ID: 9166

The Honorable Ken Calvert
Member, United States House of
Representatives
3400 Central Avenue, Suite 200
Riverside, CA 92506

Dear Mr. Calvert:

Thank you for your letter on behalf of your constituent, Mr. Alexander H. Patnode of Lake Elsinore, concerning an engine stand your constituent purchased from Pep Boys. Mr. Patnode asked for assistance after the engine stand caused the engine to fall, injuring his ankle.

As explained below, the National Highway Traffic Safety Administration (NHTSA) considers the engine stand to be "motor vehicle equipment," subject to our regulation. NHTSA has authority to issue Federal motor vehicle safety standards for new motor vehicles and new items of motor vehicle equipment. 49 U.S.C. section 30102(a)(7) defines "motor vehicle equipment" in relevant part as:

(A) any system, part, or component of a motor vehicle as originally manufactured; (B) any similar part or component manufactured or sold for replacement or improvement of a system, part or component, or as an accessory, or addition to a motor vehicle... (emphasis added)

Although an engine stand is not a system, part, or component of a motor vehicle, it would be considered an "accessory" to a motor vehicle. NHTSA has typically used two criteria in determining whether a product is an "accessory." The first criterion is whether a substantial portion of the expected use of the item is related to the operation or maintenance of motor vehicles. Expected use is determined by considering product advertising, product labeling, the type of store that sells the equipment, and information about how the product is used. The second criterion is whether the product is intended to be purchased or otherwise acquired, and principally used by, ordinary users of motor vehicles. If a product satisfies both criteria, it is deemed an "accessory."

We have determined the engine stand is an accessory, and thus an item of motor vehicle equipment. Applying the two criteria

to the engine stand, (1) the engine stand is intended to be used in the maintenance of motor vehicle engines, and (2) assuming the stand was new when sold to Mr. Patnode, it was intended to be acquired and used by ordinary users of motor vehicles.

We have searched our files by computer for reported complaints about engine stands, and for manufacturers' service bulletins and recalls. The search was conducted according to manufacturer (Rally) and equipment type (motor vehicle equipment: jacks, and other). A summary of the search results is enclosed. We found no reported instance of an injury caused by an engine stand, or of a manufacturer's issuing a service bulletin or recall because of an engine stand problem.

We will keep a copy of Mr. Patnode's letter in our files on reported complaints. In the future, the letter may be helpful in establishing a pattern of safety-related concerns caused by the type of engine stand that resulted in Mr. Patnode's injury.

I hope this information is helpful. If there are any questions, please let me know.

Sincerely,

John Womack Acting Chief Counsel

Enclosure

cc: Harleigh Ewell, Esq. Office of the General Counsel Regulatory Affairs Division U.S. Consumer Product Safety Commission Washington, D.C. 20207-0001 ref:vsa102(4) d:6/18/95

ID: 9172

Thomas G. Cehelnik, Ph.D.
Accutron T.C.S., Inc.
Box 821 RD 1
Scottsdale, PA 15683

Dear Dr. Cehelnik:

We are replying to your letter of September 28, 1993, requesting information on Federal Motor Vehicle Safety Standard No. 108 (you will find the complete text of this standard at 49 CFR 571.108).

Your company has developed "a light system to indicate the deceleration of the vehicle." You have been informed that this agency is "investigating the safety of such a device," and "that lights that indicate braking must be `steady- burning.'" The agency is not investigating deceleration warning systems, thus I am unable to provide you with "information on the status of the safety investigation" as you requested. Paragraph S5.5.10 of Standard No. 108 applies to all lamps provided as original motor vehicle equipment, and lists the lamps that may flash, such as turn signal lamps, but this list does not include stop lamps. A final catchall subparagraph (d) requires that "[a]ll other lamps shall be wired to be steady-burning," and this includes stop lamps.

