AS 61508.7-2001

1 - AS 61508.7-2001 FUNCTIONAL SAFETY OF ELECTRICAL/ELECTRONIC/PROGRAMMABLE ELECTRONIC SAFETY-RELATED SYSTEMS - OVERVIEW OF TECHN
4 - PREFACE
5 - CONTENTS
11 - 1 Scope
13 - 2 Normative references
14 - 3 Definitions and abbreviations
15 - Annex A - Overview of techniques and measures for E/E/PES: control of random hardware failures (see IEC 61508-2)
15 - A.1 Electrical
16 - A.2 Electronic
19 - A.3 Processing units
20 - A.4 Invariable memory ranges
22 - A.5 Variable memory ranges
25 - A.6 I/O-units and interfaces (external communication)
27 - A.7 Data paths (internal communication)
28 - A.8 Power supply
29 - A.9 Temporal and logical program sequence monitoring
31 - A.10 Ventilation and heating
32 - A.11 Communication and mass- storage
33 - A.12 Sensors
33 - A.13 Final elements (actuators)
34 - A.14 Measures against the physical environment
35 - Annex B - Overview of techniques and measures for E/E/PES: avoidance of systematic failures (see IEC 61508-2 and IEC 61508-3)
35 - B.1 General measures and techniques
38 - B.2 E/E/PES safety requirements specification
43 - B.3 E/E/PES design and development
47 - B.4 E/E/PES operation and maintenance procedures
50 - B.5 E/E/PES integration
52 - B.6 E/E/PES safety validation
58 - Annex C - Overview of techniques and measures for achieving software safety integrity (see IEC 61508-3)
58 - C.1 General
58 - C.2 Requirements and detailed design
75 - C.3 Architecture design
82 - C.4 Development tools and programming languages
88 - C.5 Verification and modification
100 - C.6 Functional safety assessment
105 - Annex D - A probabilistic approach to determining software safety integrity for pre-developed software
105 - D.1 General
106 - D.2 Statistical testing formulae and examples of their use
109 - D.3 References

Specifies the safety lifecycle activities in systems comprised of electrical/electronic/programmable electronic devices with an overview of various safety techniques and measures as outlined in Part 2 and in Part 3 of this Standard.

1.1 This part of IEC 61508 contains an overview of various safety techniques and measures relevant to IEC 61508-2 and IEC 61508-3.NOTE The references should be considered as basic references to methods and tools or as examples, and may not represent the state of the art.1.2 IEC 61508-1, IEC 61508-2, IEC 61508-3 and IEC 61508-4 are basic safety publications, although this status does not apply in the context of low-complexity E/E/PE safety-related systems (see 3.4.4 of IEC 61508-4). As basic safety publications, they are intended for use by technical committees in the preparation of standards in accordance with the principles contained in IEC Guide 104 and ISO/IEC Guide 51. IEC 61508 is also intended for use as a stand-alone standard.One of the responsibilities of a technical committee is, wherever applicable, to make use of basic safety publications in the preparation of its own publications. In this context, the requirements, test methods or test conditions of this basic safety publication will not apply unless specifically referred to or included in the publications prepared by those technical committees.NOTE 1 The functional safety of an E/E/PE safety-related system can only be achieved when all related requirements are met. Therefore it is important that all related requirements are carefully considered and adequately referenced.NOTE 2 In the USA and Canada, until the proposed process sector implementation of IEC 61508 (i.e. IEC 61511) is published as an international standard in the USA and Canada, existing national process safety standards based on IEC 61508 (i.e. ANSI/ISA S84.01-1996) can be applied to the process sector instead of IEC 61508.1.3 Figure 1 shows the overall framework for parts 1 to 7 of this standard and indicates the role that IEC 61508-7 plays in the achievement of functional safety for E/E/PE safety-related systems.

First published as AS 61508.7-2001.