Interpretation ID: 2744y
Manager, Regulations and Compliance
Volvo Cars of North America
Rockleigh, NJ 07647
Dear Mr. Shapiro:
This responds to your request for an interpretation of Standard No. 210, Seat Belt Assembly Anchorages (49 CFR 571.210). More specifically, you asked about the anchorage location requirements for the upper torso portion of Type 2 safety belts (i.e., lap/shoulder belts), set forth in S4.3.2 of Standard No. 210. I am pleased to have this opportunity to explain those regulatory requirements for you.
Before discussing the substantive issues raised in your letter, I would like to respond to your request that NHTSA not publicly release the design drawings for this proposed new safety belt design. We hereby grant your request. We will make available to the public your incoming letter and this response, but not the design drawings.
Your letter stated that Volvo is designing lap/shoulder belts for the rear seating positions of proposed future vehicles. The retractor for the upper end of the shoulder belt portion of these safety belts would be located in the seat back, and not within the acceptable anchorage location zone shown in Figure 1 of Standard No. 210. However, the shoulder belt webbing would pass through a device on the top of the seat back that you called a "belt anchor" on the way to the retractor. This "belt anchor" would bear most of the loads imposed on the shoulder belts from the forward direction, and would redirect the shoulder belt webbing downward to the retractor. This function is similar to that performed by D-rings for many current designs of manual lap/shoulder safety belts. The "belt anchor" would be within the acceptable anchorage location zone shown in Figure 1 of Standard No. 210. You asked if this design would comply with the requirements of S4.3.2 of Standard No. 210. The answer to your question is yes.
Both the "belt anchor" and the retractor would be "anchorages" within the meaning of S3 of Standard No. 210 for the shoulder belt, because both would transfer belt loads to the vehicle structure. However, S4.3.2 does not require that both these anchorages comply with the anchorage location requirements. Instead, S4.3.2 provides that, "the seat belt anchorage for the upper end of the upper torso restraint shall be located within the acceptable range shown in Figure 1." NHTSA has interpreted this language as follows. If there is a single "anchorage" for the upper end of the shoulder belt, that single "anchorage" must comply with the anchorage location requirements. If there is more than one "anchorage" for the upper end of the shoulder belt, the uppermost of these multiple anchorages must comply with the anchorage location requirements.
I hope this information is helpful. Please let me know if you have any further questions or need some additional information on this subject.
Sincerely,
Paul Jackson Rice Chief Counsel
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