Working draft prepared by Germany for the SLR informal group.

Initial proposal for discussion to introduce provisions to address risk of delayed response to a signal due to sun load impact on conspicuity.

Proposal to allow under specified conditions the use of logos inside the illuminating surface of a signalling lamp.

Proposal to introduce requirements for testing the sun load impact to avoid delays in the perception of light signals under certain sunlight conditions.

Proposal to introduce requirements for testing the sun load impact, which can delay the perception of a signal in such a way that it may became a serious safety issue, if the sun load impact goes above a defined ratio.

Proposal to allow the use of logos inside the illuminating surface of a signalling lamp under certain conditions.

Proposal to allow the use of manufacturer logos in the internal structure of optical components and/or in the outer lens within the apparent surface of a signalling lamp.

Proposal to allow the use of manufacturer logos inside the illuminant surface of a signalling lamp.

Proposal to allow the use of manufacturer logos inside the illuminant surface of a signalling lamp.

Proposal to enable the approval under UN R74 of a front and rear indicator that can be activated simultaneously, to allow the installation of optional direction indicators at national level on bicycles (including vehicles with a maximum design speed not exceeding 25 km/h), and to introduce a new symbol “-“ under UN R148 between the symbols indicating the functions of the device in order to differentiate a device which fulfils the requirement of a front indicator of category 11 and a rear indicator of category 12 that cannot be activated simultaneously from one that can.

Idea from Germany to simplify the lifetime requirements for non-replaceable light source(s) and non-replaceable light source module(s) given that the lifetime of a LED light source is much higher than the lifetime of a filament lamp.

Proposal to improve the visibility of direction indicators. The proposal modifies UN R48 and UN R148 requirements for direction indicator lamps grouped with stop lamps. Key changes include: requiring 75% of the rear direction indicator’s apparent surface to be more than 25mm from the stop lamp; positioning direction indicators at specified distances from the vehicle’s outer edge; and establishing a minimum apparent surface area of 30cm² for rear direction indicators. The justification cites existing installations showing inadequate visibility and references luminance studies supporting the 30cm² minimum area requirement.

A literature review on direction indicator visibility presents research on vehicle lighting design, visibility, and signalling. Sources include studies on overlapping and interlocking of lights, and dynamic evaluation of automobile rear lighting configurations.