The United Nations Subcommittee of Experts on the Transport of Dangerous Goods (UNSCOE TDG) is holding their 66th Session June 30 through July 4, 2025 in Geneva, Switzerland. There are 36 formal and 63 informal papers submitted for discussion as of Day 3. This session is the first of four sessions during the 2025-2026 biennium.

All daily sessions are to be held formally (interpreted). Therefore, papers are to be reviewed as listed on the agenda (INF.2) and final decisions will be taken when appropriate.

This summary is provided to assist you in following the discussions of the papers and is not intended as a full summary of the document that was presented. Links to individual papers are provided to allow you to read the papers directly. Note that the Official report of the session will be made available by the UN Secretariat 3-4 weeks after the session concludes.

Day 3 – Discussion of Papers

2025/33 (Germany, Sweden) + INF.28 (COSTHA, PRBA, RECHARGE) Clarification of special provision 405 assigned to UN Nos. 3556, 3557 and 3558 – The Subcommittee continued discussion from Day 2. Belgium commented that the images in 2025/33 represent packed articles and therefore should be regulated. They were also opposed to creating a mixed hazard communication system as presented in INF.28. Austria preferred to see the use of the Model 9A label for both large and small electric vehicles. The Netherlands and US agreed with Belgium. The UK explained that “unpackaged” is generally intended to mean “not in UN specification packaging”. Therefore, they agreed with Belgium. RECHARGE explained that the possible confusion created by the proposal in INF.28 is offset by the simple need to identify the low hazard of an electric vehicle. There is a need for hazard communication, but both the battery mark and the Class 9 label are both acceptable. The Chairman summarized by indicating there was no support for INF.28. Sweden indicated they would return later in the session with a revised proposal based on comments from the Subcommittee. No proposals were adopted.

2025/36 (Secretariat) Comments and miscellaneous proposals for amendments following the preparation of the twenty-fourth revised edition of the Model Regulations;

  • Proposal 5 – The Secretariat pointed out an editorial error in SP388 as part of the 24th Edition. The Subcommittee discussed whether the use of “vehicles and equipment” or simply “equipment” was necessary in the ninth paragraph of the special provision. After further discussion, the last sentence of paragraph 9 was revised to remove the word “equipment”.
  • Proposal 6 – The Secretariat questioned whether SP363, paragraph (f) required modification to include sodium ion batteries. The UK argued that the change seemed to assume that damaged/defective sodium ion batteries will act the same as lithium ion batteries. They preferred to delay the discussion until further data could be presented. The Chairman shared that the Subcommittee had decided to treat lithium ion and sodium ion batteries in a similar manner, and thus this is a consistency issue. Based on the discussion, the Subcommittee agreed to the proposal as drafted.

INF.27 (RECHARGE) Clarification of the requirements for the inner packaging applicable according to special provision 188 – RECHARGE asked whether SP188 permits separation in a package or whether individual cells and batteries must be completely isolated or protected in an inner packaging. They shared that images in the IATA DGR suggest that batteries may be separated by a plastic insert but did not completely enclose the cell or battery. The US believed the second image shown in the paper would provide a complete enclosure and therefore would be permitted. The UK argued that the first image showed a battery within a blister pack and was compliant. However, they opined the second image would NOT be compliant as it did not fully enclose the battery. Canada believed the intent of the provision was to prevent short circuits and therefore did not believe it was completely necessary to require an inner packaging. They suggested a review of all references in relevant special provisions and packing instructions should be reviewed. COSTHA agreed with Canada and explained there are packagings that may provide full protections without having a separate inner packaging. France recalled previous discussions on the topic and felt the text was currently acceptable. MDTC agreed with Canada and COSTHA that the issue should be further reviewed. RECHARGE indicated they would return with a formal paper to discuss the topic at a future session. No proposals were adopted.

