GTB proposes simplifying UN R48 by developing a single CAD-based method to determine apparent surface at early design stages. The proposal deletes the “light-emitting surface” definition and establishes “apparent surface” as the orthogonal projection of visible light-emitting surfaces in a specified observation direction. Amendments include revised definitions for lens, textured outer lens, illuminating surface, and apparent surface, with modified requirements for single lamps with multiple distinct parts. Distance requirements between adjacent parts are adjusted to 75mm or 200mm depending on lamp type.

UN R48 baseline text for a 10 series of amendments proposes uniform provisions for vehicle lighting and light-signalling device installation approval. The document consolidates modifications agreed at working group session through dated amendment documents and resolutions. Pending issues include determining “[any] subsequent series” terminology for frozen regulations, renumbering and cross-checking paragraphs, addressing apparent surface visibility, improving daytime running lamp visibility against stop lamps, resolving “prohibited if not allowed” language, and numbering all figures with titles. Editorial polishing includes standardizing hyphenated terminology (“driving-beam,” “passing-beam,” “retro-reflector,” “direction-indicator lamp”), applying consistent UN Regulation references, replacing “communication sheet” with “communication form,” assigning table and figure numbers consistent with similar regulations, and correcting percentage notation to “per cent.”

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

This baseline draft for UN R48 (10 series of amendments) establishes uniform provisions for vehicle lighting and light-signalling device installation. The document reflects all modifications agreed at GRE-94 and incorporates an updated proposal from IEC regarding technological neutrality for LS devices. Key additions include provisions for work lamps to be included after formal WP.29 adoption in June 2026, updated tables for positioning and geometric visibility angles (Annexes 18–19), and revised terminology replacing “dipped-beam/main-beam” with “passing-beam/driving-beam” throughout. Open points address apparent surface visibility against stop lamps and consistency with IWVTA transitional provisions, with transitional provisions for the 10 series specifying acceptance dates and phase-in periods to be finalized.

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.

This document is a baseline for UN Regulation 48 (Stage 2/Step 2) concerning vehicle lighting and light-signalling devices. It incorporates all amendments from multiple series and includes provisions for adaptive front-lighting systems (AFS), driver assistance projections, reversing projections, direction-indicator projections, and automated driving system (ADS) features. The regulation establishes requirements for the design, installation, and operation of lighting devices on vehicles of categories M, N, and O, with comprehensive specifications for individual lamp types, geometric visibility angles, electrical connections, and tell-tale requirements. It includes transitional provisions allowing approvals under preceding series while establishing phased implementation timelines for new requirements.

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.