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Interpretation ID: aiam5238

Mr. Sam C. Nigro Bus Product Manager Webasto Thermosystems 1598 E. Lincoln Madison Heights, MI 48071; Mr. Sam C. Nigro Bus Product Manager Webasto Thermosystems 1598 E. Lincoln Madison Heights
MI 48071;

"Dear Mr. Nigro: This responds to your letter about auxiliary heater fueled by compressed natural gas (CNG) and liquid natural gas (LNG) for installation on buses using those alternative fuels. You stated that your company currently manufactures auxiliary heaters for diesel fueled buses, and is interested in developing heaters that would 'burn CNG and LNG same as the engine.' In a telephone conversation with Marvin Shaw of my staff, you explained that you would like information about NHTSA's current requirements for auxiliary heaters on alternative fueled buses and the agency's future plans in this area. I am pleased to have this opportunity to explain our regulations to you. By way of background information, NHTSA does not provide approvals of motor vehicles or motor vehicle equipment. Under the National Traffic and Motor Vehicle Safety Act (Safety Act, 15 U.S.C. 1381, et seq.), it is the responsibility of the manufacturer to ensure that its motor vehicles or equipment comply with applicable Federal motor vehicle safety standards (FMVSS's). The following represents our opinion based on the facts provided in your letter. NHTSA does not have any safety standards specifically covering auxiliary heaters of any kind, and I am not aware of any plans to issue standards in this area. Nevertheless, an auxiliary heater is an item of motor vehicle equipment. As a manufacturer of motor vehicle equipment, you are subject to the requirements in 151-159 of the Safety Act concerning the recall and remedy of products with defects relating to motor vehicle safety. If you or NHTSA determines that a safety-related defect exists, you must notify purchasers of your product and remedy the problem free of charge. (This responsibility is borne by the vehicle manufacturer in cases in which the heater is installed on a new vehicle by or with the express authorization of that vehicle manufacturer.) Any manufacturer that fails to provide notification of or remedy for a defect may be subject to a civil penalty of up to $1,000 per violation. As Mr. Shaw informed you on the telephone, earlier this year NHTSA proposed to issue a safety standard that would apply to CNG tanks (i.e., containers designed to store CNG as motor vehicle fuel on-board a motor vehicle) and vehicles using CNG as a fuel (58 FR 5323, January 21, 1993). If this proposed standard is adopted, it would affect your product in the following manner. If your heater were installed as original equipment on a new vehicle, the vehicle manufacturer is required by our certification regulations to certify that the entire vehicle (with your product installed) satisfies the requirements of all applicable FMVSS's, including the CNG fuel system standard. If the heater were added to a new, previously-certified vehicle (e.g., a new completed bus), the person who adds the system would be required to certify that, as altered, the vehicle continues to comply with all of the safety standards affected by the alteration. These certification requirements apply to the vehicle manufacturer and alterer regardless of whether the heater is connected to the vehicle's fuel system. Of course, if the heater is connected to the vehicle's fuel system, the vehicle's compliance with the CNG standard should be carefully scrutinized. If the heater were installed on a used vehicle by a vehicle manufacturer, distributor, dealer or repair business, the installer would not be subject to the certification requirements outlined above. Instead, the installer would have to ensure that it did not knowingly render inoperative the compliance of the vehicle with any applicable safety standard, including the CNG standard. This is required by 108(a)(2)(A) of the Safety Act. If the modification of the vehicle entailed connecting the heater to the vehicle's fuel system, compliance with the CNG standard would be especially germane to whether 108(a)(2)(A) were violated. The prohibition of 108(a(2)(A) does not apply to individual vehicle owners who alter their own vehicles. Thus, under our requirements, individual owners may install any item of motor vehicle equipment regardless of its effect on compliance with the FMVSS's. However, NHTSA encourages vehicle owners not to tamper with vehicle safety equipment if the modification would degrade the safety of the vehicle. The certification responsibilities discussed above would affect vehicle manufacturers even if the proposed CNG standard is not adopted or is not yet effective when you market your product. Except for FMVSS 301, which sets fuel system integrity requirements for gasoline and diesel-powered buses under 10,000 pounds GVWR, all of the FMVSS's that apply to a diesel- or gasoline-powered vehicle now apply to a CNG-powered vehicle. A manufacturer of a CNG-powered vehicle who installs your heater as original equipment must certify the vehicle to those standards, regardless if the CNG FMVSS is among them. Similarly, a vehicle alterer would have to certify that the vehicle, as altered, complies with all applicable FMVSS's. The 'render inoperative' prohibition would also apply even in the absence of a CNG FMVSS. The commercial entity listed in 108(a)(2)(A) who installs the heater on a CNG-powered vehicle would have to ensure that it did not knowingly render inoperative the compliance of the vehicle with any FMVSS that applies to the vehicle, even if a CNG standard is not among them. I am enclosing for your information a copy of NHTSA's proposed FMVSS for CNG tanks and vehicles. Also enclosed is a fact sheet titled Information for New Manufacturers of Motor Vehicles and Motor Vehicle Equipment, and a booklet entitled Federal Motor Vehicle Safety Standards and Regulations. As you are aware, the Federal Highway Administration has issued a regulation applicable to heaters on commercial vehicles. (49 CFR 393.77). You can contact the FHWA for an interpretation of its regulations at the following address: Theodore McConnell Chief Counsel Federal Highway Administration 400 7th Street, SW Washington, D.C. 20590 I hope this information is helpful. Please feel free to contact Marvin Shaw at this address or by telephone at (202) 366-2992 if you have any further questions or need additional information. Sincerely, John Womack Acting Chief Counsel Enclosure";