INF.29 (PRBA, RECHARGE) Modification to Test T.2 for large batteries greater than 400 kg – PRBA explained that the size of large vehicle batteries leads to challenges with stabilizing the temperatures in the T.2 test. They offered two proposals to modify the T.2 test to address these issues. COSTHA supported the proposal and suggested this issue could be referred to the new IWG on Testing and Repair of Lithium Batteries. Germany echoed COSTHA’s proposal. PRBA indicated they would prepare a formal proposal at a future session and the issue will be referred to the new IWG. No proposals were adopted.

INF.30 (PRBA) Retesting of reused, refurbished or repaired lithium metal, lithium ion and sodium ion cells and batteries – PRBA offered a new section in 38.3.2.3 to explain how reused or refurbished batteries may or may not trigger retesting of the battery design. Given the nature of the proposal, the issue was referred to the new IWG on Testing and Repair of LB (IWGTRLB). No proposals were considered.

INF.52 (China) Lithium ion batteries testing – amendment to the T.4 shock test Informal document INF.53 (China) Definition of Lithium Battery in UN 38.3 – China noted there are no shock and pulse duration tolerances noted in T.4 test. They proposed to add them to allow clear limits on what is acceptable without compromising the results. The US supported the discussion but questioned whether this could be handled by a reference. China indicated they would refer the material to the IWG. No proposals were adopted.

INF.53 (China) Definition of lithium battery in section 38.3 of the Manual of Tests and Criteria – China described battery packs that contain independent batteries that may be utilized differently when installed in different portable equipment. They questioned whether the “pack” is considered a battery or multiple batteries in a single casing. Further, they described a battery assembly that may have connections removed in transport. Would this be considered a battery? Germany suggested the issue be referred to the new IWG for LB Hazard Classification for consideration. They pointed out this issue has implications for SP188. The Republic of Korea cautioned against the use of external switches to control electrical connections. RECHARGE argued that the difference between a group of cells and a battery is the electrical connections. Thus, a set of cells or batteries that are not connected should not be considered a battery or battery assembly. China indicated they would refer the issue to the IWG on LB Classification. No proposals were considered.

INF.21 (Secretariat) Amendments to the Model Regulations proposed by the Ad hoc Working Group on the Harmonization of RID/ADR/ADN with the UN Recommendations on the Transport of Dangerous Goods – The Secretariat provided potential changes that resulted from discussions at the Joint Meeting. They asked whether the addition of two notes to 2.9.5 as presented in Proposals 4 and 5 were appropriate. The Subcommittee believed they were appropriate for the Joint Meeting. No proposals were considered.

2025/8 (COSTHA) + INF.55 (China) Flammable gases in non-refillable pressure receptacles – COSTHA proposed to introduce a new entry for flammable refrigerants and a special provision to authorize non-refillable cylinders for gases meeting criteria for inclusion in GHS 1B or ASHREA 2L classifications. In INF.55, China questioned whether the special provision was appropriate as it referenced US DOT provisions. Instead, they suggested adding text in 4.1.6.1.9 (b). Canada supported the effort and suggested that reference to the ISO standard 1.1.1.1.8 and to use the term “test pressure” not “service pressure”. Japan and the US also supported and wished to see further specificity in the new entry description. The Netherlands cautioned the approach and use of non-refillable cylinders noting environmental concern and commented the provisions would increase the volume of cylinders x25. Austria commented they were concerned about the environmental impact of non-refillable cylinders. However, the acknowledge the challenges with impurities introduced in refilling cylinders. COSTHA thanked the Subcommittee and indicated they would work with interested parties to develop a revised proposal for the December session. No proposals were adopted.

INF.58 (China) Proposal to create a UN Number for refrigerant gas R1234yf – China proposed to create a new entry for R-1234f. They preferred to have a specific entry arguing it would provide details for modal carriers and emergency responders. The US commented that the generic approach in 2025/8 would be preferred but suggested China and COSTHA work together to provide a comprehensive solution. China indicated they would work with COSTHA on combining the discussion with the effort on 2025/8; INF.55. No proposals were adopted.

