Interpretation ID: 1983-2.23

TYPE: INTERPRETATION-NHTSA

DATE: 07/01/83

FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA

TO: MMC Services Inc.

TITLE: FMVSS INTERPRETATION

TEXT:

Mr. Masakatsu Kano Executive Vice President MMC Services Inc. 3000 Town Center, Suite 1960 Southfield, Michigan 48075

Dear Mr. Kano:

This responds to your letter of April 20, 1983, asking several questions concerning the requirements for armrests in Safety Standard No. 201, Occupant Protection in Interior Impact. That standard requires, as one optional means of compliance (S3.5.1(c)), that each armrest have at least 2 inches of coverage withing the pelvic impact area, when measured vertically in side elevation. You ask whether this 2-inch measurement may be made from the outermost points of the base of the armrest as it fits against the door inner trim, or whether the measurement must be made from the inboard portion of the armrest that would actually contact a vehicle occupant. You also ask if the standard permits an armrest surface that would contact an occupant to be tilted at a 15 degree angle from the vertical, and whether it permits that surface to have "low moles" or "shallow bezels" (i.e., minor protrusions or indentations).

With reference to the drawing included in your letter, Standard No. 201 would require the specified 2-inch measurement to be taken at the "H1" parameters, rather than the "HO". The purpose of the requirement is to ensure that there is at least 2 inches of coverage within the pelvic impact area. For this requirement to be meaningful, the covered surface must be contactable by the vehicle occupant. The vehicle occupant would not contact the base of the armrest illustrated in your drawing, regardless of its vertical length.

Paragraph S3.5.1(c) does not preclude "moles" or "bezels" in the armrest, since there are no limitations on radius of curvature. A "mole" which projected only moderately into the vehicle interior would be included in the calculation to determine compliance with the requirement for 2 inches of covered surface. If a mole projected so far into the vehicle interior that it would prevent pelvic contact with the rest of the armrest, however, only the mole would be included in the calculation.

By the same token, while a "bezel" is not precluded, it is not included in the calculation if it is so deep that it cannot be contacted.

Paragraph S3.5.1(c) does not specify any particular angle at which an armrest must be set with relation to the door inner trim. Therefore, it is permissible for the inboard surface of the armrest illustrated in your drawing to make an angle of 15 degrees from the vertical.

Finally, I would point out that paragraph S3.5.1(c) is one of three optional means of compliance for manufacturers who install armrests. A manufacturer may also satisfy the requirements of Standard No. 201 by complying with either S3.5.1(a) or S3.5.1(b), in which case it is not necessary to provide 2 inches of coverage within the pelvic impact area.

Sincerely,

Original Signed By Frank Berndt Chief Counsel

Mr. Frank Berndt Chief Counsel National Highway Traffic Safety Administration U.S. Department of Transportation 400 Seventh Street, S.W. Washington D.C. 20590

Subject: Interpretation of FMVSS 201: Occupant Protection In Interior Impact

Dear Mr. Berndt:

This is to ask your interpretation of FMVSS 201; S 3.5.1 (C) (armrests) which states, "Along not less than 2 continuous inches of its length, the armrest shall, when measured vertically in side elevation, provide at least 2 inches of coverage within the pelvic impact area" is not clear about the measuring method, therefore, the following is our own interpretation. (Reference to the figure of attachment);

We interpret the "at least 2 inches" length "HO" which is measured vertically in side elevation.

If your interpretation is not "HO" but "H1",

i) Is it acceptable that the lean of the armrest side- surface is 15 degrees (0=15) or less?

ii) Is it allowable that the armrest side-surface has the low mole or the shallow bezel, with the following dimensions:

-- Width of mole or bezel "W1" or "W2" is equal to or less than 0.5 inch.

-- Height of mole "D2" and depth of bezel "D1" are equal to or less than 0.2 inch, respectively.

Very truly yours,

Masakatsu Kano Executive Vice President