ID: 9197-3

Thomas D. Price, President
Strait-Stop
ABAS Marketing, Inc.
P.O. Box 5644
Norman, OK 73070

Dear Mr. Price:

This responds to your letter concerning this agency's notice of proposed rulemaking (NPRM) to require medium and heavy vehicles to be equipped with an antilock braking system (58 FR 50739, September 28, 1993). You noted that the proposed definition for "antilock brake system" incorporates the terminology "rate of angular wheel rotation," and requested a definition of this terminology. You also suggested that there is ambiguity as to the precise meaning of the word "performance," apparently with respect to the way that word is used in the preamble. Accordingly, you requested a definition of that word as well.

By way of background information, the purpose of publishing NPRM's is to provide all interested persons an opportunity to comment on regulations being considered by the agency. If an interested person believes that the proposed regulatory text and/or the agency's explanation in a preamble concerning a proposed regulation are unclear, the appropriate place to make that argument is in a comment on the NPRM. If a person believes that a portion of the proposed regulation should be clarified in a particular manner, that recommendation also should be included in a comment. Similarly, if a person believes the agency's explanation for the proposed rule is unclear, the person can identify in comments the portion of the explanation at issue and explain the implications his or her concern has on the agency's decision concerning a possible final rule.

Since the questions and views in your letter are in the nature of comments on the pending NPRM, we are placing a copy of your letter in the public docket for that NPRM. I want to assure you that your comments will be considered at the same time all the other public comments are considered. Only after considering the comments will NHTSA reach a decision on whether to issue a final rule.

NHTSA does not issue separate letters or documents responding to individual public comments in a rulemaking. Instead, after carefully considering all comments, NHTSA provides its responses in the next relevant rulemaking notice, e.g., a final rule or a notice terminating the rulemaking.

While we cannot provide specific responses to your questions, we note that pages 50742 and 50743 of the NPRM provide an extensive discussion about how the agency derived its definition for antilock braking system. This discussion explains that the definitions were derived in large part from the Society of Automotive Engineers (SAE) Recommended Practice J656, "Automotive Brake Definitions and Nomenclature" (1988), and the Economic Commission for Europe's Regulation 13 (1988). We have enclosed for your information a copy of that SAE Recommended Practice, which uses the terminology "rate of angular rotation of the wheel(s)."

With respect to your question about the meaning of "performance," we note generally that each of this agency's safety standards specifies those requirements that are deemed necessary to obtain the desired safety performance from a particular vehicle system or item of equipment. Any design that will satisfy the requirements may be used for the system or item of equipment.

I hope this information is helpful.

Sincerely,

John Womack Acting Chief Counsel

Enclosure ref:121 d:1/3/94

ID: 9199

The Honorable Phil Gramm
United States Senate
2323 Bryan Street, #1500
Dallas, TX 75201

Dear Senator Gramm:

Thank you for your inquiry on behalf of your constituent, Mr. Thomas J. Devon of Longview, Texas. The Federal Highway Administration (FHWA) referred your inquiry to this office, since the National Highway Traffic Safety Administration (NHTSA) administers Federal safety standards for tires.

In his communication with you, Mr. Devon expressed concern about separated treads from retreaded large truck tires. He referred to the deaths of two young women reportedly caused when they lost control of their vehicle after striking a separated tread in the road. Mr. Devon is concerned that retreaded tires do not meet the same standards as new tires and requested data on accidents caused by separated tire tread sections on the roadway.

By way of background information, the National Traffic and Motor Vehicle Safety Act of 1966, 15 U.S.C. 1381, et seq. (Safety Act) authorizes NHTSA to issue safety standards applicable to new motor vehicles and new items of motor vehicle equipment. Pursuant to that authority, NHTSA has issued various Federal Motor Vehicle Safety Standards (FMVSS) applicable to tires: FMVSS Nos. 109 and 110 for new pneumatic passenger car tires; FMVSS Nos. 119 and 120 for new pneumatic tires for other than passenger cars; and FMVSS No. 117 for retreaded passenger car tires. There is currently no standard applicable to retreaded tires for vehicles other than passenger cars. This is because the agency is not aware of any data suggesting a safety need for such a standard.