You also asked "is it and will it become legal to turn on a warning or stop light that indicates the particular dynamic state of the vehicle?" and "[m]ust such a system necessarily be considered as a brake light?" We have encountered some deceleration warning systems that activate the stop lamps by means other than application of the service brake pedal. This is prohibited by paragraph S5.5.4 which states that "[t]he stop lamps on each vehicle shall be activated upon application of the service brakes." We have interpreted this as meaning that the stop lamps may be activated only by application of the service brakes, and that they may not be activated by reduced pressure on the accelerator pedal. A stop lamp can only be operated to indicate that the brake pedal has been applied for the purpose of slowing or stopping a vehicle. You may find of interest a letter of interpretation which I enclose (letter to Larry Snowhite, January 25, 1990) which expresses more fully our views on this subject.

Sincerely,

John Womack Acting Chief Counsel

Enclosure

ref:108 d:10/22/93

ID: 9173

Mr. Joe Takacs
Director of Engineering
Kinedyne Corporation
3701 Greenway Circle
Lawrence, KS 66046-5442

Dear Mr. Takacs:

This responds to your letter of September 21, 1993 in which you referred to this agency's final rule amending Federal Motor Vehicle Safety Standard (FMVSS) No. 222, School Bus Passenger Seating and Crash Protection, dated September 3, 1993 (58 FR 46873). You requested our interpretation of that notice as to whether the following is acceptable:

1. The webbing Kinedyne uses in its wheelchair strap assemblies is industrial-type 1 or 2-inch polyester webbing that meets the strength and other requirements of S4.2 of FMVSS 209.

2. The hardware Kinedyne uses on its wheelchair strap assemblies are industrial-type 1 or 2-inch overcenter, ratchet or cam buckles; wire hooks; snap hooks and track fittings, all of which meet the strength and other requirements of S4.3 of FMVSS 209.

With regard to the webbing used in your strap assemblies, paragraph S4.2(a), FMVSS 209, provides that seat belt webbing cannot be less than 1.8 inches in width "except for portions that do not touch a 95th percentile adult male with the seat in any adjustment position and the seat back in the manufacturer's nominal design riding position . . . ." That means that seat belt webbing must be 1.8 inches in width only where it touches the person of the occupant. The width of webbed belts or straps which secure a wheel chair to the bus floor and do not touch the person of the occupant is not specified in any standard. Accordingly, Kinedyne is free to use belts of 1 inch or some other width, so long as such belts do not touch the person of the occupant and meet the other requirements of S4.2, FMVSS 209.

S4.3 of FMVSS 209 addresses a number of requirements for seat belt hardware, including corrosion and temperature resistance, attachment hardware, buckle release, adjustment force, retractor requirements (if applicable), etc. If the hardware Kinedyne uses in fact meet all those requirements, then it would be acceptable. I hope this information is helpful to you. If you have any further questions or need any further 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

ref:222#209 d:11/23/93

ID: 9176

Mr. Timothy McQuiston
Vice-President Sales
California Dream
P.O. Box 11
Waukesha, WI 53187

Dear Mr. McQuiston:

This is in reply to your letter of September 29, 1993, to Taylor Vinson of this Office. Your company provides an aftermarket spoiler which incorporates a center stop lamp "that complies with SAE standards." You have asked us for a statement that you could provide your dealers that "would affirm that when the dealer installs a spoiler containing a high mount third brakelight meeting/exceeding SAE standards, they are, in fact providing an equivalent light source, thereby allowing them (dealers) to remain in compliance with federal regulations." You have also enclosed a November 1992 report from ETL Testing Laboratories rendered to Leegold Enterprise Co., Ltd. covering the lamp that we assume to be the one you are offering in your spoiler.

Under the National Traffic and Motor Vehicle Safety Act (15 U.S.C. 1381 et seq.), in the fact situation you present, the dealer has the following obligations with respect to new and used vehicles. It is obliged to deliver a new vehicle to the buyer with a center highmounted stop lamp that is in full compliance with Federal Motor Vehicle Safety Standard No. 108, and if it does not, it may be in violation of section 108(a)(10(A) of the Act (15 U.S.C. 1397(a)(1)(A)). With respect to a vehicle in use, under section 108(a)(2)(A) of the Act, it may not knowingly render inoperative, in whole or in part, the original center highmounted stop lamp unless it provides a conforming equivalent (agency interpretation of 15 U.S.C. 1397(a)(2)(A)).

