Interpretation ID: aiam3027
Chief of Specifications
State Board of Control
111 East 17th Street
Austin
TX 78711;
Dear Mr. Martin: This confirms your May 23, 1979, conversation with Roger Tilton of m staff in which you asked whether it is permissible for vehicles to be modified by the addition of propane gas systems replacing their regular fuel systems.; As Mr. Tilton stated, the National Highway Traffic Safet Administration permits the type of modification mentioned above. If the modification is done to a new vehicle, the person making the modification would be required to attach an alterer's label in accordance with Part 567.7, *Certification*, of our regulations. That label states that the vehicle, *as altered*, continues to comply with all safety standards. The standard that may be affected by such a modification would be Standard No. 301, *Fuel System Integrity*. If used vehicles are being modified, the person modifying the vehicle would not be required to attach a label. However, that person would be responsible for noncompliance with safety standards if he or she knowingly rendered inoperative any element of design installed in or on the vehicle in compliance with a safety standard.; Sincerely, Frank Berndt, Chief Counsel