ISO/PAS 21448

Paper proposes Transferability and Predictability metrics to extend ISO 26262 for autonomous vehicles

A preprint from arXiv proposes decomposing the ISO 26262 'Controllability' concept into two measurable sub-dimensions—Transferability (AV handoff to fallback mechanisms) and Predictability (external agents' ability to anticipate AV behavior)—to make functional safety standards applicable to driverless SAE Level 4/5 systems. The authors provide a mathematical framework for quantifying Predictability and introduce a designed-versus-achievable gap to distinguish architectural claims from scene-conditioned fallback capability. The proposed metrics are designed to align with both ISO 26262 and ISO/PAS 21448 (SOTIF), making safety claims falsifiable and traceable across operational design domains.