44. The expert from Spain introduced the status report of the TF on Engine Fire Suppression Systems for vehicles concerning the International Carriage of Dangerous Goods by Road (ADR). She explained that TF had decided that a new UN Regulation on this subject would be developed and a proposal presented at the April 2025 session of GRSG. The expert from OICA suggested that section 9 of UN Regulation No. 105 would be more suited for these requirements than a new UN Regulation. The expert from Spain stated that TF would take into consideration the suggestion from OICA. She clarified that tyres would not be covered by the proposal of the TF and offered to check the compatibility of the fire to tyre propagation requirements of chapter 9. The secretariat recommended the participation of experts from the Working Party on the Transport of Dangerous (WP.15) in the task force. Finally, GRSG agreed to resume discussion on this subject at its April 2025 session.

45. The expert from OICA introduced GRSG-128-24-Rev.1 superseding ECE/TRANS/WP.29/GRSG/2024/37, on aligning the text of UN Regulation No. 105 with the latest version of ADR. The expert from the Kingdom of the Netherlands argued that the proposed provisions for vehicles with liquid hydrogen subjected to the technical requirements of the UN Global Technical Regulation (UN GTR) No.13 (Hydrogen and Fuel Cells Vehicles), Amendment 1 would create administrative hurdles. He clarified that certifications granted under this UN GTR would be incompatible with type approvals granted according to UN Regulations under the 1958 Agreement. On the suggestion of the secretariat, provisions on liquid hydrogen, stemming from UN GTR No. 13, were added to the proposal and reference to the UN GTR removed (GRSG-128-24-Rev.3). Finally, GRSG adopted GRSG-128-24-Rev.3 and requested the secretariat to submit it as a proposal for 07 Series of Amendments to UN Regulation No. 105 for consideration and vote at the March 2025 sessions of WP.29 and AC.1. At the same time GRSG agreed to seek guidance through the highlights of the Chair on the deceleration value to activate the shut-off devices of hydrogen containers (paragraph 5.1.3.7.3.(b)) that could be changed by WP.15 at its November 2024 session. In this case, GRSG would request, through its Chair, to postpone the adoption of the proposal to the June 2025 sessions of WP.29 and AC.1. Moreover, GRSG noted that a proposal of a new UN Regulation for vehicles with liquid hydrogen would be developed in the framework of the activities of the Working Party on Passive Safety (GRSP). GRSG agreed that once this proposal was adopted, full alignment with UN GTR No. 13, Amendment 1 would be achieved and this new UN Regulation would be referenced in UN Regulation No. 105.