50. The experts from GTB presented status reports of the GTB Working Group activities (GRE-72-27, GRE-72-28, GRE-72-29, GRE-72-30). Concerning the GTB activities to improve the situation with non-approved LED retrofit light sources used as replacement parts for filament light source, the experts from France and Italy were of the view that such replacement should be prohibited on safety concerns.

12. The expert from GTB presented proposals for amendments to Regulation No. 128 and to the Consolidated Resolution (R.E.5) which introduce requirements and test specifications for light emitting diode (LED) substitute light sources as well as several new LED substitute light source categories (ECE/TRANS/WP.29/GRE/2017/2, ECE/TRANS/WP.29/GRE/2017/3, GRE-77-02, GRE-77-03, GRE-77-15, GRE-77-22). These proposals were accompanied by collective amendments to Regulations Nos. 48, 53, 74, 86 with the requirements for LED substitute light sources (ECE/TRANS/WP.29/GRE/2017/4). The expert from GTB explained that the proposed approach was based on the following principles:

• Lamps may be approved with a filament light source and its corresponding LED substitute light source, when fitting in the same holder, and providing an equivalent photometric performance;
• Lamps equipped with LED substitute light sources should be tested with both the filament lamp and the LED substitute light source.

14. The expert of Germany commented on the GTB proposals (GRE-77-29). GRE generally advocated the idea of allowing for LED substitute lights sources, given their high energy efficiency. At the same time, the experts from France, Germany, Netherlands, Spain and UK pointed out the risks associated with the improper use of aftermarket LED products in lamps, which were not approved for such light sources, and called for developing a set of preventive measures, including raising public awareness and giving warnings to consumers. Several technical issues were also questioned, in particular, the proposed G-marking for LEDs with a correlated colour temperature below 3,000 K. GRE invited GTB to address the comments received and agreed to continue the consideration of this issue at the next session on the basis of revised documents to be prepared by GTB.