21. The expert from Poland, in his capacity of Co-Chair of the Informal Working Group on Visibility, Glare and Levelling (IWG VGL), reported on the IWG activities and requested GRE to provide guidance on a number of issues, including but not limited to:
a) Which factors with potential impact on visibility and glare should be addressed by IWG;
b) Whether the work should focus only on Regulation No. 48 (i.e., M and N categories of vehicles) or other categories (L and T) should be considered as well;
c) Whether the requirement for periodic technical inspections (PTI) should be included in the scope;
d) To which extent the available studies and previous GRE documents should be taken into account;
e) Whether IWG or GRE should vote on issues for which no consensus had been found.
22. Various experts stressed the complexity of these issues and called for a pragmatic approach that would rely on the available studies and proposals. The experts from Germany and Japan were of the view that automatic levelling should be taken out of the scope of IWG VGL and addressed by GRE directly. The experts from France and Italy felt that both manual and automatic levelling should be considered by IWG VGL.
23. Based on the above discussion, GRE requested IWG VGL to review its Terms of Reference and prepare modifications for adoption by GRE, as may be necessary. GRE also agreed that, for the time being, IWG VGL should focus on Regulation No. 48 and vehicle categories M and N only, leaving aside the PTI requirements. Finally, GRE stressed the need to follow a consensus approach rather than to vote on controversial points. GRE noted that the expert from Germany would no longer be in a position to co-Chair IWG VGL and encouraged other experts to volunteer for this post.