Proposal to harmonize UN R110 with standard ISO 11439:2013 on high pressure cylinders for the on-board storage of natural gas as a fuel for automotive vehicles.

Proposal to allow the use of Class 0 hoses with couplings using sealing technologies other than those with a 45° cone. Currently, non-seamless double and single wall tubes are used in brake and fuel tubing applications, allowing for the use of a variety of end forms and coupling techniques. Provided the hose assembly can withstand the impulse test of paragraph 1.7. and the tests of Annexes 5A (overpressure test) and 5B (external leakage test), such configurations should be permitted under UN R67 in order to remove an unwarranted design restriction. In cases where a soft seal body (e.g. O-ring) is used, the compatibility of the material with use conditions must be demonstrated by testing according to Annexes 5D (CNG/LNG compatibility test), Annex 5F (resistance to dry heat) and Annex 5G (ozone aging).

Proposal to correct a typographical error in paragraph 7.1. where the reference should be to paragraph 8.22 rather than 8.21, to remove a duplicate and contradictory reference in Annex 4A to the requirements of Class 1 pressure relief valves, and to align paragraph 2.2. of Annex 4H with paragraph 18.6.1.2. limiting the delay in switching-off of the automatic valve after stalling of the engine to two seconds (rather than five as presently in the text).

Proposal to include the liquefied natural gas (LNG) fuel connector provisions as specified in ISO 12617:2015.