Search Interpretations


Mr. Lance Tunick

Vehicle Services Consulting, Inc.

P.O. Box 23078

Santa Fe, NM 87502-3078

Dear Mr. Tunick:

This responds to your letter asking several questions about Federal Motor Vehicle Safety Standards (FMVSS) No. 207, Seating Systems, No. 208, Occupant Crash Protection, and No. 210, Seat Belt Assembly Anchorages. Your questions are addressed below.

Issues Related to FMVSS No. 210 and FMVSS No. 207




Your first questions relate to S4.2.2 of FMVSS No. 210. That paragraph reads as follows:

S4.2.2  Except as provided in S4.2.5, and except for side facing seats, the anchorages, attachment hardware, and attachment bolts for any of the following seat belt assemblies shall withstand a 3,000 pound force applied to the lap belt portion of the seat belt assembly simultaneously with a 3,000 pound force applied to the shoulder belt portion of the seat belt assembly, when tested in accordance with S5.2 of this standard:

(a) Type 2 and automatic seat belt assemblies that are installed to comply with Standard No. 208 (49 CFR 571.208); and

(b) Type 2 and automatic seat belt assemblies that are installed at a seating position required to have a Type 1 or Type 2 seat belt assembly by Standard No. 208 (49 CFR 571.208).

S4.2.5, referenced at the beginning of S4.2.2, provides:

S4.2.5 The attachment hardware of a seat belt assembly, which is subject to the requirements of S5.1 of Standard No. 208 (49 CFR 571.208) by virtue of any provision of Standard No. 208 other than S4.1.2.1(c)(2) of that standard, does not have to meet the requirements of S4.2.1 and S4.2.2 of this standard.

Your Question 1


Your first question asks: When is S4.2.2 of FMVSS No. 210 not applicable by virtue of S4.2.5? You stated that a passenger car manufactured after September 1, 2006 must have a Type 2 seat belt assembly at each front outboard designated seating position by virtue of S4.1.5 of 49 CFR 571.208 and not by virtue of S4.1.2.1(c)(2). You asked whether it is correct that passenger cars manufactured after September 1, 2006 do not have to meet the strength requirements of S4.2.1 and S4.2.2 of FMVSS No. 210.

In considering your question, we have reviewed the history of the provision at issue. On December 5, 1991, in a final rule relating to responses to petitions for reconsideration published in the Federal Register (56 FR 63676, 63677),[1] NHTSA decided to exclude from FMVSS No. 210 the attachment hardware of dynamically tested manual safety belt systems which are the only occupant restraint at a seating position. The agency believed that the FMVSS No. 210 tests were unnecessarily redundant for these dynamically tested systems.

However, NHTSA also explained that it does not consider a manual belt installed at a seating position that is also equipped with an air bag to be dynamically tested, and therefore, the attachment hardware of these belts was subjected to the FMVSS No. 210 strength tests. To accomplish this, the agency included the provision in FMVSS No. 210 citing S4.1.2.1(c)(2) of FMVSS No. 208.

Subsequent to this, the agency has not amended or proposed to amend this requirement of FMVSS No. 210. However, the agency did amend FMVSS No. 208 in a way that made the cross-reference in FMVSS No. 210 outdated, while not making conforming changes to FMVSS No. 210.

Your Question 2

Your second question asks: In a case where S4.2.2 of FMVSS No. 210 is applicable, what is the force imposed on the seat under S4.2(c) of FMVSS No. 207?

S4.2 of FMVSS No. 207 reads in relevant part as follows:

S4.2   General performance requirements. When tested in accordance with S5., each occupant seat, other than a side-facing seat or a passenger seat on a bus, shall withstand the following forces, in newtons. . . .

(c) For a seat belt assembly attached to the seatthe force specified in paragraph (a), if it is a forward facing seat, or paragraph (b), if it is a rearward facing seat, in each case applied simultaneously with the forces imposed on the seat by the seat belt assembly when it is loaded in accordance with S4.2 of 571.210 . . .

In your letter, you state your belief that it is necessary to identify the force imposed on the seat by the seat belt to conduct testing under S4.2(c), and suggest ways of doing so. However, we disagree that it is necessary to identify or calculate these forces. Instead, the seat is loaded as specified in FMVSS No. 210 and the forces specified by FMVSS No. 207 applied simultaneously. Therefore, we do not agree with your suggested interpretation.

