The 78th session of the GRE Informal Working Group on Simplification of UN Lighting and Light-Signalling Regulations was held in Brussels, 10-12 June 2026. SLR decided not to include a new Part 7 on Colour-fastness in Annex 6 to Regulation 150-01 and will submit a consolidated correction proposal to GRE-95. Discussion on apparent surface definitions and single lamp distance requirements will resume at SLR-79, with wider consideration of related topics including glare and direction indicator visibility. Baseline documents for Regulations 48, 53, 74, and 86 were reviewed and updated versions will be prepared for the next session. The next SLR meeting will be held in Tokyo on 7-11 September 2026.

This document discusses single lamp distance requirements in context of Apparent Surface simplification pursuant to discussions with Contracting Parties. The current 75mm separation value was not based on studies but on considerations. A 1999 IENGF Milano study concluded that larger distances are acceptable for symmetric constellations, with AFS lighting units spaced up to 200mm. A minimum 600mm separation is mandatory if right and left mounted functional unit identification is required. No evidence of increased accident risk, misidentification of signal, reduced conspicuity, or regulatory enforcement issues from current single lamp separation distances exists. The simplified CAD-based Apparent Surface concept will be based on light emitting surface with clear outer lens disregarded. GTB suspended work on this topic due to insufficient consensus and difficult stakeholder alignment, pending additional information on single lamp separation distance.

At the 77th SLR meeting (Brussels, April 2026), participants reviewed and improved baseline documents for UN Regulations 48, 53, 74, and 86, reflected in SLR-77-08/Rev.1, SLR-77-09, SLR-77-10, and SLR-77-07 respectively. SLR approved a revised proposal to correct errors in Reg. 150-01 (SLR-77-06/Rev.1, superseding GRE-94-02) and a compromise text prohibiting additional lamps unless complying with national requirements. SLR agreed to postpone official document submission to GRE-96 (April 2027) and will submit 11 informal documents to GRE-94, including status report, four baseline documents, four highlights slides, a proposal on technological neutrality, and the revised correction proposal. Discussions on apparent surface, direction indicator visibility, and direction indicator lamp height will resume at SLR-78 (June 2026).

Proposal to amend UN R53:

• Simplify para. 2 by deleting vehicle type definition and consolidating definitions from UN Regulation No. 48,
• Consolidate para. 5 general specifications by reorganising lamp positioning requirements into para. 5.5. and 5.6., restructuring geometric visibility provisions, and clarifying electrical connections,
• Consolidate para. 6 individual specifications by standardising positioning formats into minimum/maximum height tables and reformatting geometric visibility angles into upwards/downwards/outwards/inwards notation,
• Delete para. 5.20. as its content moves to para. 5.6.,
• Delete Annex 3 as its content references UN Regulation No. 48,
• Simplify transitional provisions by deleting para. 11.1. through 11.11. and para. 11.12. and replacing with new para. 11.1. and 11.2. containing simplified provisions applicable to the 05 series of amendments with dates to be determined (1 September 20xx),
• Add Annexes 10 and 11 containing summary tables of lamp positioning and geometric visibility angles.

The 76th SLR session (4–6 February 2026) reviewed and improved baseline documents for Regulations 48, 53, 74, and 86 for Stage 2/Step 2 submission to GRE-94 as informal documents. SLR approved simplification of paragraphs 6.×.4. and 6.×.5. in Reg. 48 and agreed on technological neutrality amendments to Reg. 48 and a compromise text for Reg. 149. SLR approved a compromise text on “Prohibited if not allowed” for final check at SLR-77. Discussions on apparent surface and direction indicator visibility will resume at SLR-77. Transitional Provisions for the 10 series will be reviewed at SLR-77. The 77th, 78th, and 79th meetings are scheduled for April, June, and September 2026.

The agenda includes adoption of previous session reports, correction of errors in Regulation 150-01, improvement of direction indicator visibility, rearrangement of lamp provisions in Regulation 48, consistency checks for geometric visibility angles, baseline documents for Regulations 48, 53, 74, and 86, review of transitional provisions, discussion of apparent surface definitions, and submission preparation for GRE-95.

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.

The 79th SLR Informal Working Group Meeting will be held 7–11 September 2026 at AP Ichigaya, 8th Floor, AP Ichigaya, Ichigaya Osato Building, 1–10 Gobancho, Chiyoda-ku, Tokyo 102–0076, Japan. A reception is scheduled for 9 September 2026 at 18:00–20:00. The meeting includes sessions on Task Force on Glare Prevention and Task Force on Lamps Under Parked Conditions and Task Force on Autonomous Vehicle Signalling Requirements, though it has not yet been decided whether the latter two task forces will be held during the Tokyo meetings. Participants should complete the registration form.

The agenda addresses correction of errors and omissions in UN Regulation 150-01, including a consolidated proposal merging GRE-92-18, GRE-94-02/Rev.1, GRE-94-11, and GRE-94-24, and a decision on addition of Part 7 on Colour-fastness to Annex 6. Baseline documents for UN Regulations Nos. 48, 53, 74, and 86 will be reviewed, along with transitional provisions. The group will consider visibility of direction indicators and Korean concerns regarding rear direction indicator lamp height. The 79th meeting is scheduled for Tokyo in September 2026.

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.