With respect to tire tread separation, examination of actual tire scraps from the nation's highways have indicated that about 60 percent came from retreaded tires and 40 percent from original tires. Because of the many complaints about heavy truck tire tread scraps on and around the highways, the University of Michigan conducted a study in the mid-1980s entitled "Large Truck Accidents Involving Tire Failure." That study concluded that most large truck tire failures are caused by vehicle overload and/or tire underinflation. Underinflation causes excessive flexing of the tire. The friction resulting from that flexing causes excessive heat buildup which can, in turn, result in tread separation or other tire failure. Indeed, the heat buildup has been known to be so extreme as to cause the tire to burst into flame.

The findings from the Michigan study led the FHWA to prohibit the operation of commercial motor vehicles with overloaded and underinflated tires, unless the vehicle is operated pursuant to a special permit issued by a state. That permit, however, requires a reduced speed to compensate for the increased tire loading. In addition, the vehicle and the tires must be maintained in a safe operating condition at all times. FHWA conducts roadside inspection programs to ensure that such requirements are being met.

While scraps of tires on the roadway could pose a safety hazard to motorists, this agency has no real world crash data to indicate what percentage of motor vehicle crashes could be attributed to separated tire treads. Our crash data are limited to the general category of tire failure.

Please be assured that NHTSA and FHWA, as well as the tire industry itself, are engaged in ongoing efforts to alleviate this problem by appropriate publicity to large truck owners and operators regarding proper tire care and maintenance and by vigorous vehicle inspection programs.

I hope this information is helpful. If your constituent has any further questions, he may contact Walter Myers of this office at this address or at (202) 366-2992.

Sincerely,

John Womack Acting Chief Counsel

Enclosure Constituent's Correspondence

ref:117 d:11/3/93

ID: 9204

Mr. Donald E. Schmitz
Engineering Manager
Featherlite Mfg., Inc.
P.O. Box 380
Cresco, IA 52136

Dear Mr. Schmitz:

This responds to your letter of October 7, 1993, to Acting Administrator Smolkin which "addresses the TTMA, September 8, 1993, Recommended Practice on Trailer Conspicuity Systems." You inform us that you "will begin applying the conspicuity tape to the trailer's bottom as shown" in the TTMA sketches, and "will assume our interpretation is correct . . . unless we receive a response from your office within ten days."

If you wish an interpretation of the TTMA drawings, you should consult that organization. This agency provides interpretations of Federal Motor Vehicle Safety Standard No. 108, Lamps, Reflective Devices, and Associated Equipment. With respect to paragraph S5.7, which establishes conspicuity system requirements for large trailers, effective December 1, 1993, the agency published an amendment on October 6, the day before your letter, which modified the mounting height requirements adopted in December 1992. The original requirement of "as close as practicable to 1.25 m above the road surface" has been changed to a range that is "as close as practicable to not less than 375 mm and not more than 1525 mm above the road surface. . . ." I enclose a copy of the amendment for your information. See paragraph S5.7.1.4.2(a) for the change.

Sincerely,

John Womack Acting Chief Counsel

Enclosure

ref:108 d:11/16/93

ID: 9205

Mr. Saburo Inui
Vice President
Toyota Motor Corporate Services
of North America, Inc.
1850 M Street, N.W.
Washington, D.C. 20036

Dear Mr. Inui:

This responds to your letter asking about the test conditions for the dynamic side impact test of Standard No. 214, "Side Impact Protection." I apologize for the delay in responding.

The test conditions are set forth in S6 of the standard. S6.1 explains how to achieve "test weight:"

Test weight. Each passenger car is loaded to its unloaded vehicle weight, plus its rated cargo and luggage capacity, secured in the luggage area, plus the weight of the necessary anthropomorphic test dummies. Any added test equipment is located away from the impact areas in secured places in the vehicle. * * *

You first ask whether the weight of the added test equipment inside the vehicle is added to the test weight, or whether parts of the vehicle (weighing the same as the "added test equipment") are removed to keep the vehicle weight at the "test weight." The answer is that parts of the vehicle may be removed, but only as a last resort. A brief explanation of how NHTSA calculates test weight follows.