You also asked about a reference in Laboratory Test Procedure TP-207-9 which states that the force imposed on the seat frame is 4,950 pounds independent of the seat configuration. This Laboratory Test Procedure refers to the 4,950 pound (force) load when testing a lap belt with the seat system (20 times the weight of the seat).  We note that one of the loading conditions specified in FMVSS No. 210, which applies to lap belts, is a 5,000 pound force. See S4.2.1. The reference you ask about relates to that FMVSS No. 210 loading condition. For this particular compliance testing, we apply a load that is less severe than the 5,000 pounds specified in the standard.


We note, however, that manufacturers are required to certify their vehicles to the FMVSSs and not to the laboratory test procedures. TP-207-9 includes the following note on page 1:

The OVSC Laboratory Test Procedures, prepared for use by independent laboratories under contract to conduct compliance tests for the OVSC, are not intended to limit the requirements of the applicable FMVSS(s). In some cases, the OVSC Laboratory Test Procedures do not include all of the various FMVSS minimum performance requirements. Sometimes, recognizing applicable test tolerances, the Test Procedures specify test conditions which are less severe than the minimum requirements of the standards themselves. Therefore, compliance of a vehicle or item of motor vehicle equipment is not necessarily guaranteed if the manufacturer limits certification tests to those described in the OVSC Laboratory Test Procedures.

Issues related to S4.1.5 and S7.1.1 of FMVSS No. 208



You asked several questions related to S4.1.5 and S7.1 of FMVSS No. 208. These paragraphs read as follows:

S4.1.5   Passenger cars manufactured on or after September 1, 1996.

S4.1.5.1   Frontal/angular automatic protection system. (a) Each passenger car manufactured on or after September 1, 1996 shall:

. . .

(3) At each front designated seating position that is an outboard designated seating position, as that term is defined at 49 CFR 571.3, and at each forward-facing rear designated seating position that is a rear outboard designated seating positions, as that term is defined at S4.1.4.2(c) of this standard, have a Type 2 seat belt assembly that conforms to Standard No. 209 and S7.1 through S7.3 of this standard, and, in the case of the Type 2 seat belt assemblies installed at the front outboard designated seating positions, meet the frontal crash protection requirements with the appropriate anthropomorphic test dummy restrained by the Type 2 seat belt assembly in addition to the means that requires no action by the vehicle occupant. . . .

S7.1   Adjustment.

S7.1.1  Except as specified in S7.1.1.1 and S7.1.1.2, the lap belt of any seat belt assembly furnished in accordance with S4.1.2 shall adjust by means of any emergency-locking or automatic-locking retractor that conforms to 571.209 to fit persons whose dimensions range from those of a 50th percentile 6-year-old child to those of a 95th percentile adult male

. . .

Your Questions


You note in your letter that S7.1.1 specifies certain requirements for seat belt assemblies furnished in accordance with S4.1.2. You ask whether S7.1.1 applies to vehicles manufactured after September 1, 2006, in which the seat belt assemblies are furnished in accordance with S4.1.5.

The answer is yes. The reason for this is that S4.1.5 itself specifies that these vehicles must have seat belt assemblies that conform to S7.1. See S4.1.5.1(2) and (3). We note that the version of S4.1.5 establishing requirements for vehicles manufactured on or after September 1, 1996 was established by NHTSA in the September 1993 final rule implementing the Congressional requirement for light vehicles to be equipped with an air bag and a manual lap/shoulder belt at both the drivers and right front passengers seating position. In the regulatory text specifying requirements for these vehicles, the agency included the adjustment requirements of S7.1.

You also ask whether parts of S7.1 are outdated. The discussion provided above may provide the information you desire in this area. If not, we would need a more specific question from you.

I hope this information is helpful. If you have further questions, please contact Edward Glancy of my staff at (202) 366-2992.


Anthony M. Cooke

Chief Counsel

ref: 207#208#210#101#VSA102(4)


[1] See also Final rule; delay of effective date and response to petitions for reconsideration; 57 FR 32902; July 24, 1992.