The GRE Informal Working Group on Simplification of UN Lighting and Light-Signalling Regulations held its 73rd session in Brussels on 9-11 July 2025. SLR approved reports from the 70th and 71st sessions. The Homework Team R-150 will prepare an updated version of SLR-73-09 including a decision tree and justification for submission to GRE-93 or GRE-94. SLR experts will study the GTB draft proposal in SLR-73-04 (superseded by SLR-73-04/Rev.1) to simplify paragraphs 6.×.4. and 6.×.5. in Reg. 48. SLR-73-07/Rev.1 reflects the latest baseline document for Reg. 48 with agreed modifications. IMMA introduced baseline documents for Reg. 53 and Reg. 74 reflecting simplified definitions. CEMA will prepare a baseline document for Reg. 86. GTB will prepare an updated proposal for a CAD-based method to determine apparent surface for SLR-74. A special SLR session on apparent surface may be held on 10 September 2025 if equipment is available. Discussion continues on harmonisation of requirements, improving direction indicator visibility, and technological neutrality for light sources. The 74th SLR meeting is scheduled for 10-12 September 2025 in Brussels.

The 74th SLR meeting (Brussels, 10–12 September 2025) reviewed baseline documents for Regulations 48, 53, 74, and 86, with participants improving draft texts on simplified paragraph structures and definitions. Key topics included correction of errors in Regulation 150 (formal proposal for GRE-94 April 2026), apparent surface simplification with support for Alternative A and luminance method consideration, improved visibility of daytime running lights (OICA drafting proposal for December session), and harmonisation of requirements regarding prohibited if not allowed (seeking GRE feedback). Technological neutrality for light sources was deferred to informal discussions. The 75th meeting is scheduled for 10–12 December 2025 in Brussels.

The GRE Informal Working Group on Simplification of UN Lighting and Light-Signalling Regulations held its 75th session in Brussels, 10–12 December 2025. SLR reviewed and improved revised baseline documents for Regulations 48, 53, 74, and 86, reflected in SLR-75-10/Rev.1, SLR-75-16/Rev.1, SLR-75-17, and SLR-75-21 respectively. SLR endorsed corrections to Regulation 150-01 in SLR-75-02/Rev.1 and simplified paragraphs 6.×.4. and 6.×.5. in Regulation 48 per SLR-75-05/Rev.1 (superseded by SLR-75-05/Rev.2), with continued discussion at SLR-76. SLR tasked GTB to complete work on apparent surface definition and CAD method. SLR agreed the 76th meeting will be held 4–6 February 2026 in Brussels.

Proposal for supplement to the 01 series of amendments to UN Regulation No. 150, amends SLR-78-07/Rev.1. Proposal to reduce the number of samples required for approval from ten to eight, delete references to colour-fastness testing and weathering resistance testing from paragraph 3.5.3.1., amend paragraphs 5.1.2., 5.1.3.1., and 5.1.7. to reflect the reduced sample requirement and revised test protocol, replace “light emitting surface” with “illuminating surface” in Annex 5, amend Annex 7 paragraph 1.1. to replace “apparent” with “noticeable” when describing surface changes, delete columns i and j and associated test rows from Tables 4 and 5, and delete Annex 11 Guidelines for installation of rear marking plates on slow-moving vehicles.

Proposal to amend approval marking and Unique Identifier requirements:

• Clarify conditional requirements for approval markings and Unique Identifier usage in the Introduction,
• Delete paragraph 3.3.3. on Unique Identifier provisions,
• Renumber paragraphs 3.3.4. through 3.3.6. as 3.3.3. through 3.3.5.,
• Amend paragraphs 3.3.1.1., 3.3.1.3., 3.3.5. and sub-paragraphs, and 3.3.6. and sub-paragraphs to remove references to Unique Identifier and reorganize marking requirements,
• Add new paragraph 3.3.2.5. requiring a downward arrow for devices with reduced light distribution,
• Amend paragraph 5.1. to expand class specifications from IA and IB to IA, IB, IIIA, IIIB and IVA,
• Restructure paragraph 5.1.3.1. testing procedures with new sub-paragraph 5.1.3.1.1. for Classes IA, IB, IIIA and IIIB and new paragraph 5.1.3.1.2. for Class IVA specifying distinct sample groupings,
• Amend paragraph 5.1.7. to create separate Tables 4 and 5 for chronological test orders for Classes IA, IB, IIIA, IIIB and Class IVA respectively,
• Amend paragraphs 5.2.3.3., 5.2.5.1.1., 5.2.5.2.1., 5.2.6.3., 5.2.6.4., and 5.3.4.2.,
• Insert new Table 8 with chromaticity coordinates and luminance factor requirements for Classes 1, 2, 3 and 4,
• Renumber existing Tables 8, 9 and 10 as Tables 9, 10 and 11,
• Amend paragraph 5.3.5.2.2.,
• Delete paragraph 5.2.5.2.1.,
• Amend Annex 1 Item 5. and para. 10 to remove Unique Identifier references,
• Amend Annex 5 paragraph 8.1.4.,
• Amend Annex 6 Part 2 paragraphs 1.3.2. and 2.1.3. and Part 4 paragraph 4.2.,
• Amend Figure A10-1 in Annex 10 to clarify marking arrangement requirements and remove diametrically opposite placement requirement for class symbols.