Therefore, as a general principle, we affirm your understanding that a dealer may knowingly render an original equipment center highmounted stoplamp inoperative on a vehicle in use, or cause it on a new vehicle to become noncompliant with the requirements of Standard No. 108 if the dealer provides a substitute lamp that meets Standard No. 108's requirements. The test report you provided indicates that the Model LG 03-60B lamp that was tested meets requirements specified in Standard No. 108 and SAE Recommended Practice J186a, and that that particular lamp is an equivalent in performance to an original equipment light source.

Having said that, however, we feel that further comments are in order. The first comment is to clarify a misunderstanding reflected in your letter. The lamp must comply with Standard No. 108, and not with SAE specifications as you have stated. Although Table III of Standard No. 108 does incorporate by reference SAE Recommended Practice J186a, "Supplemental High Mounted Stop and Rear Turn Signal Lamps," September 1977, certain provisions of J186a, such as photometrics, do not apply because they have been modified by the text of Standard No. 108 itself. We are pleased to note that the summary of the test report appears to recognize this distinction.

Our second comment is that, in addition to the assurances that you as the spoiler manufacturer provide the dealer, both you and the dealer are afforded a degree of protection from violations of the Act if Leegold's lamp, in fact, fails to meet Standard No. 108. This is true whether the dealer installs the spoiler either as original equipment or as aftermarket equipment.

With respect to original equipment (i.e., installed before delivery of the vehicle to its first purchaser), Leegold, as the manufacturer of the lamp, is required by section 114 of the Act (15 U.S.C. 1403) to certify to its dealers and distributors that the lamp complies with Standard No. 108 (which may be signified by the symbol "DOT" on the lamp). If the lamp is later discovered to be noncompliant, those who have sold the lamp and any new vehicle on which it has been installed are in technical violation of the Act, but are protected by section 108(b)(1) of the Act from civil penalties, unless they have actual knowledge that the lamp does not meet Standard No. 108 (15 U.S.C. 1397(b)(1)).

With respect to a nonconforming lamp installed after the vehicle's first sale, the original lamp may have been disconnected or partially blocked by the aftermarket lamp, resulting in either case in a "rendering inoperative" of required equipment within the meaning of the prohibition. However, we would not view this as a "knowingly" rendering inoperative because the dealer's intent is to install a conforming lamp, as indicated by the lamp's certification.

One final comment, one directed more to Leegold than to your or your dealers. As a result of our experience over the years, we have come to realize the value of surveillance testing of production lamps to assure that the lamps continue to comply with Federal requirements. Periodic testing may be regarded as evidence of the manufacturer's exercise of due care in the event of noncompliances. If the November 1992 ETL test is of a prototype lamp, Leegold may wish to have new tests conducted on production lamps. Even if that test were of production lamps, sufficient time has elapsed, in our view, for Leegold to conduct a new test, to ensure that design tolerances have been maintained in production and that the lamp continues to conform to Standard No. 108.

Sincerely,

John Womack Acting Chief Counsel ref:108 d.1/26/94

ID: 9181

Mr. James E. Walker III
Manager, LSI Laboratories
Lighting Sciences, Inc.
7830 E. Evans Road
Scottsdale, AZ 85260

Dear Mr. Walker:

We are replying to your letter of October 4, 1993, with respect to the requirements of Federal Motor Vehicle Safety Standard No. 108 for taillamps.

You believe that a discrepancy exists because paragraph S5.1.1 "requires equipment to be designed to Tables I, II [you mean III], and S7, which references SAE J585e for the Tail Lamp," whereas paragraph S5.1.1.11 "requires Table 1 of this specification to be substituted for the values achieved by Figures 1a and 1b, and in addition, to substitute Table 1 of SAE J585e by the values achieved by multiplying the percentages of Figure 1a by Table 1 and 3 of SAE J588 NOV84 Turn Signal Lamps."

