63. The expert from OICA presented ECE/TRANS/WP.29/GRRF/2016/21 proposing to extend the possibility of actuating the service braking system to vehicles of categories M₂ and N₂ below five tons. The proposal received some comments on possible safety risks. The expert from Switzerland explained that his country, due to specific geographic characteristics, had long roads with significant slopes and that the requirements shall take this specificity into consideration. The expert from OICA stated that, due to speed limiter (90 km/h), fully loaded vehicles of category M₂ of N₂ below five tons would have a smaller kinetic energy than fully loaded vehicles of category N₁ driving at 130 km/h, therefore, the proposal is not introducing any road safety issue. The expert from Denmark noted that a tell-tale could be provided, in combination with the system actuating the service brakes, to make the driver aware of the service brake application. GRRF agreed to continue consideration of this agenda item at September 2016 session of GRRF and invited GRRF to provide evidences that no additional safety risk would be expected if the requested extension would be granted.

67. The expert from OICA introduced ECE/TRANS/WP.29/GRRF/2015/44 proposing to extend the possibility of actuating the service braking system as described in Regulation No. 89 to vehicles of categories M2 and N2 below 5t. Some experts expressed concerns related to the risk of “hot brakes” phenomena when the (adjustable) speed limitation device would function down hills. The expert from OICA agreed to provide more information about the proposal to be presented at the February 2016 session of GRRF. GRRF agreed to resume consideration on this item at its February 2016 session and requested the secretariat to dedicate an agenda item to Regulation No. 89.