Council Directive of 21 December 1977 on the approximation of the laws of the Member States relating to the wiper and washer systems of motor vehicles (78/318/EEC) (repealed)

ANNEX IV U.K. PROCEDURE FOR DETERMINING VISION AREAS ON WINDSCREENS OF CATEGORY M₁ VEHICLES IN RELATION TO THE V POINTS

1. POSITIONS OF THE V POINTS U.K.

1.1. The positions of the V points in relation to the R point, as indicated by XYZ coordinates from the three-dimensional reference grid, are as shown in Tables I and II. U.K.

1.2. Table I indicates the basic coordinates for a design seat-back angle of 25°. The positive direction for the coordinates is indicated in figure 1 of Annex III. U.K.

TABLE I

V point	X	Y	Z
V1	68 mm	— 5 mm	665 mm
V2	68 mm	— 5 mm	589 mm

1.3. Correction for design seat-back angles other than 25° U.K.

1.3.1. Table II shows the further corrections to be made to the X and Z coordinates of each V point when the design seat-back angle is not 25°. The positive direction for the coordinates is shown in figure 1 of Annex III. U.K.

TABLE II

Seat-back angle(in °)	Horizontal coordinatesΔ X	Vertical coordinatesΔ Z	Seat-back angle(in °)	Horizontal coordinatesΔ X	Vertical coordinatesΔ Z
5	— 186 mm	28 mm	23	— 18 mm	5 mm
6	— 177 mm	27 mm	24	— 9 mm	3 mm
7	— 167 mm	27 mm	25	0 mm	0 mm
8	— 157 mm	27 mm	26	9 mm	— 3 mm
9	— 147 mm	26 mm	27	17 mm	— 5 mm
10	— 137 mm	25 mm	28	26 mm	— 8 mm
11	— 128 mm	24 mm	29	34 mm	— 11 mm
12	— 118 mm	23 mm	30	43 mm	— 14 mm
13	— 109 mm	22 mm	31	51 mm	— 18 mm
14	— 99 mm	21 mm	32	59 mm	— 21 mm
15	— 90 mm	20 mm	33	67 mm	— 24 mm
16	— 81 mm	18 mm	34	76 mm	— 28 mm
17	— 72 mm	17 mm	35	84 mm	— 32 mm
18	— 62 mm	15 mm	36	92 mm	— 35 mm
19	— 53 mm	13 mm	37	100 mm	— 39 mm
20	— 44 mm	11 mm	38	108 mm	— 43 mm
21	— 35 mm	9 mm	39	115 mm	— 48 mm
22	— 26 mm	7 mm	40	123 mm	— 52 mm

2. VISION AREAS U.K.

2.1. Two vision areas shall be determined from the V points. U.K.

2.2. Vision area A is the area on the outer surface of the windscreen bounded by the following four planes extending forward from the V point (see figure 1): U.K.

• a vertical plane passing through V₁ and V₂ and at an angle of 13° to the left of the X axis;

• a plane parallel to the Y axis, passing through V₁ and at an upward angle of 3° from the X axis;

• a plane parallel to the Y axis, passing through V₂ and at a downward angle of 1° from the X axis;

• a vertical plane passing through V₁ and V₂ and at an angle of 20° to the right of the X axis.

2.3. Vision area B is the area of the outer surface of the windscreen which is more than 25 mm from the outer edge of the transparent area and is bounded by the intersection of the following four planes with the outer surface of the windscreen (see figure 2): U.K.

• a plane parallel to the Y axis, passing through V₁ and at an upward angle of 7° from the X axis;

• a plane parallel to the Y axis, passing through V₂ and at a downward angle of 5° from the X axis;

• a vertical plane passing through V₁ and V₂ and at an angle of 17° to the left of the X axis;

• a plane symmetrical to the former plane in relation to the median longitudinal plane of the vehicle.