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Interpretation ID: nht79-3.14

DATE: 08/14/79

FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA

TO: Mr. D. J. Arneson

TITLE: FMVSS INTERPRETATION

TEXT: This is in response to your letter of June 27, 1979, which inquired whether there are any regulations governing the installation of a propane-fueled engine, or the conversion of a gasoline-fueled engine to a propane-fueled engine, in vehicles registered for use on Federal, State, and local highways.

To date, the National Highway Traffic Safety Administration (NHTSA) has not exercised its authority pursuant to the National Traffic and Motor Vehicle Safety Act, as amended 1974 (15 U.S.C. 1381 et seq.) (the Act), to issue a safety standard applicable to propane-powered vehicles. Federal Motor Vehicle Safety Standard No. 301-75, Fuel System Integrity, applies only to vehicles which use fuel with a boiling point above 32 degrees F., and propane has a boiling point well below this temperature. Despite the absence of safety standards specifically applicable to propane-powered engines, however, an installer of these systems may be subject to other Federal requirements.

Under NHTSA safety regulations, a person who alters a new vehicle prior to its first purchase in good faith for purposes other than resale is required to attach an additional label to the vehicle certifying that, as altered, the vehicle remains in compliance with all applicable safety standards (49 CFR 567.7). This requirement would apply to a person who alters a new vehicle to install a propane fuel system. (See the enclosed pamphlet listing the Federal motor vehicle safety standards and an information sheet explaining where to obtain copies of the standards.) Additionally, should a noncompliance or safety-related defect be discovered in such a vehicle, as a result of the modification, the alterer could be liable for a civil penalty unless he or she could establish that he or she did not have actual knowledge of the noncompliance and that he or she did not have reason to know in the exercise of due care that the vehicle did not comply. (Section 108 (b)(2)) Defects in the propane-fueled engines or in components used for converting a gasoline-fueled engine would be the responsibility of their manufacturers, regardless of whether they were installed in new or used vehicles. Upon discovery of a safety-related defect by either the Secretary of Transportation, the NHTSA Administrator or the manufacturer himself, the manufacturer would be required to notify vehicle owners, purchasers, and dealers and provide a remedy for the defect.

A person who installs a propane-fueled engine or converts the gasoline-fueled engine in a used vehicle is not required to affix an alterer's label. However, if that person is a manufacturer, distributor, dealer, or motor vehicle repair business, he must not in the course of installing the propane components knowingly render inoperative any device or element of design originally installed in the vehicle in compliance with applicable Federal motor vehicle safety standards. (Section 108(a)(2)(A) of the Act)

I hope that you will find this response helpful and have not been inconvenienced by our delay in sending it to you.

SINCERELY,

Information Officer U.S. Dept. of Transportation

June 27, 1979

Dear Sir,

Please send me a complete set of regulations governing the installation or conversion of a gasoline fueled engine to a propane fueled engine for use in registered vehicles on federal, state and local highways, if any.

If there are no regulations governing such a conversion, please inform me.

D. J. Arneson