9. Taking into account the recent GTB study (GRE-71-32), the expert from France proposed to delete a design restrictive requirement for an automatic levelling device for all headlamps with LED light sources, irrespective of their luminous flux (ECE/TRANS/WP.29/GRE/2014/34). GRE agreed that this proposal should be tackled at the next session, in conjunction with the GTB proposals on visibility and glare issues (see para. 14 below).

14. The expert from GTB recalled the outcome of the GTB study on visibility and glare (GRE-71-32) and presented a first draft of amendments to Regulation No. 48 addressing the visibility distance and glare issues (GRE-72-07). This proposal received comments by the expert from Poland (GRE-72-23-Rev.1). Various experts generally agreed that the current requirement for automatic levelling in Regulation No. 48 (2,000 lm luminous flux of the light source) should be replaced by other deciding factors for headlamp glare, such as the vehicle pitch angle, loading conditions and initial headlamp aiming. However, no consensus was reached on exact replacement criteria. The expert from UK suggested that an informal group be established to speed up the finalization of the amendment proposal. The experts from France, Germany, Italy and the Netherlands were of the view that GTB should be tasked to submit a concrete proposal to the next session of GRE. GRE invited GTB, OICA and interested Contracting Parties to organize a meeting with the aim to elaborate a revised proposal. The experts from France, Germany, Italy, Netherlands, Poland and UK expressed their interest in participating in this meeting.

11. The expert from GTB introduced the results of their studies on visibility and glare (GRE-71-15 and GRE-71-32). The study concentrated on levelling in relation to load and its major objectives were to improve the understanding of different factors that influence visibility and glare and to identify results of the study that might reveal alternatives for automatic static levelling. The expert from OICA recalled their presentations on loading definitions and achievable aiming tolerances (see also GRE-67-27 and GRE-68-20).

12. The expert from Poland introduced a revised proposal ECE/TRANS/WP.29/GRE/2014/11 on initial aiming of dipped-beam headlamps and considering the original 75 +/-25 m visibility distance requirement.

13. GRE was of the view that the study had pointed out that the type of light source and its luminous flux are not the deciding factors in headlamp glare. Instead, the most important factors seem to be the vehicle pitch angle, loading conditions and initial headlamp aim. Therefore, the light source choice (LED) and the light source 2,000 lm criteria in UN Regulation No. 48 were found unnecessarily restrictive and creating barriers to new technologies. Different views were expressed whether automatic levelling should become a requirement for all categories of vehicles and light sources. Operating voltage was also mentioned as an additional factor of glare.

14. GRE invited the experts from Poland, GTB and OICA to submit one coherent proposal for amendments to UN Regulation No. 48 addressing the visibility distance and glare issuto the next GRE session.