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 in Regulation 48 per SLR-75-05/Rev.1 (superseded by SLR-75-05/Rev.2), with continued discussion at SLR-76.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.

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 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 SLR experts will study the GTB draft proposal in SLR-73-04 (superseded by SLR-73-04/Rev.1) to simplify paragraphs 6.×.4.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 document considers options for the Communication form of UN R53 regarding whether to include the UN R48 series number. Option 1 retains the current form without the series number. Option 2 adopts the current Baseline document style. Option 3 adds an area in the comment section. Option 4 invites other ideas. Feedback is requested on which option should be adopted.

This document proposes draft provisions for a 05 series, updating the previous baseline (SLR-71-07). Key changes include simplification of definitions by referencing UN R48 where applicable; consolidation of geometric visibility requirements with uniform formatting; incorporation of electric vehicle (EV) provisions; inclusion of rear-end collision alert signal (RECAS); replacement of legacy terminology with hyphenated forms (e.g., “direction-indicator lamp,” “type-approved”); use of scientific notation for luminous intensity values; and reduction of transitional provisions to retain only the 05 series requirements. Annex 3 has been reserved and deleted. The regulation applies to the installation of lighting and light-signalling devices on motorcycles and prescribes mandatory and optional devices with specifications for position, geometric visibility, orientation, electrical connections, and tell-tales. Transitional provision dates remain undecided.

UN R53 series ⁰⁵ baseline amendments simplify the definition in paragraph 2 by deleting common definitions to UN R48, reducing from 49 original definitions to 27. Amendments align failure provision and EV inclusion with UN R48. The communication sheet is amended to align with UN R48. Terminology and format alignment with UN R48 and UN R74 is applied. Previous technical prescriptions are moved to a reference document, keeping only the latest. Paragraphs 6.×.4 and 6.×.5 are simplified, aligning with UN R48. An open point questions whether Annex 1 Communication form should refer to a specific Series of Amendments to R48 definitions.

This amendment modifies definitions in paragraph 2, consolidates general specifications in paragraphs 5 and 6, simplifies failure provisions, includes electric vehicles, aligns terminology with UN R48 baseline and standardizes vehicle category references to “vehicles of category(ies),” corrects AFS provision references, applies scientific notation with lumens, aligns approval number text with UN R48, corrects signal lamp category numbering, uses category symbols instead

Proposal to amend multiple paragraphs in UN R53. Changes include: paragraph 5.3. to add tolerance specifications and manufacturer fitting requirements; paragraphs 5.6.2.1., 5.6.2.2., and 5.6.2.3. to reference UN Regulation No. 48; paragraph 5.8.1. to clarify direction indicator lamp photometric characteristics; paragraph 5.19.2. regarding dual lamp assemblies marked “D”; paragraph 6.1.7.2. for HIAS failure tell-tale specifications; paragraphs 6.2.4., 6.3.3.1., 6.10.4., and 6.11.4. to define geometric visibility angles; paragraph 6.9.3. for circuit-closed tell-tale requirements; Annex 1 paragraphs 9 to 10

Proposal to correct mistakes found in the current 04 series of amendments and align with UN R48, with appropriate adaptation of L category vehicles.

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.

Based on SLR-76-03-Rev1 for R48 and tentatively applying WP.29/2024/76, IMMA presents transitional provisions for UN R53. The document outlines provisions applicable to all amendment series, including that Contracting Parties may grant type-approvals according to any preceding series and shall continue granting extensions of existing approvals. For the 05 series of amendments, specific dates establish when Contracting Parties shall accept or refuse type-approvals, with exceptions for equipment, parts, and unaffected vehicle systems.

Draft amendments to UN R53 (based on SLR-71-07, SLR-71-7, SLR-66-01, SLR-73-07, SLR-75-05, and WP.29/2024/30) updates the baseline document for the 05 series of amendments. Key changes include: simplification of definitions and general specifications; consolidation of individual specifications; addition of EV inclusion and failure provisions; editorial harmonization with UN R48 baseline regarding hyphenation, terminology, and formatting; replacement of “visual failure tell-tale” with “tell-tale indicating failure” and “rear-end collision alert signal” with RECAS; standardization of vehicle category references; adoption of scientific notation with lumens; simplification of paragraphs 6.4 and 6; and revision of the transitional provisions.

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.