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Interpretation ID: nht93-6.10

DATE: August 13, 1993

FROM: John Womack -- Acting Chief Counsel, NHTSA

TO: Alan Niedzwiecki -- Director of Business Development, EDO Corporation

TITLE: None

ATTACHMT: Attached to letter dated 6/22/93 from Alan Niedzwiecki to John Womack

TEXT:

This responds to your letter requesting information about this agency's activities related to cylinders for "compressed natural gas (CNG) vehicle on-board motor fuel storage." According to your letter, EDO is developing an all-composite cylinder that has a safety factor of 3.5. You further explained that your company is planning to begin a conversion program using these cylinders.

Mr. Marvin Shaw of my staff discussed your letter with your associate, Mr. John Vincenzo. Mr. Vincenzo said that EDO knows that the National Highway Traffic Safety Administration (NHTSA) is conducting a rulemaking related to CNG cylinders. Mr. Vincenzo seeks confirmation that, until a rule results from that rulemaking, there is no Department of Transportation regulation with which your company is required to comply before you start your conversion program.

By way of background information, NHTSA is authorized under the National Traffic and Motor Vehicle Safety Act (15 U.S.C. S1381 et seq.; Safety Act) to issue Federal motor vehicle safety standards that set performance requirements for new motor vehicles and items of motor vehicle equipment. NHTSA does not, however, approve or certify any vehicles or items of equipment. Instead, the Safety Act establishes a "self-certification" process under which each manufacturer is responsible for certifying that its products meet all applicable safety standards. NHTSA also investigates safety-related defects in motor vehicles and items of motor vehicle equipment.

At present, NHTSA has not issued any standard applicable to CNG cylinders or any regulation dealing with the conversion of vehicles to be equipped with such cylinders. Therefore, until such time as a standard is issued, you are correct that you are not required to comply with any NHTSA safety standard related to CNG fuel systems.

However, please be aware that manufacturers of CNG tanks and vehicles are subject to the requirements in sections 151-159 of the Safety Act concerning the recall and remedy of products with defects related to motor vehicle safety. In the event that NHTSA or the manufacturer of the tank or vehicle 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.

In addition, NHTSA has certain restrictions on vehicle fuel system conversions, depending on who does the conversion and when the work is done. I have enclosed a discussion that sets forth the implications under our present regulations of converting new and used gasoline-powered vehicles to use propane or other gas (such as CNG). That discussion addresses NHTSA's vehicle alterer requirements (49 CFR S567.7) which apply to work on new vehicles, and the Safety Act's "render inoperative" provision (S 108(a)(2)(A)), which applies to

work on new and used vehicles. Section 108(a)(2)(A) prohibits vehicle manufacturers, distributors, dealers and repair businesses from "knowingly rendering inoperative, in whole or in part, any device or element of design installed ... in compliance" with any FMVSS. Please contact us if you have further questions relating to the enclosed discussion.

I also note that the enclosed discussion is based on the FMVSS's that are currently in effect. As you know, NHTSA issued a proposed rule for CNG tanks and vehicles using CNG as a fuel. (58 FR 5323, January 21, 1993). If the agency were to ultimately decide to adopt the proposal, it would be necessary for NHTSA to revisit the "render inoperative" issues that relate to vehicle conversions. For example, if NHTSA were to issue a safety standard for CNG cylinders, all cylinders manufactured after the effective date of the standard would be required to comply with its requirements, whether they are placed on new vehicles or on new or used vehicles converted to CNG fuel.

With regard to present requirements for vehicle conversions, you should also note that the Federal Highway Administration (FHWA) of this Department has operational and equipment requirements for commercial vehicles used in interstate commerce. For information about possible FHWA requirements affecting your conversions, you can contact that agency's Chief Counsel's office at (202) 366-0650.

You were particularly interested in NHTSA's proposed rule for CNG tanks and vehicles using CNG as a fuel. In response to that proposal, the agency received over 55 comments (including one from your corporation), which we are currently analyzing. We expect our next regulatory decision in early 1994. In addition, please be aware that the January 1993 notice was a proposal and does not necessarily reflect the precise requirements that will be contained in the final rule.

I hope you find this information helpful. If you have any other questions, please contact Marvin Shaw at this address or by phone at (202) 366-2992.