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Interpretation ID: 2839yy

The Honorable John D. Dingell
Chairman, Subcommittee on Oversight
and Investigations
Committee on Energy and Commerce
House of Representatives
Washington, DC 20515

Dear Mr. Chairman:

Your letter of July 10, 1990 about the applicability of NHTSA's safety standards to replacement parts was misplaced. This is indeed unfortunate, embarrassing, and I can assure you extraordinary. You asked me to review an April 9, 1990 interpretation letter from our Office of Chief Counsel to Mr. Rowghani, which indicated that Standard No. 214, Side Door Strength, applies only to new vehicles, and not to doors sold as replacement parts.

In view of your concern about replacement parts, we have reviewed that interpretation, and our authority regarding replacement parts. Many of our safety standards apply only to complete vehicles, while others apply only to the individual components (whether original or replacement equipment). Some apply both to vehicles and to the components involved. Each of our standards includes an "Application" section, which clearly defines the scope of coverage, based on the nature of the safety issue and the vehicle/equipment items involved.

NHTSA's standards which apply to equipment (both original and replacement equipment) generally cover those types of items which can be used in many different vehicle lines, which are frequently replaced or sold separately, and which can be independently tested. These include such items as brake hoses (Standard 106), lamps and reflectors (Standard 108), tires (Standards 109, 117 and 119), windows and windshields (Standard 205), safety belt assemblies (Standard 209), child safety seats (Standard 213), and motorcycle safety helmets (Standard 218). Other safety systems require testing in a full-vehicle context, and our safety standards are applied to the vehicle rather than the component. Examples include brake performance (Standards 105 and 121), occupant crash protection (Standard 208), head restraints (Standard 202) and roof-crush resistance (Standard 216), as well as side-door strength.

As noted in the April 9 letter, Standard 214 applies only to whole cars, not to replacement parts, as stated in the application section (see S2 of Standard 214, copy enclosed). While most manufacturers have chosen to meet the Standard by adding reinforcement beams, we are aware of at least one vehicle (a gray-market imported Mercedes-Benz) which passed the standard's compliance test without such a beam. Further, while intuitively it seems that doors without a reinforcement beam are not as safe as ones with a beam, efforts to document a safety problem have been unsuccessful.

The current compliance procedures specify testing a door as part of a new vehicle (see S4 of Standard 214), since it does not appear feasible to specify an appropriate procedure for testing an individual new door (whether original or replacement) by itself. The reason for this is that a door's performance in resisting intrusion is dependent not only on the structure of the door itself, but also other factors such as the vehicle frame into which the door fits, and the hinges and latches which hold the door in place within the frame. In addition, vehicle seats may help resist intrusion and protect occupants. The current standard reflects these factors.

While the current standard does not apply to replacement doors, NHTSA has full authority to pursue any alleged safety problems with doors or any other vehicle components under the "defects" provision of the Safety Act. If evidence demonstrated that certain replacement doors presented an unreasonable risk to motor vehicle safety, the agency could order the manufacturer of such doors to repair or replace such doors. At the present time, however, we are not aware of a safety problem with replacement doors that would warrant the commencement of a defects investigation.

I appreciate your interest in the safety of vehicle parts and hope this information is helpful. For further discussion of the legal issues regarding the applicability of standards, your staff should feel free to contact our Chief Counsel, Mr. Paul Jackson Rice, at 366-9511.

Sincerely,

Jerry Ralph Curry

Enclosure /ref:214 d:2/l5/9l