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Interpretation ID: 21419.drn





    Mr. Mac Yousry
    Global Vehicle Services, Corp.
    1238 West Grove Avenue
    Orange, CA 92865


    Dear Mr. Yousry:


    This responds to your request for an interpretation of wiped or cleared areas specified in Standard No. 104, Windshield Wiping and Washing Systems. You asked two questions, which are answered below.

    Your letter concerns S4.1.2 of Standard No. 104, which establishes three windshield areas, designated as "A," "B," and "C," for passenger cars. Each area is required to have a certain percentage of the windshield area wiped as indicated in Figures 1 and 2 of SAE Recommended Practice J903a (May 1966), using the angles specified in Tables I, II, III and IV of Standard No. 104. The standard also provides that the percentage of each area required to be cleared must also be within the area bounded by a perimeter line on the glazing surface one inch from the edge of the daylight opening.

    You note that Standard No. 104 does not specify whether Areas A, B and C must fall inside the boundaries of the daylight opening of the windshield. You state that new passenger car designs may utilize smaller windshields, even though the overall width of the vehicle may not be any narrower than typical passenger cars. You believe that on such smaller windshields, parts of Areas A, B, and C may fall outside the daylight opening or even outside the area bounded by the windshield frame.

    Your first question asks "Must all of the area of windshield areas A, B and C fall inside the area of the windshield bounded by a perimeter line on the glazing surface one inch from the edge of the daylight opening?"

    The answer is no. In an interpretation letter of May 6, 1997, to Mr. Jiri Misik (copy enclosed), the National Highway Traffic Safety Administration stated that Area A is that portion of the total area bounded by the angles in Tables I through IV of Standard No. 104 that is also within a perimeter 25 mm within the daylight opening of the windshield frame. The agency noted that it is not necessary that the windshield be large enough to contain the whole area bounded by angles (of which 16 to 18 is the left border).

    Although the answer to Mr. Misik addressed only Area A, the analysis also applies to Areas B and C.

    Your second question asks:

      (a)  Should the percentage of the areas A, B and C, which must be wiped, be calculated utilizing the full areas of A, B, and C even if parts thereof are outside the daylight opening of the windshield?

      (b)  Or, should the percentages of areas A, B and C, which must be wiped, be calculated utilizing only parts of areas A, B and C that actually fall inside the area of the windshield bounded by a perimeter line on the glazing surface one inch from the edge of the daylight opening?

    As explained below, the answer to the second question is (b). In Standard No. 104, S4.1.2 states the following:

    Wiped area. When tested wet in accordance with SAE Recommended Practice J903a, May 1966, each passenger car windshield wiping system shall wipe the percentage of Areas A, B, and C of the windshield (established in accordance with S4.1.2.1) that (1) is specified in column 2 of the applicable table following subparagraph S4.1.2.1 and (2) is within the area bounded by a perimeter line on the glazing surface 25 millimeters from the edge of the daylight opening.

    The description and control of the minimum windshield area to be wiped is described at S3.1 of SAE Standard J903a (copy enclosed). S3.1.2.1 states in part:

    The minimum windshield area that shall be wiped is described by the use of three specific areas on the windshield glazing surface. The three areas are identified in Table 1 as areas A, B, and C. Each area has been established using the angles of Table 1 applied as shown in Figs. 1 and 2. In Fig. 1 (side view), the upper and lower boundary of the area is established by the intersection of two planes, tangent to the upper and lower sides of the eye range contour, with the windshield glazing surface. The planes are fixed by angles above and below the glazing surface reference line. In Fig. 2 (plan view), the left and right boundaries of the area are established by the intersection of two planes tangent to the left and right sides of the eye range contour. The planes are fixed by angles to the left and right of the plan view reference line. ...

    S3.1.2.1's description means that Areas A, B and C are not fixed, predetermined areas for all windshields, but are areas that vary from windshield to windshield. The variables are the angle of measurement and the width of the car. S4.1.2 of Standard No. 104 adds another variable by describing Areas A, B and C as within the area bounded by a perimeter line on the glazing surface 25 millimeters from the edge of the daylight opening.

    Please note that in Standard No. 104, Tables I, II, III, and IV all specify that after the test is conducted, a minimum of 80% of Area A must be wiped, a minimum of 94% of Area B must be wiped, and a minimum of 99% of Area C must be wiped.

    I hope this information is helpful. If you have any further questions, please feel free to contact Dorothy Nakama of my staff at this address or by telephone at (202) 366-2992.


    Sincerely,


    Frank Seales, Jr.
    Chief Counsel

    Enclosures

    ref:104
    d.8/11/00