Under S6.1, "test weight" is comprised of the combined weight of the vehicle with all fluids, the cargo and luggage weight, the test dummies, and nothing more. The cargo and luggage weight is derived by subtracting from the gross vehicle weight rating specified by the manufacturer the combined weight of the vehicle, fluids, and 150 pounds for each seating position.

There are subtractions and additions to the vehicle weight in preparation for the test. The fuel is replaced with Stoddard solvent, but only to approximately 93 percent of capacity, and all other fluids (oil, washer fluid, etc.) are drained. Thus, the vehicle is lightened by the weight of 7 percent of the

fuel and all of the other fluids. However, the added weight of cameras and any other necessary (non-dummy) test equipment usually more than compensates for the fluid weight loss, and the vehicle generally is slightly heavier than the test weight. Therefore, other weight must be removed until the test weight is reestablished.

Please note that NHTSA will remove parts of the vehicle to compensate for the weight of the test equipment only as a last resort. The agency will first remove cargo or luggage ballast. If still more weight must be removed (i.e., in the unlikely event that the weight of the test equipment exceeds the weight of the removable cargo and luggage) the agency will remove parts of the vehicle. This is only likely to occur in vehicles with very small cargo capacities, such as sports cars. In this event, NHTSA would remove only parts of the car that play no part in the side impact test (e.g. bumpers).

You next ask about the "vehicle test attitude" specifications of S6.2. By way of background, NHTSA determines the attitude of the vehicle in its "as delivered" condition (i.e., the vehicle as received at the test site, filled to 100 percent of all fluid capacities and with all tires inflated to the manufacturer's specifications) and in its "fully loaded condition," under the vehicle test attitude specification of S6.2. Under S6.2, the vehicle's pretest attitude is equal to either the as delivered or the "fully loaded attitude" or between the as delivered and the fully loaded attitude.

You ask whether the term "fully loaded attitude" means the attitude of the vehicle in the "fully loaded condition." The answer is yes. Moreover, S6.2 specifies that "[t]he `fully loaded condition' is the test vehicle loaded in accordance with S6.1." As mentioned in our response to your first question, S6.1 explains how to load the vehicle to achieve the test weight.

You also ask whether the "as delivered" left-to-right attitude must be maintained when adding test equipment. The answer is also found in S6.2's specification that "[t]he pretest vehicle attitude is equal to either the as delivered or fully loaded attitude, or between the as delivered attitude and the fully loaded attitude." This language describes a range of attitudes, including the left-to-right attitude, which the vehicle may be in at the time of the test. The vehicle must be capable of passing the test anywhere within the prescribed range. Therefore, when NHTSA tests a vehicle, the agency has leeway in maintaining the as delivered left- to-right attitude when adding test equipment. As long as the left-to-right attitude after adding equipment is somewhere between the attitude in the as delivered condition and the fully loaded condition, an acceptable pretest vehicle attitude will be achieved.

Finally, I would like to note that NHTSA's Enforcement Office prepares updates to its laboratory test procedures on an as-required basis. The updates include rule changes and maintenance revisions. We project a maintenance update to the side impact test procedures (TP-214D-03) will be published within the next six months. During this update, issues addressed in this letter will be considered.

I hope you find this information helpful. If you have any other questions, please contact Ms. Deirdre Fujita of my staff at (202) 366-2992.

Sincerely,

John G. Womack Acting Chief Counsel

ref:214 d:6/28/94

ID: 9211

Mr. Randolph Schwarz
141 North Madison Drive
South Plainfield, NJ 07080

Dear Mr. Schwarz:

This responds to your letter to Mr. John Messera of NHTSA, requesting an interpretation of Federal Motor Vehicle Safety Standard No. 116; Motor vehicle brake fluids. Your letter has been referred to my office for a response. As a consumer retrofitting your vehicle with DOT 5 brake fluid, you had several questions concerning the possible effects that an ingredient in the brake fluid might have on elastomers used in brake systems. Your questions are answered below.

