Document ID: chunk:federal_register_of_legislation:F2023C00919:body:0:p32
Version: federal_register_of_legislation:F2023C00919
Segment Type: other
Provision Reference: 
Character Range: 100795–103712

or
(c) When the lamps is being used to provide another lighting function;
provided that any variation in the photometric characteristics is in compliance with the technical provisions for the lamp concerned.
5.9.3.                              The photometric characteristics of a direction indicator lamp of categories 1, 1a, 1b, 2a or 2b may be varied during a flash by sequential activation of light sources as specified in paragraph 5.6. of Regulation No. 6.
This provision shall not apply when direction indicator lamps of categories 2a and 2b are operated as emergency stop signal according to paragraph 6.23.1. of this Regulation.
5.10.                                No red light which could give rise to confusion shall be emitted from a lamp as defined in paragraph 2.7. in a forward direction and no white light which could give rise to confusion, shall be emitted from a lamp as defined in paragraph 2.7. in a rearward direction. No account shall be taken of lighting devices fitted for the interior lighting of the vehicle. In case of doubt, this requirement shall be verified as follows:
5.10.1.                          For the visibility of red light towards the front of a vehicle, with the exception of a red rearmost side-marker lamp, there shall be no direct visibility of the apparent surface of a red lamp if viewed by an observer moving within Zone 1 as specified in Annex 4;
5.10.2.                          For the visibility of white light towards the rear, with the exception of reversing lamps and white side conspicuity markings fitted to the vehicle, there shall be no direct visibility of the apparent surface of a white lamp if viewed by an observer moving within Zone 2 in a transverse plane situated 25 m behind the vehicle (see Annex 4);
5.10.3.                          In their respective planes, the zones 1 and 2 explored by the eye of the observer are bounded:
5.10.3.1.                    In height, by two horizontal planes 1 m and 2.2 m respectively above the ground;
5.10.3.2.                    In width, by two vertical planes which, forming to the front and to the rear respectively an angle of 15° outwards from the vehicle's median longitudinal plane, pass through the point or points of contact of vertical planes parallel to the vehicle's median longitudinal plane delimiting the vehicle's overall width; if there are several points of contact, the foremost shall correspond to the forward plane and the rearmost to the rearward plane.
5.11.                                The electrical connections shall be such that the front and rear position lamps, the end-outline marker lamps, if they exist, the side-marker lamps, if they exist, and the rear registration plate lamp can only be switched ON and OFF simultaneously.
5.11.1.                          This condition does not apply:
5.11.1.1.                    When front and rear position lamps are switched ON,