You assume that the photometric requirements are those of Figure 1a, 1b, and 1c. Your assumption is correct. However, there is no discrepancy in the standard. The requirements for motor vehicle lighting equipment are set forth in Section S5. Paragraph S5.1.1 requires lighting equipment to comply with the SAE materials contained in the tables, except as may be provided in succeeding paragraphs of Paragraph S5.1.1. Tables I and III incorporate by reference SAE Standard J585e, Tail Lamps, September 1977. However, on March 3, 1993, NHTSA redesignated Paragraph S5.1.1.11 (with its references to Figures 1a and 1b) as S5.1.1.6, and revised it to include, among other things, the reference in paragraph S5.1.1.12 to Figure 1c. The same notice removed paragraph S5.1.1.12 from the standard. New Paragraph S5.1.1.6 states that instead of the photometric values specified in Table 1 of SAE J585e, taillamps shall comply with those of Figures 1a, 1b and 1c.

I enclose a copy of the amendment for your information, and hope that this answers your question.

Sincerely,

John Womack Acting Chief Counsel Enclosure ref:108 d:11/16/93

ID: 9182

Mr. Dennis G. Moore
President
Sierra Products Inc.
1113 Greenville Road
Livermore, CA 94550

Dear Mr. Moore:

We have received your letter of September 29, 1993, with reference to the location requirements of Standard No. 108 for identification (i.d.) lamps.

Table II of the standard in pertinent part specifies the following location for i.d. lamps: "On the rear - 3 lamps as close as practicable to the top of the vehicle at the same height, as close as practicable to the vertical centerline . . . ." You reference at least two instances in the past 20 years or longer in which "NHTSA has allowed the slight misalignment of I.D. lights because of `Practical' circumstances," and have asked for copies of these interpretations.

We are unaware of these interpretations. In their absence, you have asked for an interpretation of the phrase "at the same height" that would permit the mounting height of the center lamp to deviate slightly from the height of the two lamps that flank it, as shown in your letter. You depict two other possible configurations in which the three lamps are mounted at identical heights. In one configuration, the lower edges of the outboard lamps hang below the frame "making them vulnerable to being damaged or knocked off" in your opinion. In the second configuration, the lamps are raised and protected, but the center lamp is somewhat obscured by the "typical roller or protective pad." You deem these configurations undesirable for safety reasons.

The question to be answered is whether the configuration you prefer is "as close as practicable to the top of the vehicle at the same height" (note the absence of a comma between "vehicle" and "at"). The determination of practicability is initially that of the manufacturer. Unless it is clearly erroneous, NHTSA will not question it. In the absence of a superstructure, the frame location may be regarded as being "as close as practicable to the top of the vehicle. . . ." Because "at the same height" is part of the same phrase, practicability also governs placement of the lamps at the same height. A manufacturer may determine that, for the sake of practicability, i.d. lamps may be mounted at a height sufficient to protect them from breakage (the outboard lamps) and to ensure compliance with photometric requirements (the center lamp). The configuration you depict is sufficiently close to the literal reading of the phrase "at the same height" that NHTSA would not question the manufacturer's determination of practicability with respect to the mounting height of the center i.d. lamp.

Sincerely,

John Womack Acting Chief Counsel

ref:108 d:11/16/93

ID: 9183

Mr. Mark Archer
Orbital Engine Company Pty. Ltd.
1 Whipple Street, Balcatta 6021
Western Australia
Australia

Dear Mr. Archer:

This responds to your letter in which you asked if the National Highway Traffic Safety Administration (NHTSA) has any regulations affecting a vehicle that has an automatic engine shut-off device that operates when the vehicle remains idle for extended periods. I regret the delay in responding.