You mentioned "seal swelling additives" added to DOT 5 brake fluid, that contact various elastomers in the brake system. Your first question was, when brake fluid manufacturers combine additives with brake fluid, should consumers be concerned with the combined fluids' compatibility with various elastomers used in braking systems?

Standard No. 116 defines, at S4. Definitions, brake fluid as a liquid designed for use in a motor vehicle hydraulic brake system where it will contact elastomeric components made of: styrene and butadiene rubber (SBR); ethylene and propylene rubber (EPR); polychlorophene (CR) brake hose inner tube stock; or natural rubber (NR). In order to minimize failures in hydraulic braking systems, Standard No. 116 specifies minimum performance standards for brake fluids. These performance standards include tests for styrene and butadiene rubber cups, the most common type of elastomer in a hydraulic brake system. The brake fluid manufacturer must certify that the brake fluid complies with Standard No. 116. (See S5.2.2(d).) While DOT 5 brake fluid must meet Standard No. 116, the specific ingredients in the fluid are not regulated by the standard.

The brake fluid manufacturer is expected to be aware that in addition to SBR, its brake fluid may contact EPR, CR, and NR elastomers in the brake system. Thus, the brake fluid manufacturers must ensure that contact between the fluid and the above stated elastomers would not result in a safety- related defect under the National Traffic and Motor Vehicle Safety Act. Sections 151-159 of the Safety Act concern the recall and remedy of products with defects related to motor vehicle safety. In the event that the brake fluid manufacturer or NHTSA determines that the brake fluid contains a safety related defect, the brake fluid manufacturer would be responsible for notifying purchasers of the defective brake fluid and remedying the problem free of charge.

Your second question was whether DOT 5 brake fluid's compliance with Standard No. 116 ensures compatibility with elastomers. The answer is yes, for SBR elastomers. Further, besides Standard No. 116, the brake fluid manufacturer is subject to sections 151-159 of the Safety Act, that were previously discussed. At this time, NHTSA is not aware of safety related defects resulting from other ingredients used with brake fluid.

Your third question was whether Standard No. 116 only addresses SBR compatibility with brake fluid. Standard No. 116, at S4, addresses brake fluid that contacts four elastomer types. However, the tests specified in the standard are only of the most commonly used SBR cups.

Your fourth question was, if Standard No. 116 only mentions SBR elastomer, would it be advisable to add other elastomers to the specification, or to discuss elastomer compatibility on the brake fluid container?

Information discussing the elastomer compatibility of the brake fluid, or other ingredients, may be voluntarily placed on brake fluid containers. Standard No. 116 specifies information that brake fluid containers must carry. However, Standard No. 116 does not prohibit manufacturers from noting on brake fluid containers, compatibility of the silicone brake fluid, or other ingredients, with various elastomers.

Finally, you asked what Standard No. 116 specifies as the maximum viscosity for DOT 5 brake fluid, at -40 degrees Fahrenheit. Standard No. 116 specifies, at S5.1.3(c), that the maximum viscosity is 900 centistokes (cSt).

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

Sincerely,

John Womack Acting Chief Counsel

ref:116 d:5/5/94

ID: 9217

Mr. Jason Backs
Engineering Department
Travis Body and Trailer, Inc.
13995 F.M. 529
Houston, TX 77041

Dear Mr. Backs:

We have received your FAX of October 19, 1993, to Taylor Vinson of this Office, asking for an interpretation of the trailer conspicuity requirements of Federal Motor Vehicle Safety Standard No. 108 as it applies to a dump trailer manufactured by your company.