Proposal to amend para. 3.5.3.1. to delete reference to colour verification of retro-reflecting optical units, amend para. 5.1.2. to reduce required samples from ten to eight, amend para. 5.1.3.1. to reduce samples from ten to eight and divide remaining six samples into three groups of two, insert para. 5.1.3.1.1. specifying Classes IA, IB, IIIA and IIIB, amend para. 5.1.7. to delete sample columns i and j from Tables 4 and 5 and delete the weathering resistance test row, and amend reference to Part 4 of Annex 6 to Part 5 of Annex 6 in both tables.

Proposal to amend UN R86 on approval markings and testing requirements:

• Delete provisions regarding the Unique Identifier and conditional use of conventional type approval markings from the Introduction
• Amend para. 3.3.1.1. to delete reference to the Unique Identifier
• Amend para. 3.3.1.3. regarding approval marking proportions
• Add new para. 3.3.2.5. requiring a vertical downward arrow for devices with reduced light distribution
• Delete para. 3.3.3. on Unique Identifier entirely
• Renumber para. 3.3.4. as 3.3.3.
• Renumber para. 3.3.5. as 3.3.4. and amend to delete reference to Unique Identifier
• Renumber para. 3.3.6. as 3.3.5. and amend to delete reference to Unique Identifier
• Amend para. 5.1. to include Classes IIIA, IIIB and IVA
• Amend para. 5.1.3.1. regarding heat resistance testing and divide samples into groups for testing Class IA, Class IB, Class IIIA and Class IIIB
• Add new para. 5.1.3.1.2. for Class IVA testing
• Amend para. 5.1.7. to create separate Tables 4 and 5 for chronological order of tests for Classes IA, IB, IIIA, IIIB and Class IVA respectively
• Amend para. 5.2.3.3. to reference Part 1 of Annex 6 and paragraphs 5.2.5. and 5.2.6.
• Amend para. 5.2.5.1.1. regarding coefficient of retro-reflection measurement
• Delete para. 5.2.5.2.1. entirely
• Amend para. 5.2.6.3. to include colour requirements and insert Table 8
• Amend para. 5.2.6.4. regarding luminance factor
• Renumber Tables 8, 9 and 10 as Tables 9, 10 and 11
• Amend para. 5.3.5.2.2. to reference Table 11
• Amend Annex 1 Item 5. and delete reference to Unique Identifier in Item 10
• Amend Annex 5 para. 8.1.4. to correct cross-reference to para. 5.3.4.2.1.
• Amend Annex 6 Part 2 para. 1.3.2. to reference para. 5.2.5.1.
• Amend Annex 6 Part 2 para. 2.1.3. to correct paragraph references
• Amend Annex 6 Part 4 para. 4.2. to reference Table 6 only
• Insert new Part 7 in Annex 6 on colour-fastness for Classes IA, IB, IIIA, IIIB and IVA
• Amend Figure A10-I to clarify marking arrangement rules and delete the diametrically opposite requirement

Amend para. 5.1.2. to change the number of samples from ten to eight, modify para. 5.1.3.1. to reduce samples from ten to eight and divide the other six samples into three groups instead of four by deleting the fourth group colour-fastness test requirement, add para. 5.1.7. specifying the chronological order of tests in tables for Classes IA, IB, IIIA, IIIB and Class IVA, and amend para. 3.5.3.1. to add provisions for verification of stability in time of optical properties and colour of retro-reflecting optical units of advance warning triangles in use and withdrawal of approval for systematic deficiencies.

Proposal to amend paragraph 5.2.3.3 to clarify that samples shall be subjected to the heat resistance test described in Part 1 of Annex 6, prior to the tests described in Parts 1 and 2 of Annex 6 paragraphs 5.2.5 and 5.2.6. Proposal to amend paragraph 5.1.7 to correct the reference in Tables 4 and 5 from Part 4 to Part 5 of Annex 6 for the Rear face test. Proposal to amend Annex 5, paragraph 8.1.4 to correct the cross-reference from paragraph 5.9.4.2.1 to paragraph 5.3.4.2.1.

The agenda includes corrections to UN R150-01, baseline documents for UN R53, R74, R86, and R48, simplification of paragraphs 6.×.4 and 6.×.5, transitional provisions, harmonisation of requirements, apparent surface considerations, and direction indicator visibility improvements. The next meetings are scheduled for June and December 2026, with a potential September 2026 session in Tokyo.

SLR-76 session documents are available on the SLR website. Actions include: correcting errors in UN R150 for submission to GRE-94; preparing Stage 2/Step 2 baseline documents for UN R48, R53, R74, and R86; finalizing simplification of paragraphs 6.×.4 and 6.×.5; discussing apparent surface methodology; approving technological neutrality amendments to UN R48 and R149; collecting literature on rear direction indicator visibility; and reviewing harmonization requirements. SLR-77 meeting scheduled April 15-17, 2026 in Brussels.

Proposal to correct errors and omissions in the 01 series of amendments. Further details can be found in informal document GRE-94-02.

Proposal to amend UN R150-01 addressing three main issues. First, since the GRE-adopted proposal to delete the unique identifier (GRE-92-18) was not part of the March 2026 WP.29 submission, the regulation text requires amendment in the interim, though this may become unnecessary if merged with GRE-92-18. Second, the approval marking approach is aligned with UN R148 by including one example in the body text and referencing other arrangements in Annex 10, allowing deletion of the Table 1 reference and redundant ratio explanations from Figure A10-I. Third, the outdated requirement for function symbols to be placed diametrically opposite the approval number — inherited from UN R3 and R7 but already removed in UN R148 — is deleted from Annex 10, along with a clarifying amendment to the note below Figure A10-I to prevent inconsistent interpretations among technical services. Further details can be found in informal document GRE-94-11.