Road vehicles — Functional safety — Part 4: Product development at the system level

This document is intended to be applied to safety-related systems that include one or more electrical and/or electronic (E/E) systems and that are installed in series production road vehicles, excluding mopeds. This document does not address unique E/E systems in special vehicles such as E/E systems designed for drivers with disabilities. NOTE Other dedicated application-specific safety standards exist and can complement the ISO 26262 series of standards or vice versa. Systems and their components released for production, or systems and their components already under development prior to the publication date of this document, are exempted from the scope of this edition. This document addresses alterations to existing systems and their components released for production prior to the publication of this document by tailoring the safety lifecycle depending on the alteration. This document addresses integration of existing systems not developed according to this document and systems developed according to this document by tailoring the safety lifecycle. This document addresses possible hazards caused by malfunctioning behaviour of safety-related E/E systems, including interaction of these systems. It does not address hazards related to electric shock, fire, smoke, heat, radiation, toxicity, flammability, reactivity, corrosion, release of energy and similar hazards, unless directly caused by malfunctioning behaviour of safety-related E/E systems. This document describes a framework for functional safety to assist the development of safety-related E/E systems. This framework is intended to be used to integrate functional safety activities into a company-specific development framework. Some requirements have a clear technical focus to implement functional safety into a product; others address the development process and can therefore be seen as process requirements in order to demonstrate the capability of an organization with respect to functional safety. This document does not address the nominal performance of E/E systems. This document specifies the requirements for product development at the system level for automotive applications, including the following: — general topics for the initiation of product development at the system level; — specification of the technical safety requirements; — the technical safety concept; — system architectural design; — item integration and testing; and — safety validation. Annex A provides an overview on objectives, prerequisites and work products of this document.

Véhicules routiers — Sécurité fonctionnelle — Partie 4: Développement du produit au niveau du système

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9092 - International Standard to be revised
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ISO 26262-4:2018 - Road vehicles -- Functional safety
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STANDARD 26262-4
Second edition
Road vehicles — Functional safety —
Part 4:
Product development at the system
Véhicules routiers — Sécurité fonctionnelle —
Partie 4: Développement du produit au niveau du système
Reference number
ISO 2018
© ISO 2018
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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ii © ISO 2018 – All rights reserved

Contents Page
Foreword .v
Introduction .vii
1 Scope . 1
2 Normative references . 2
3 Terms and definitions . 2
4 Requirements for compliance . 2
4.1 Purpose . 2
4.2 General requirements . 2
4.3 Interpretations of tables . 3
4.4 ASIL-dependent requirements and recommendations . 3
4.5 Adaptation for motorcycles . 4
4.6 Adaptation for trucks, buses, trailers and semi-trailers. 4
5 General topics for the product development at the system level . 4
5.1 Objectives. 4
5.2 General . 4
6 Technical safety concept . 5
6.1 Objectives. 5
6.2 General . 6
6.3 Inputs to this clause . 6
6.3.1 Prerequisites . 6
6.3.2 Further supporting information . 6
6.4 Requirements and recommendations . 6
6.4.1 Specification of the technical safety requirements . 6
6.4.2 Safety mechanisms . . 7
6.4.3 System architectural design specification and technical safety concept . 9
6.4.4 Safety Analyses and avoidance of systematic failures . 9
6.4.5 Measures for control of random hardware failures during operation .11
6.4.6 Allocation to hardware and software .11
6.4.7 Hardware-software interface (HSI) specification .12
6.4.8 Production, operation, service and decommissioning .12
6.4.9 Verification .13
6.5 Work products .14
7 System and item integration and testing .14
7.1 Objectives.14
7.2 General .15
7.3 Inputs to this clause .15
7.3.1 Prerequisites .15
7.3.2 Further supporting information .15
7.4 Requirements and recommendations .15
7.4.1 Specification of integration and test strategy .15
7.4.2 Hardware-software integration and testing .17
7.4.3 System integration and testing .19
7.4.4 Vehicle integration and testing .21
7.5 Work products .24
8 Safety validation .24
8.1 Objectives.24
8.2 General .24
8.3 Inputs to this clause .25
8.3.1 Prerequisites .25
8.3.2 Further supporting information .25
8.4 Requirements and recommendations .25
8.4.1 Safety validation environment .25
8.4.2 Specification of safety validation .25
8.4.3 Execution of safety validation . .26
8.4.4 Evaluation .26
8.5 Work products .27
Annex A (informative) Overview of and workflow of product development at the system level .28
Annex B (informative) Example contents of hardware-software interface (HSI) .30
Bibliography .34
iv © ISO 2018 – All rights reserved

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URL: www .iso .org/iso/foreword .html.
This document was prepared by Technical Committee ISO/TC 22, Road vehicles Subcommittee, SC 32,
Electrical and electronic components and general system aspects.
This edition of ISO 26262 series of standards cancels and replaces the edition ISO 26262:2011 series of
standards, which has been technically revised and includes the following main changes:
— requirements for trucks, buses, trailers and semi-trailers;
— extension of the vocabulary;
— more detailed objectives;
— objective oriented confirmation measures;
— management of safety anomalies;
— references to cyber security;
— updated target values for hardware architecture metrics;
— guidance on model based development and software safety analysis;
— evaluation of hardware elements;
— additional guidance on dependent failure analysis;
— guidance on fault tolerance, safety related special characteristics and software tools;
— guidance for semiconductors;
— requirements for motorcycles; and
— general restructuring of all parts for improved clarity.
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