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Interpretation ID: 86-6.12

TYPE: INTERPRETATION-NHTSA

DATE: 12/15/86

FROM: AUTHOR UNAVAILABLE; Erika Z. Jones; NHTSA

TO: Adam Humes -- General Manager, Marquis Coachcrafters

TITLE: FMVSS INTERPRETATION

TEXT: Thank you for your letter to Stephen Oesch of my office concerning the effect of our regulations on the conversion of hardtop vehicles into convertibles. You explained that your company will be performing such conversions on new Cadillac Sedan De Villes and you are specifically concerned about how Standards No. 208, Occupant Crash Protection, and Standard No. 209, Seat Belt Assemblies, would affect such conversions. I regret the delay in our response.

Under the National Traffic and Motor Vehicle Safety Act, each manufacturer is required to certify that its vehicles comply with all applicable Federal Motor Vehicle Safety Standards. Under Part 567.7 of the agency's certification regulation, a copy of which is enclosed, a person who alters a new vehicle prior to its first sale to the consumer must certify that the vehicle, as altered, still conforms with all applicable standards. Thus, your company would have to certify that the vehicle you have altered into a convertible still complies with all applicable standards.

In the case of Standard No. 208, S4.1.2.3.2 of the standard permits convertibles to have either a lap or lap/shoulder belt at each front outboard designated seating position. Thus, when you alter a hardtop passenger car, you may remove the lap/shoulder belt and replace it with a lap belt that meets the requirements of S4.1.2.3.2.

Please note that beginning on September 1, 1986, manufacturers must begin phasing-in the installation of automatic restraint systems, such as automatic belts and airbag systems, in their vehicles. For example, S4.1.3.1 of Standard No. 208 requires manufacturers to install automatic restraints in ten percent of their passenger cars manufactured on or after September 1, 1986, and before September 1, 1987. The agency has temporarily excluded convertibles from the automatic restraint requirement during the phase-in period. Instead of automatic restraints, convertibles may have either a manual lap or lap/shoulder belt.

Please note that the agency's final decision in the ongoing rulemaking on applying the automatic restraint requirement to convertibles may affect the conversion of hard-top cars into convertibles in subsequent years. If the agency does not exempt convertibles permanently from the automatic restraint requirement, then a person changing an automatic restraint equipped hardtop car into a convertible would have to ensure that the altered cars still complied with the automatic restraint requirement. Likewise, if the agency applied a dynamic test requirement to the manual safety belts used in convertibles, a person altering an automatic restraint equipped hardtop car into a convertible would have to either retain the automatic restraints or equip the altered vehicles with manual safety belts meeting the dynamic test requirements.

If you have any further questions, please let me know.

Sincerely,

Enclosure

ATTACH.

Steve Oesch -- Office Chief Concel, National Highway Traffic Safety Administration

Dear Mr. Oesch:

The increasing popularity of convertibles in recent years has led to many questions on the effect of Federal auto safety laws on this practice.

Marquis Coachcrafters manufacture convertible conversions on new O.E.M. front wheel drive Cadillac Sedan De Villes. As a manufacturer of new vehicles, my question to you pretains to Standard 208 and 209, Title #49 of the U.S. Code. Standard 208 states that a seat belt must cover 95% of a persons body to meet Federal standards. But in Standard 209, paragraph 54.1.1.2 states that any automobile that is open aired or a convertible has the option of paragraph 4.1.2.3.2. This option states that Type 1 (lap belt) or Type 2 (combo lap and shoulder) conforms to Federal safety laws 208 and 209.

The information I obtained was from a Mr. Tom Grubbs. He may be reached at the following number. (202) 426-2807.

Thank you for your time, consideration and reply.

Your truly,

Adam Humes General Manager -- MARQUIS COACHCRAFTERS