The document presents OICA data on rear direction indicator (DI) and stop signal visibility compliance. It evaluates various lamp configurations against UN R48 and UN R148 requirements, examining criteria including photometry areas outside 25mm from stop lamps, DI apparent surface size, separation distances, and intensity ratios. OICA proposes that compliance requirements are met when DI apparent surface equals or exceeds stop lamp surface, intensity exceeds stop lamp by 25% minimum, separation distance reaches 20mm minimum, or DI apparent surface equals or exceeds 30cm.

Proposal to amend UN R48 and UN R148 regarding direction indicator visibility when grouped with stop lamps. OICA proposes replacing Germany’s masking-based approach with objective, installation-level acceptance criteria: apparent surface area comparison, luminous intensity ratio at HV of at least 25% higher, or absolute apparent surface of 30 cm². Physical masking eliminates measurement uncertainty and improves test repeatability. Three alternative compliance routes provide flexibility without constraining designs.