2025/4 (Germany) Marking of refillable UN pressure receptacles – closures and shells – Germany offered four (4) proposals to address cylinder requirements in 6.2.2. WLGA opposed Proposal 1 stating that there was limited space to include the new markings on existing designs. They agreed with Proposals 2-4 but recommended a transitional period where appropriate. Canada, CGA, Switzerland, and Belgium supported the proposals as drafted. Italy and France voiced opposition to Proposal 1 and requested further justification to add the marking, aligning with the comments from WLGA. Germany questioned why the marking would not fit and felt it would not be a overly burdensome approach. WLGA offered to provide examples during the next session if the decision on Proposal 1 is deferred. The Subcommittee agreed to Proposals 2, 3 and 4. Proposal 1 was also adopted but placed in square brackets for confirmation at a future session.

2025/23 (Spain) Placards on the sides of cargo transport units – Spain noted confusion between interpretations of the affixing of placards on cargo transport units between the Spanish/French and English language. In Spanish and French, the language suggested that 1 placard is required whereas each side must be placarded on each side. They offered proposals for the Spanish and French versions (Proposals 1) as well as improvements to the English version (Proposal 2). Austria supported both proposals but offered a slight modification of the wording. The UK and US supported Proposal 1 but felt Proposal 2 introduced ambiguity. Australia and Sweden preferred Proposal 2, Option 1. Canada preferred to discuss the issue further and questioned the original intent of the section, after which a revised proposal could be reviewed. China voiced support for Proposal 2, Option 1. Belgium supported Proposal 1. Switzerland opposed both proposals noting that the discussion in the Subcommittee suggested Canada’s approach was necessary. Spain indicated they would review the issue with interested proposals and return with a revised proposal. No proposals were adopted.

2025/16 (China) A revised proposal for punching holes as handles on the sides of 4G fibreboard box packagings – China explained that many packagings are designed with perforations or holes to allow ease of handling UN specification packagings. However, it is important for the regulations to clarify that when such holes are included, they must be part of the test procedures. Canada did not believe the proposal was necessary. Germany preferred to provide a more general approach to all packaging types. Sweden supported the proposal. The UK agreed with Canada and felt the proposal was superfluous but offered alternate text that would satisfy the same intent, possibly revising the definition of a package. COSTHA supported the proposal but requested the word “small” be removed. Belgium, Spain, and the US agreed that a more wholistic approach would be preferred. Based on discussion, China withdrew the proposal and indicated they would return at a future session with a revised proposal. No proposals were adopted.

2025/24 (IATA) Amendments to the preparation of packagings for testing – IATA explained the provisions of 6.1.5.2 related to the preparation of packaging for testing are confusing to review as the requirements for preparing packagings for solids and liquids are combined in the same paragraph. To improve interpretation, IATA suggested separating the text into multiple paragraphs. Germany added context for the testing requirements and suggested other sections would be impacted. China did not share IATA’s opinion and felt the current text was clear. The US and Austria viewed the proposal as editorial in nature and thus did not offer any opposition to the proposal. The UK and Belgium welcomed a review of the text as a whole but agreed with others that the justification of the proposal is not complete. They were worried that important text applied to the entire section may be lost if each paragraph is separated. IATA explained that they are aware of package testing where lead shot was substituted for liquids in glass inner packagings, which eventually led to a failure of the packaging. Based on the discussion, IATA withdrew the proposal and indicated they would return at a future session with a revised proposal. No proposals were adopted.

2025/1 (United Kingdom) Multimodal transport of portable tanks and multiple element gas containers – The UK proposed to add ISO 10855-1:2024 as an example of additional provisions that may be introduced for offshore use in 6.7.1.1. The US, the Netherlands, France, and Australia interpreted the inclusion as simply an example of what may be required and thus supported the proposal. Canada and Belgium preferred to include the reference in a note instead of regulatory text. The UK indicate they would provide an INF paper reflecting the discussion. No proposals were adopted.

