Interpretation ID: 86-3.8
TYPE: INTERPRETATION-NHTSA
DATE: 05/02/86
FROM: AUTHOR UNAVAILABLE; Erika Z. Jones; NHTSA
TO: E. Brooks Harper -- General Manager, Backstop, Inc.
TITLE: FMVSS INTERPRETATION
TEXT:
Mr. E. Brooks Harper General Manager Backstop, Inc. 240 Pegasus Avenue Northvale, NJ 07647
This responds to your letter asking whether installation of your touch sensitive reverse braking system called "Backstop" on an air brake vehicle would conflict with any Federal motor vehicle safety standards or regulations. According to your letter, Backstop is plumbed into the vehicle air brake system and wired to the back up light circuit. The system is activated only when reverse gear is engaged and works by instantly applying the vehicle brakes when the rear bumper is touched while reversing. Shifting to neutral or a forward gear returns the system to normal braking.
By way of background information, the National Highway Traffic Safety Administration (NHTSA) does not provide approvals of motor vehicles or motor vehicle equipment. The National Traffic and Motor Vehicle Safety Act places the responsibility on the manufacturer to certify that its vehicles or equipment comply with applicable requirements. The following represents our opinion based on the facts provided in your letter and is limited to the standards and regulations administered by NHTSA. You may wish to contact the Bureau of Motor Carrier Safety (BMCS) concerning whether any of its regulations are relevant to the installation of Backstop.
NHTSA does not have any regulations covering a touch sensitive reverse braking system such as Backstop. However, since installation of Backstop requires plumbing into the vehicle's air brake system and wiring into the vehicle's backup light circuit, it is possible that it could affect a vehicle's compliance with Federal Motor Vehicle Safety Standards (FMVSS) No. 121, Air Brake Systems, and Ko. 108, Lamps( reflective devices, and associated equipment. For example, your letter states that a delay of four milliseconds is introduced to the air brake system response by the insertion of the double check valve in the control line. While this delay is very small, it could conceivably affect a vehicle's compliance with the timing requirements of sections S5.3.3 and S5.3.4 of FMVSS No. 121 if the vehicle otherwise was at the edge of compliance. He suggest that you carefully consider whether installation of Backstop in the variety of current vehicles and vehicle configurations would affect compliance with the requirements or FMVSS No. 121 or any other Federal motor vehicle safety standard.
If your device is added to a new motor vehicle prior to its first sale, the person who modified 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 the safety standards affected by the alteration. The specific certification requirements for alterers are set forth at 49 CFR Part 567.7, Certification. On the other hand, you as the manufacturer of Backstop would have no certification responsibilities, because we have no safety standards applicable to your equipment. However, an alterer would probably require information from you in order to make the necessary certification.
If your device is installed on a used vehicle by a business such as a garage, the installer would not be required to attach a certification label. However, it would have to make sure that it did not knowingly render inoperative the compliance of the vehicle with any safety standard. This in required by section 108(a)(2)(A) of the National Traffic and Motor Vehicle Safety Act.
Should a safety-related defect be discovered in your device, whether by the agency or yourself, you as the manufacturer would be required under sections 151 et seq. of the Act to notify vehicle owners, purchasers, and dealers and provide a remedy for the defect.
Sincerely,
Original Signed By
Erika Z. Jones Chief Counsel
December 3, 1985
Ms. Erika Jones/Chief Counsel National Highway Traffic Safety Administration 400 Seventh Street, S. W. Washington, D.C. 20590
Dear Ms. Jones:
The purpose of this letter is to request an interpretation as to whether or not the installation of a BACKSTOP system on an air brake vehicle would conflict with any federal motor vehicle safety standards or regulations.
BACKSTOP is s touch sensitive reverse braking system for air brake vehicles. It is marketed to truck, bus, and other heavy vehicle operators for the purpose of increasing safety and reducing property damage (see enclosed brochure).
BACKSTOP is plumbed into the vehicle air brake system and wired to the back up light circuit according to the enclosed diagram. The BACKSTOP system is activated only when reverse gear is engaged and works by instantly applying the vehicle brakes when the rear bumper is touched while reversing. Shifting to neutral or a forward gear returns the system to normal braking.
Our tests show that an insignificant delay of four (C) milliseconds is introduced to the air brake system response by the insertion of the double check valve in the control line (refer to enclosed test data). Failure of the BACKSTOP system in any way would not compromise the normal performance of the vehicles original air brake system.
Based on the tests we have performed, discussions with vehicle manufacturer brake system engineers, and our known knowledge of air brake systems, we state that installation of the BACKSTOP system on an air brake vehicle does not degrade that vehicles' compliance with any applicable federal motor vehicle safety standards or regulations.
We request that your office acknowledge our position pith respect to installation of the BACKSTOP system on air brake vehicles.
Thank you for your consideration.
Sincerely,
BACKSTOP INC.
E. Brooks Harper General Manager
EBH/gm Enclosure
cc: Mr. Duane E. Perrin/NHTSA
November 15, 1985
45 BUDD TRAILER
SEALCO VALVES 30" BRAKE CHAMBERS AUTOMATIC SLACK ADJUSTERS
TEMPERATURE 54 SUPPLY PSI 120 SERVICE CHAMBER PSI 60 ----------------------------------------------------------------TO TEST EFFECT OF TWO WAY CHECK VALVE IN SERVICE LINE OF AIR BRAKE SYSTEM ----------------------------------------------------------------
TWO 2400 CUBIC INCH TANKS -ONE ON SERVICE, ONE ON SUPPLY. BOTH AT 120 PSI. THREE WAY AIR SOLENOID ON SERVICE WITH AN ON SWITCH TO START CLOCK AND OPEN TANK. A SHUT OFF SWITCH ON SERVICE CHAMBER WHEN 60 PSI IS REACHED TO SHUT OFF CLOCK.
WITH VALVE IN SERVICE LINE WITH NO VALVE IN SERVICE LINE
293 288
293 290
293 291
293 292
294 290
294 290
293 288
293 287 ----------------- 2346 2316 Average -293.25 ms. Average 289.5 ms.