Proposal to amend, restructure, and clarify UN R86:

• Update the regulation title and scope to reference vehicles of category T, R, S, agricultural and forestry NRMM vehicles regarding installation of lighting and light-signalling devices
• Restructure and reorganize para. 2 (Definitions) by consolidating lamp definitions, deleting outdated definitions, and reorganizing vehicle-related and lamp-related definitions into separate sections
• Revise para. 3 (Application for approval) to clarify submission requirements and add reference to Annex 1 documentation
• Amend para. 4 (Approval) to reference Schedule 4 of the 1958 Agreement and update approval mark procedures in Annex 2
• Restructure para. 5 (General specifications) by reorganizing and renumbering provisions relating to lamp position (para. 5.5.), geometric visibility (para. 5.6.), single lamps (para. 5.9.2.), tell-tale requirements (para. 5.14.), concealable lamps (para. 5.15.), and lamps of variable position (para. 5.17.), and revise provisions regarding electrical connections for front and rear position lamps, driving-beam and passing-beam headlamps, and daytime running lamps
• Restructure and revise para. 6 (Individual specifications) by introducing para. 6.0. as a general introductory provision, renaming driving-beam and passing-beam headlamps throughout, reorganizing direction-indicator lamp arrangements as A, B, C, D, E with detailed geometric visibility specifications in para. 6.5.5., revising stop lamp position and geometric visibility requirements in para. 6.7., restructuring front and rear position lamp requirements, revising rear fog lamp electrical connections, clarifying parking lamp requirements, restructuring rear and front retro-reflector specifications to include separate sections on electrical connections, tell-tale, and other requirements, reorganizing side-marker lamp provisions, clarifying conspicuity marking requirements, revising SMV rear marking plate specifications, restructuring exterior courtesy lamp and manoeuvring lamp requirements, and updating all light colour specifications
• Amend para. 8 (Conformity of production) to include reference to the Agreement Schedule 1 and clarify the conformity requirements
• Clarify para. 10 (Production definitively discontinued) regarding notification requirements
• Revise para. 12 (Transitional provisions) to replace existing series-specific provisions with general transitional provisions applicable to all series of amendments and add new transitional provisions for the 04 series of amendments with dates specified as 1 September 20xx (pending confirmation)
• Update Annex 1 (Communication) to reference the 04 series of amendments in the approval mark examples and add informative tables (TableA4-1 and TableA4-2) in Annex 4 (previously Annex 3) summarizing lighting and light-signalling installation rules for tractors/agricultural and forestry NRMM (vehicles of category T) and vehicles of categories R and S
• Revise Annex 2 (Examples of arrangements of approval marks) to reference the 04 series of amendments and update marking examples
• Delete Annex 3 (The relevant parts of Annex 3 to UN Regulation No. 48 apply) and replace with visibility zones diagrams in new Annex 3
• Reorganize former Annex 5 (Direction-indicator lamps – Geometric visibility) and incorporate into new Annex 4 as summary tables with footnotes explaining special conditions
• Update Annex 5 (Signalling panels and signalling foils) to clarify dimensions, arrangement, number and reflecting surface requirements with references to updated figures and table

The document addresses simplification of the definition of “apparent surface” and single lamp distance requirements in UN R48. It presents a new CAD-based concept defining apparent surface using light emitting surface with clear outer lens disregarded. The document notes that current regulation allows multiple ways to define apparent surface resulting in different distances, with existing approvals having distances significantly larger than 75mm between distinct parts without known safety issues. GTB agrees on simplifying the apparent surface definition to describe function contours as seen by road users, while acknowledging this should not restrict possible designs. The document references a 1999 INF Milano study concluding symmetric appearance is relevant for vehicle identification and larger distances are acceptable for symmetric compared to asymmetric constellations.

OICA opposes introducing a regulatory requirement for horizontal adjustment of passing-beam/driving-beam and for AFS/ADB to the current SLR agenda. The proposal does not contribute to simplification of lighting regulations, no identified safety concern or ambiguity justifies this requirement, and it lacks a formal proposal from a Contracting Party, NGO, or other stakeholder. The SLR group is managing several longstanding unresolved issues, and introducing this topic risks further delaying progress. Harmonized requirements require comprehensive understanding of Periodic Technical Inspection specifications across all Contracting Parties, which are currently unavailable.

Proposal for editorial work with thorough review and consistency improvements. New informative Annexes for lamp positioning and geometric visibility angles are added. Technical prescriptions now pertain only to the new series. Light source provisions are clarified regarding technological neutrality, usage of light source modules, and non-replaceable light sources.

Proposal applies to vehicles of categories T, R, and S and agricultural NRMM regarding lighting and light-signalling device installation. The regulation establishes approval procedures, general specifications for lamp fitting and adjustment, electrical connections, and individual specifications for various lighting functions including driving-beam and passing-beam headlamps, direction-indicator lamps, stop lamps, position lamps, retro-reflectors, and other light-signalling devices. It specifies position requirements (height, width, length), geometric visibility angles, colour requirements, and electrical interconnection rules. Transitional provisions address implementation across different amendment series, with staggered acceptance periods for type-approvals granted under preceding series of amendments.

UN R86 baseline amendments add agricultural non-road mobile machinery to scope. Definitions are simplified by removing common vehicle definitions and aligning structure with UN R48. Headlamps symmetrical classes are reviewed following CLEPA comment. Side retro-reflector requirements align with EU requirements on location. Direction-indicator lamps alignment with EU scope for tractors remains an open point.

Proposal to amend the definitions ; add EV inclusion; clarify individual and general provisions, failure provisions, and transitional provisions; correct signal lamp category; use category symbol instead of lamp function name;

Proposal to amend UN R74 series 04 by simplifying the definition in paragraph 2 through deletion of common definitions to UN R48, applying amendments for failure provision and EV inclusion, aligning terminology and format with UN R48 and UN R53, retaining only the latest transitional provisions, simplifying paragraphs 6.×.4 and 6.×.5, and providing editable pictures.