ISO 26262-10:2018

Overview

ISO 26262-10:2018 - "Road vehicles - Functional safety - Part 10: Guidelines on ISO 26262" is an informative guidance document in the ISO 26262 series. It explains the concepts, terminology and practical application of the functional safety framework for safety-related electrical/electronic (E/E) systems in series-production road vehicles (excluding mopeds and specialised single vehicles). Part 10 is intended to help organizations integrate ISO 26262 activities into company-specific development lifecycles and to improve understanding of the other parts of ISO 26262. It is guidance only; where conflicts exist, normative requirements in other ISO 26262 parts take precedence.

Key topics and technical focus

ISO 26262-10 expands on many core functional-safety subjects and provides practical explanation rather than new normative requirements:

• Functional safety concepts and relationship to IEC 61508
• Item, system and element definitions and their relationships
• Faults → errors → failures progression and timing concepts (FTTI)
• Hazard Analysis and Risk Assessment (HARA) examples and controllability classification
• Safety management, including work products, confirmation measures and functional safety assessment
• Safety cases: interpretation and lifecycle guidance
• System and concept phase guidance for safety goal derivation and external measures
• Hardware guidance: classification of random hardware faults (single-point, dual-point, residual, detected/latent classes), PMHF concepts and quantitative examples
• ASIL decomposition and examples for allocating Automotive Safety Integrity Levels
• Safety Element out of Context (SEooC) development and use-case guidance
• Proven-in-use arguments, safety-related availability and fault-tolerant design
• Software considerations, tool confidence and safety-related special characteristics
• Fault tree construction and practical applications (informative annex)

Practical applications - who uses it

ISO 26262-10 is useful for:

• Automotive OEMs and Tier suppliers implementing ISO 26262 functional safety processes
• Functional safety engineers, system architects and hardware/software developers needing practical interpretation of standard concepts
• Project managers, assessors and safety auditors preparing confirmation measures and safety cases
• Teams planning ASIL decomposition, SEooC integration, or proven-in-use justification

The guidance helps integrate functional safety into product development lifecycles, tailor the safety lifecycle for altered or legacy systems, and clarify how to handle E/E system interactions and availability requirements.

Related standards and notes

• Related: other parts of the ISO 26262 series (normative requirements)
• Cross-reference: IEC 61508 for broader functional safety principles
• Note: Part 10 is informative; when inconsistencies occur, refer to the normative parts of ISO 26262.

Keywords: ISO 26262-10, functional safety, road vehicles, HARA, ASIL decomposition, SEooC, proven in use, hardware faults, safety case, PMHF.