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Interpretation ID: nht88-3.68

TYPE: INTERPRETATION-NHTSA

DATE: 10/14/88

FROM: ERIKA Z. JONES -- CHIEF COUNSEL NHTSA

TO: WILLIAM E. LAWLER -- SPECIFICATIONS MANAGER INDIANA MILLS & MANUFACTURING, INC.

TITLE: NONE

ATTACHMT: LETTER DATED 09/17/87 TO ERIKA Z. JONES FROM WILLIAM E. LAWLER, OCC - 1043

TEXT: Dear Mr. Lawler:

This responds to your letter seeking an interpretation of Standard Nos. 208, Occupant Crash Protection (49 CFR @ 571.208) and 209, Seat Belt Assemblies (49 CFR @ 571.209). I regret the delay in this response.

Specifically, you asked about a safety belt installation at the driver's seat of a vehicle with a gross vehicle weight rating in excess of 10,000 pounds. A customer of yours designed a lap/shoulder belt system with a continuous webbing feature and with a floor-mounted automatic locking retractor (ALR) for the belt system. Your company was concerned that this proposed design would not comply with the requirements of S4.3(i) and S5.2(i) of Standard No. 209, which limit the extent to which ALR's can move between locking positions and the retraction force that can be exerted by ALR's. Additionally, your letter stated that sections S4.1.2.3, S4.2.2, and S7.1 of Standard No. 208, "though dealing with lighter vehicles, seem to imply the intent of minimal u pper torso restriction."

To address these concerns, you made two modifications to the customer's proposed design. The first modification was to sew the latchplate to the webbing to convert the continuous webbing into a separate lap belt and upper torso restraint. The second mo dification was to place a manual adjusting device on the upper torso restraint. You asked for an opinion on these modifications.

The requirements for safety belts on vehicles manufactured before September 1, 1990, with a gross vehicle weight rating in excess of 10,000 pounds are set forth in section S4.3.1 of Standard No. 208 for trucks and multipurpose passenger vehicles and in s ection S4.4.1 for buses. Both of these sections require that the driver's seating position in heavy vehicles be equipped with a complete automatic protection system or with a Type 1 or Type 2 seat belt assembly that conforms to Standard No. 209. The re quirements for safety belts on heavy vehicles manufactured on or after September 1, 1990 are set forth in section S4.3.2 of Standard No. 208

for trucks and multipurpose passenger vehicles and in section S4.4.1 for buses. These heavy vehicles must either have a complete automatic protection system at the driver's seating position or be equipped with a Type 1 or Type 2 seat belt assembly t hat conforms to Standard No. 209, S7.2 of Standard No. 208, and include either an emergency locking retractor or an automatic locking retractor that satisfies some additional performance requirements.

Your customer has chosen to comply with Standard No. 208 by installing a belt system at the driver's seating position. Therefore, the vehicles in question would comply with the applicable requirements of Standard No. 208 if the belt assembly complies wi th the requirements of S4.3.1 or S4.4.1, if the vehicles are manufactured before September 1, 1990, or with the requirements of S4.3.2 or S4.4.2, if the vehicles are manufactured on or after September 1, 1990. Your letter does not provide sufficient inf ormation for us to offer any opinion on whether your customer's design or your design would comply with S4.3(i) and S5.2(i) of Standard No. 209. If both comply with all applicable requirements of Standard No. 209, either may be installed at the driver's seating position in vehicles manufactured before September 1, 1990. If both comply with all applicable requirements of Standard No. 209 and the additional requirements set forth in S4.3.2 and S4.4.2 of Standard No. 208, either may be installed at the d river's seating position in vehicles manufactured on or after September 1, 1990.

You also referred to an implied agency intent of minimal upper torso restriction by the belt assemblies in heavy vehicles. When the agency promulgates a safety standard specifying performance requirements for vehicles or items of equipment to accomplish a particular safety purpose, that safety standard sets forth all requirements with which the vehicles or equipment must comply regarding that purpose. If those requirements do not fully address or ensure the implementation of some aspect of that purpos e, then to that extent, that aspect is not part of the standard, even if NHTSA intended it to be part of the standard. Any aspect of performance that is not set forth in the requirements of the standard is, therefore, not relevant to determining whether the vehicles or equipment comply with the performance requirements that are set forth in the standard.

We certainly appreciate your efforts to design a comfortable lap/shoulder belt system for these vehicles, because more comfortable belt systems should increase belt use. Increased use, in turn, helps prevent deaths and/or serious injuries.

Sincerely,