By way of background information, NHTSA administers Federal requirements for the manufacture and sale of new motor vehicles and certain items of motor vehicle equipment. The National Traffic and Motor Vehicle Safety Act ("Safety Act," copy enclosed) establishes a "self-certification" process under which each manufacturer is responsible for certifying that its products meet all applicable Federal motor vehicle safety standards (FMVSS's). This process requires each manufacturer to determine in the exercise of due care that its products meet all applicable requirements. NHTSA tests vehicles and equipment sold to consumers for compliance with the FMVSS's and investigates defects relating to motor vehicle safety. If a manufacturer or NHTSA determines that a noncompliance or safety-related defect exists, the manufacturer must notify purchasers of its product and remedy the problem free of charge. A manufacturer of a noncomplying product is also subject to a civil penalty of up to $1,000 for each noncomplying item it produces. I have enclosed an information sheet that highlights these responsibilities.

We cannot tell from your letter whether you seek to produce a vehicle that has a shut-off device installed as original equipment ("O.E."), i.e., prior to a first sale to a consumer, or produce the device as an "aftermarket" item of equipment, sold for installation in used vehicles. We will discuss both situations in this letter.

A shut-off device may not be installed on a new vehicle if the device causes the vehicle not to comply with all applicable FMVSS's. Standard No. 102, "Transmission shift lever sequence, starter interlock, and transmission braking effect," states that "the engine starter shall be inoperative when the transmission shift lever is in a forward or reverse drive position." (S3.1.3). NHTSA does not know of any shut-off device that would enable a vehicle to meet S3.1.3 of Standard 102. In 1984, NHTSA terminated rulemaking on an action that would have amended S3.1.3 to permit a shut-off device that restarted the vehicle's engine when the accelerator is depressed. A copy of the termination notice is enclosed. The agency terminated rulemaking citing a number of safety concerns with the particular features of the shut-off device that was the subject of the rulemaking. NHTSA stated in the notice that, if in the future a more effective and safe fuel saving device is developed, NHTSA would again consider amending Standard 102. However, given that S3.1.3 of Standard 102 was not amended, that section precludes the O.E. installation on a shut-off device such as the one described in the termination notice.

With respect to the aftermarket installation of a shut-off device, there is currently no FMVSS that directly applies to the product. Standard 102 applies only to new motor vehicles and not to aftermarket components of a vehicle's transmission, such as a shut-off device.

However, there are other Federal requirements that indirectly affect the manufacture and sale of a shut-off device. Under the Safety Act, the product is considered to be an item of motor vehicle equipment. As explained above, each manufacturer of motor vehicle equipment is subject to the requirements in 151-159 of the Safety Act concerning the recall and remedy of products with safety related defects. In the event that the manufacturer or NHTSA determines that the product contains a safety-related defect, the manufacturer would be responsible for notifying purchasers of the defective equipment and remedying the problem free of charge.

Manufacturers, distributors, dealers, and motor vehicle repair businesses are subject to 108(a)(2)(A) of the Safety Act, which states: "No manufacturer, distributor, dealer, or motor vehicle repair business shall knowingly render inoperative ... any device or element of design installed on or in a motor vehicle or item of motor vehicle equipment in compliance with an applicable Federal motor vehicle safety standard ...." This means that if a shut-off device were sold in the "aftermarket," no manufacturer, distributor, dealer, or motor vehicle repair business could install it if doing so would render inoperative any previously certified item of equipment in the vehicle. As explained above, each motor vehicle is certified as meeting Standard 102. A shut-off device that causes the vehicle to no longer comply with Standard 102 could not be installed by any person listed in section 108(a)(2)(A) without subjecting that person to civil penalties (section 109 of the Safety Act specifies a civil penalty of up to $1,000 for each violation of 108).

The "render inoperative" prohibition of 108(a)(2)(A) does not apply to the actions of vehicle owners in adding to or otherwise modifying their vehicles. However, NHTSA urges all owners not to perform modifications that would degrade the safety of their vehicles, such as installing a fuel shut-off device that raises significant safety concerns.

I hope this responds to your concerns. If you have any further questions, please contact David Elias of my staff at this address or by telephone at (202) 366-2992.