With respect to the location of the horizontal side conspicuity treatment, you prefer not to place it on the rubrail because "our present extrusions have raised ridges on the outer surface." You propose to apply the conspicuity treatment between each side stake, resulting in 58% coverage of the trailer side. The tape is "in full view" from a point perpendicular to the side of the trailer, but at approximately 30 degrees from perpendicular, the edge of the tape begins to be obstructed by the side stake. You ask for our concurrence that your proposed treatment is in accordance with Standard No. 108.

We are pleased to provide our concurrence. The mounting height requirements of Paragraph S5.7.1.4.2 are specified in terms of practicability. The rule was amended on October 6, 1993, to specify a mounting height of "as close as practicable to not less than 375 mm and not more than 1525 mm above the road surface." The determination of practicability, in the first instance, is that of the manufacturer certifying compliance with Standard No. 108. NHTSA will not question that determination unless it appears clearly erroneous. Because of raised ridges, you deem the rubrail not as practicable a location as the slightly higher area. Paragraph S5.7.1.4.2 allows discontinuities in the side treatment as long as not less than half the side is covered and the spaces are distributed as evenly as practicable.

Although the sheeting itself must meet the performance indicated at the observation angles specified in Figure 29, there are no visibility requirements that apply to it once it is installed on a trailer. This mean that the obscuring of the conspicuity treatment that begins at about 30 degrees from perpendicular under your proposed treatment is not prohibited by Standard No. 108.

Sincerely,

John Womack Acting Chief Counsel

ref:108 d:11/18/93

ID: 9219

Mr. Frank Williams
President
Safety Brake Set
3508 Cascade Highway
Silverton, OR 97381

Dear Mr. Williams:

This responds to your letter requesting information about Federal requirements related to a product that "sets the brakes on an air brake vehicle when the driver exits the cab." I apologize for the delay in our response. You stated that your "device does not hook into the brake system but pops the parking button out if the driver is off the seat and the door is open. The brake then must be manually disengaged." You requested confirmation that the agency will neither support nor oppose the aftermarket installation of such a device.

I am pleased to have this opportunity to explain our regulations to you. I am also enclosing a copy of a fact sheet entitled "Information for New Manufacturers of Motor Vehicles and Motor Vehicle Equipment."

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

NHTSA does not have any specific regulations about a product such as your device. However, since this device is related to a vehicle's air brake system, it could affect a vehicle's compliance with Standard No. 121, Air Brake Systems. That standard applies to almost all new trucks, buses, and trailers equipped with air brake systems.

If your system is installed as original equipment on a new vehicle, the vehicle manufacturer is required to certify that, with the device installed, the vehicle satisfies the requirements of all applicable safety standards, including Standard No. 121. (See 15 U.S.C. 1397(a)(1) and 49 CFR Part 567). If the device is added to a previously certified new motor vehicle prior to its first consumer purchase, then the person who modifies the vehicle would be an alterer of a previously certified motor vehicle and would be required to certify that, as altered, the vehicle continues to comply with all of the safety standards affected by the alteration. 49 CFR 567.7.

If the device is installed on a used vehicle by a manufacturer, distributor, dealer, or motor vehicle repair business, then the installer would not be required to attach a certification label. However, it would have to make sure that it did not knowingly render inoperative, in whole or in part, any device or element of design installed on or in a motor vehicle or item of motor vehicle equipment in compliance with an applicable Federal motor vehicle safety standard. 15 U.S.C. 1397(a)(2)(A). In particular, these entities should ensure that the installation of your device does not render inoperative the vehicle's compliance with the parking brake requirements set forth in S5.6.

I hope this information is helpful. If you have any questions about NHTSA's safety standards, please feel free to contact Marvin Shaw at this address or by telephone at (202) 366-2992.

Sincerely,

John Womack Acting Chief Counsel

Enclosure ref:121 d:4/21/94

ID: 9220

Ms. Amantha L. Barbee
Sales Coordinator
Thomas Built Buses, Inc.
Post Office Box 2450
High Point, NC 27261

Dear Ms. Barbee:

This responds to your letter to me of October 14, 1993, and your telephone conversation with Walter Myers of my staff on October 22, 1993.

