Document ID: chunk:federal_register_of_legislation:F2023C00228:reg:1:p24
Version: federal_register_of_legislation:F2023C00228
Segment Type: reg
Provision Reference: reg 1 (pt 24/40)
Character Range: 400914–404028

of HSB units designed to meet the requirements of left-hand traffic, the "cut-off" on the right half of the screen is horizontal;

       8.2.2.2. this horizontal part of the "cut-off" is situated on the screen 25 cm below the level hh (see annex 4 to this Regulation);

       8.2.2.3. The "elbow" of the "cut-off" is on line vv. [8/]

       8.2.3. When so adjusted, the HSB unit need meet only the requirements laid down in paragraphs 8.2.5. and 8.2.6. below if approval thereof is sought solely for provision of a passing beam; [9/] if it is intended to provide both a passing beam and a driving beam it shall meet the requirements laid down in paragraphs 8.2.5., 8.2.6. and 8.3.

       8.2.4. Where an HSB unit so adjusted does not meet the requirements laid down in paragraphs 8.2.5., 8.2.6. and 8.3., its alignment may be changed provided that the axis of the beam is not displaced laterally by more than 1 degrees (= 44 cm) to the right or left. [10/] To facilitate alignment by means of the "cut-off", the unit may be partially occulted in order to sharpen the "cut-off".

       8.2.5. The illumination produced on the screen by the passing beam shall meet the following requirements:

POINT ON MEASURING SCREEN         REQUIRED ILLUMINATION IN LUX
HSB UNITS FOR RIGHT-HAND TRAFFIC  HSB UNITS FOR LEFT-HAND TRAFFIC
                                                                   <0.4
B 50 L                            B 50 R                           >12
75 L                              75 L                             <12
75 L                              75 R                             >12
50 L                              50 R                             <15
50 R                              50 L                             >6
50 V                              50 V                             >2
25 L                              25 R                             >2
25 R                              25 L                             <0.7
                                                                   >3
At any point in zone III
"   "   "   "   IV                <2 x (E50R or * E50L)
"   "   "   "   I

       * E50R and E50L are the illuminations actually measured.

       8.2.6. There shall be no lateral variations detrimental to good visibility in any of the Zones I, II, III and IV.

       8.3. Requirements concerning the driving beam

       8.3.1. In the case of an HSB unit designed to provide a driving beam and a passing beam, measurements of the illumination produced on the screen by the driving beam shall be taken with the same HSB unit alignment as for measurements under paragraphs 8.2.5. and 8.2.6.; if the HSB unit provides a driving beam only, it shall be so adjusted that the area of maximum illumination is centred on the point of intersection HV of lines hh and vv; such an HSB unit need meet only the requirements laid down in paragraph 8.3.

       8.3.2. The illumination produced on the screen by the driving beam shall meet the following requirements:

       8.3.2.1. The point of intersection HV of lines hh and vv shall be situated within the isolux