Sincerely,

John Womack Acting Chief Counsel

Enclosures

ref:102 d:4/5/94

ID: 9189

Mr. Milford R. Bennett, Head
Safety Affairs and Operations
NAO Engineering
Safety Center
General Motors Corporation
30200 Mound Road/S3-N27
Warren, MI 48090-9010

Dear Mr. Bennett:

This is in reply to your letter of October 7, 1993, to Howard Smolkin concerning information labels for vehicles covered by NHTSA temporary exemptions (49 CFR Part 555).

Paragraph 555.9(b) requires that a windshield or side window label containing an advisory statement be affixed securely to each exempted vehicle. You have concluded that this label is intended to notify prospective purchasers that the vehicle has been exempted from compliance with certain Federal motor vehicle safety standards. Because General Motors (GM) does not intend to sell its recently exempted GMEV, it believes that it is not required to place the label on its vehicles.

Section 123(b) of the National Traffic and Motor Vehicle Safety Act (the Act) (15 U.S.C. 1410(b)) specifies that "[t]he Secretary may require that written notification of [an] exemption be delivered to the dealer and first purchaser for purposes other than the resale of such exempted motor vehicle in such manner as he deems appropriate." NHTSA chose to exercise this discretionary power through promulgating paragraph 555.9(b) requiring windshield and side window labels on exempted vehicles, commenting that "[t]he window label appears to be the most appropriate way of providing written notification of exemptions to dealers and first purchasers" (37 FR 25534).

We read in The New York Times on October 14, 1993, that GM will build 50 Impacts (presumably the exempted GMEVs) "and lend them for two to four weeks to 1,000 drivers around the country over the next two years, with the help of 14 utilities." If these cars are made available through GM's dealer network, then we believe that the label should nevertheless be provided even if the vehicle is not sold, and that it should remain affixed until the vehicle is first lent or leased through the dealer. Although subsequent users of the GMEV will not have access to the temporary label in order to evaluate the risk they assume by accepting temporary use of a nonconforming motor vehicle, the permanently affixed exemption certification label will furnish this information should they care to consult it.

Sincerely,

John Womack Acting Chief Counsel

ref:555 d:10/22/93

ID: 9190

Mr. Michinori Hachiya
Director and General Manager
Nissan Research and Development, Inc.
750 17th Street, N.W.
Suite 902
Washington, DC 20006

Dear Mr. Hachiya:

This responds to your letter of October 12, 1993, asking several questions concerning the labeling requirements of the recent final rule mandating the installation of air bags in passenger cars and light trucks (58 FR 46551, September 2, 1993). Your questions concern the labeling requirements in this final rule.

As you may know, NHTSA has received two petitions for reconsideration of the September 2 final rule. The petitions raise issues concerning the labeling requirements. We will address your first, second, and fourth questions in the notice responding to the petitions for reconsideration.

Your other questions and the response to each follow.

The mandatory air bag rule establishes type size and format requirements for the air bag maintenance label (section 4.5.1(a)), but no similar requirements for the air bag warning label in section 4.5.1(b). Are we correct in understanding that the lettering of the warning label may be of any size or format, so long as the letters are legible? May different type size and formats be used if the two labels are combined?

You are correct that there are not any size requirements for the air bag warning label. Therefore, so long as the information on the label is legible, the lettering may be of any size. It is unclear what you mean by format, but the warning label must contain the exact words, in the exact order, as specified in section 4.5.1(b). The issue of combining warning and maintenance labels will be addressed in the notice responding to the petitions for reconsideration.

It is our understanding that warning labels that do not refer to air bags or seat belts may continue to be placed on the side of the sun visor opposite from the air bag warning label. Nissan currently places a label on the sun visor of a convertible model which provides instructions regarding the use of the convertible top. May this type of label continue to be placed on the sun visor, so long as it is on the side of the visor opposite from the air bag warning label?

Section S4.5.1(b)(2) specifies (1) that no other information shall be on the same side of the sun visor as the air bag warning label, and (2) that no other information concerning air bags or seat belts shall appear anywhere on the sun visor. Therefore, you are correct that information concerning the operation of a convertible top could be placed on the side of the sun visor opposite the side with the air bag warning label.

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

Sincerely,

John Womack Acting Chief Counsel

ref:208 d:11/18/93

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