40. The expert from NGV Global introduced GRSG-116-21 to amend Annex 3A of the Regulation on the design criteria and specifications for Compressed Natural Gas (CNG) cylinders with composite materials in line with standard ISO 11439. The proposal received general support. GRSG agreed to resume consideration of this subject at its next session and requested the secretariat to circulate GRSG-116-21 with an official symbol.

41. The expert from NGV Global presented GRSG-116-16 on issues associated with periodical technical inspection (PTI) and periodic requalification of CNG cylinders. The experts from Germany and United Kingdom raised concerns that PTI specifications should not be part of UN Regulation No. 110 but should be covered by the provisions of the 1997 Agreement. The Chair clarified that only a small number contracting parties to the 1958 Agreement also adhere to the 1997 Agreement (in total, thirteen contracting parties). He added that the new requirements proposed by NGV Global were mainly on inserting design requirements to ease PTI of CNG vehicles in service. GRSG agreed to defer discussion on this subject to its next session. The Chair invited all interested experts to send their comments in due time to the NGV Global expert to allow him to prepare a revised proposal for consideration at that session as an official document.

42. The expert from Italy presented GRSG-116-18 showing the benefits and construction principles of conformable storage concepts for future CNG vehicles. He introduced GRSG-116-17 that proposes to amend UN Regulation No. 110 to allow such storage for agricultural and commercial vehicles. GRSG experts welcomed the initiative of Italy. The Chair invited all interested stakeholders to send their comments in due time to the expert from Italy. GRSG agreed to resume consideration of this subject at its next session based on a revised proposal by Italy, to be circulated as an official document.