used in various standards to establish required quantitative performance levels of a vehicle in a crash situation, and means simply that the vehicle must meet the requirement no matter how small an amount of energy is absorbed by the barrier."

Far from being subjective, the definition is mathematically precise. As the energy absorption of the barrier approaches zero as a limit, the performance characteristic being measured must remain at or above the minimum stated in the standard.

From a practical standpoint, the definition is an important aid in regulation, and is a help to all parties in that a potential source of controversy concerning compliance with the standards is removed. It simply means that when the Bureau crash-tests a vehicle, the vehicle must meet the requirement no matter what the energy-absorption properties of the barrier, and therefore there is no room for argument on the differing properties of the Bureau's and the manufacturer's test barriers. The purpose of the standards is to regulate vehicles and equipment, not test barriers; manufacturers may use whatever barriers or tests they wish to ensure compliance It is a reasonably simple matter to erect a barrier that absorbs only a minute fraction of an impacting vehicle's energy. A conscientious manufacturer should therefore have no difficulty in determining whether a particular design will meet a standard.

Your petition also argued that the definition was impracticable because

"there is no known method of measuring the amount of energy absorbed by a barrier. Therefore, there is no way that the manufacturer could even attempt to determine whether or not his barrier complied with the definition, and, more importantly, whether or not his vehicle when tested complied with the performance requirements of the standards."

The energy absorption of a barrier is a direct function of the movement of the barrier during the impact. To be sure, there are other properties, such as its effective mass and elasticity, that also are factors in energy absorption. But it is clear that as the barrier movement approaches zero, the energy absorption also approaches zero; and the barrier movement can be measured, as you indicated by your recommendation that a specified amount of movement be allowed. In all cases where the vehicle has a tangible margin of safety performance over the required minimum, therefor, a manufacturer will have no difficulty in determining that his vehicle complies,

If our standards "allowed" barrier movement, it would be far more difficult to establish conclusively that a given vehicle did not meet the standard, since it would always be open to the manufacturer to argue that the Bureau's barrier did not move as far, and consequently did not absorb as much energy, as the standard allowed. To the extent that there may be a small degree of uncertainty as to the variance is the vehicle test performance caused by the variance of a barrier from zero absorption, that uncertainty must rest with the manufacturer, who is free to design into his vehicles whatever margin of performance he desires.

This matter was thoroughly considered by the Bureau, and the opinions of knowledgeable members of the public were sought and carefully evaluated. For these reasons, your petition for reconsideration must be denied.

We appreciate your cooperation in the field of motor vehicle safety.