2025/31 (Kingdom of the Netherlands) + INF.63 (Kingdome of the Netherlands) Transport of articles containing gas in cryogenic receptacle – The Netherlands provided a revised proposal in INF.62 to clarify how to address articles containing gas in cryogenic receptacles. The Subcommittee agreed to the proposal as drafted.

2025/25 (Russian Federation) + INF.11 (Russian Federation) Development of a new section 6.9.4 “Requirements for the design, construction, inspection and testing of portable tanks with shells made of fibre reinforced plastics (FRP) materials intended for the transport of non-refrigerated liquefied gases” – The Russian Federation presented data on prototype testing of FRP tanks for non-refrigerated liquified gases. The data was based on many discussions held at previous sessions. Models and virtual testing was prepared to show how the tanks would perform under mechanical stresses from temperature and pressure. Given the positive results of the testing, the Russian Federation requested the Subcommittee re-engage an Informal Working Group (IWG) on FRP to develop a new section 6.9.4 for the construction of FRP materials intended for non-refrigerated liquified gases. Finland supported the effort and suggested the data justified continued work in the IWG. The US requested the group discuss how the tanks will be inspected and maintained over the life of the tank but supported continued work. France also agreed to proceed with an IWG. China shared their concern that experience with FRP tanks for other dangerous goods is limited and requested delegations to share experience with the packaging. Germany and the Netherlands agreed with China but also supported the development of an IWG to discuss the issue. Canada previously shared their concerns directly with the Russian Federation but indicated they could relay these to the IWG if created. The Russian Federation offered to share a draft Terms of Reference of such an IWG, and it will be further discussed on Day 5. No proposals were adopted.

2025/36 (Secretariat) Comments and miscellaneous proposals for amendments following the preparation of the twenty-fourth revised edition of the Model Regulations – The Secretariat offered a modification in Proposal 1 related to FRP provisions in 6.9.3.5.2(d). Further, in Proposal 2, the suggested the ISO reference to ISO 14125:1998 should be updated to include “+1:2011” should be updated in 6.9.2.7.1.2, although they added a transitional provision may be necessary. The Subcommittee agreed to both proposals but added a note in the report to consider whether a transitional amendment was necessary.

2025/12 (Germany, Spain) + INF.8 (Germany, Spain) Units of measurement – Germany and Spain offered a number of editorial amendments to units for pressure, energy, work, and quantity of heat. Austria shared the original note was created during the transition from standard to metric units. The Subcommittee agreed to the proposals as drafted.

2025/17 (Sweden) Proposal for editorial amendments of 6.5.4.5.1 on repaired intermediate bulk containers – Sweden pointed out 6.5.4.5.1 refers to the definition of routine maintenance of IBCs, but note the definition needed to be updated. They proposed editorial amendments. The Subcommittee agreed to the proposals in 2025/17.

2025/36 (Secretariat) Comments and miscellaneous proposals for amendments following the preparation of the twenty-fourth revised edition of the Model Regulations – The Secretariat addressed the remaining proposals not covered during previous discussions.

  • Proposal 3 addressed deleting an outdated transitional measure in SP409. The Subcommittee adopted the proposal.
  • Proposal 4 suggested deleting a transitional measure for ISO 18119:2018. The Subcommittee adopted the proposal.
  • Proposal 7 proposed to add “also” in 6.5.5.2.8. The Subcommittee adopted the proposal.
  • Proposal 8 noted medical devices and equipment is mentioned together in 2.6.3.2.3.9 except for the last sentence. The suggested “and equipment” should be added to the last sentence. COSTHA confirmed that the omission was NOT intentional and thus was appropriate. The Subcommittee adopted the proposal.

End of Day 3 [COSTHA]