You stated in your letter that you are the Head Start Sales Coordinator for Thomas Built Buses, Inc., and in that capacity you have found that many Head Start agencies are using conventional vans to transport Head Start students to and from their programs. You stated that when you asked the directors of the agencies why they did not use vehicles that comply with Federal motor vehicle safety standards (FMVSS) for school buses, their usual answer was "because we have not been told otherwise." You then asked whether this practice is illegal and if so, what your organization can do to rectify the situation.

As Mr. Myers explained in your telephone conversation, this agency has repeatedly stated that Head Start facilities are preprimary schools. Therefore, new buses sold to Head Start centers for use in transporting Head Start participants to and from school must comply with all Federal motor vehicle safety standards applicable to school buses. However, Federal law does not require Head Start facilities to use complying school buses or any other particular vehicles. The individual states, not the Federal government, have authority over the use of vehicles.

As promised by Mr. Myers, please find enclosed interpretation letters previously issued by us on this issue, as follows: to Hon. Paul David Wellstone, U.S. Senate, dated Jan. 26, 1993; to Mr. Chuck Anderson, dated Aug. 21, 1992; and to Mr. Charles Pekow, dated Sept. 27, 1985.

I hope this information will be useful. If you have any further questions or desire any further information, please feel free to contact Mr. Myers at this address or at (202) 366-2992.

Sincerely,

John Womack Acting Chief Counsel Enclosures

ref:571#102 d:11/23/93

ID: 9226

Mr. J. C. DeLaney
Manager, Technical Programs
Motorcycle Industry Council, Inc.
2 Jenner Street, Suite 150
Irvine, CA 92718-3812

Dear Mr. DeLaney:

This responds to your request for an interpretation of Federal Motor Vehicle Safety Standard No. 123; Motorcycle controls and displays. You asked whether a motorcycle side stand complies with Standard No. 123 if the stand passes SAE J1587 Motorcycle Side Stand Retraction Test Procedure.

Standard No. 123 specifies at S5.2.4 Stands that: "A stand shall fold rearward and upward if it contacts the ground when the motorcycle is moving forward." Neither S5.2.4 nor any other provision of Standard No. 123 incorporates by reference, SAE J1587. Thus, if a motorcycle side stand passes the SAE J1587 test procedure, it does not automatically follow that the side stand complies with Standard No. 123.

I hope that this information is useful. If you have any further questions, please contact Dorothy Nakama of my staff at (202) 366-2992.

Sincerely,

John Womack Acting Chief Counsel ref:123 d:11/23/93

ID: 9229

Mr. Donald W. Vierimaa
Vice President-Engineering
Truck Trailer Manufacturers Association
1020 Princess Street
Alexandria, VA 22314

Dear Mr. Vierimaa:

This responds to your letter of October 19, 1993, with respect to the trailer conspicuity requirements of Standard No. 108.

You report that "[o]ften a new tank trailer will be sold to a customer who will contract with another party to have a lining installed in the tank." Because of the high heat used in the installation of the lining, retroreflective sheeting cannot be applied before the lining is installed.

We believe that the trailer manufacturer is a more appropriate person for ensuring that its product meets the conspicuity requirements of Standard No. 108 than the installer of the lining, or the owner of the trailer. We would like to suggest alternative methods of compliance, other than a direct application of retroreflective tape to the trailer sides, as a resolution of this problem. Standard No. 108 permits the use of reflex reflectors as an alternative to retroreflective sheeting. If the trailer manufacturer prefers retroreflective sheeting, the sheeting may be applied at a lower level if deemed "practicable", or it may be applied to horizontal strips of aluminum that can be fastened to the sides of tank trailers and removed during the installation of the lining.

You also state that "non-tank trailers may be sold without conspicuity treatment when the owner wishes to contract the application of special paint and logo schemes." Sale of a trailer under these circumstances, without its compliance with the conspicuity requirements of Standard No. 108, would be an apparent violation of the National Traffic and Motor Vehicle Safety Act.

Sincerely,

John Womack Acting Chief Counsel ref:108 d:11/22/93