IEC 61069-7:1999 pdf download – lndustrial-process measurement and control-Evaluation of system properties for the purpose of system assessment – Part 7: Assessment of system safety

IEC 61069-7:1999 pdf download – lndustrial-process measurement and control-Evaluation of system properties for the purpose of system assessment – Part 7: Assessment of system safety.
This part of lEG 61069 describes In detail the method to be used to systematically assess the safety property of an industrial-process measurement and control system.
The treatment of safety In this standard is confined to hazards that can be present within the industrial-process measurement and control system Itself. Considerations of hazards that can be introduced by the process or equipment under control of the industrial-process measurement and control system to be assessed are excluded. If the system mission includes activities which could affect the safety of the process or equipment under control, the requirements of these activities are the subject of lEG 61508.
2 Normative references
Tho following normative documents contain provisions which, through reference In this text. constitute provisions of this part of IEC 61069. For dated references, subsequent amendments to. or revisions of. any of these publications do not apply. However, parties to agreements based on this part of IEC 61069 are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of IEC and ISO maintain registers of currently valid International Standards.
lEG 61010-1:1990 Safety requirements for electrical equipment for measurement, control and laboratory use — Part 1 General requirements
IEC 61069-1:1991, lndustriat.pi’ocess measusmert and control – Evaluation of system properties for the purpose of system assessment — Part 1: Genera’ considerations and methodology
IEC 61069-2:1993, lriduslriat-process measurement and control — Evaluation of system properties for the purpose of system assessment — Part 2: Assessment methodology
IEC 61069-5:1994, lr?duslrlal.process measurement and control — Evaluation of system properties for the purpose of system assessment — Part 5: Assessment of system dependability
IEC 61508-1.— Functional safety — Safety-related system — Part 1: General requirements 2) ISOIEC Guide 51:1990. Guidelines for the inclusion of safety aspects in standards
3 Definitions
For the purpose of this part of lEG 61069. the following definitions apply:
3.1
system gaiety
extent to which the system itself as a physical entity will not impose a hazard
NOTE — System satety does not Include the safety of tile process or equipment under control. The satety of the process at eqtapmenl undef control *ill rely upon the dependability 04 the system if the system is used to perform safety functions (r.t.t to lEG 615081
3.2
hazard
polential source of harm (ISO/IEC Ouide 51:1990. definition 3.3)
3.3
harm
physical injury and/or damage to health or property (ISO/IEC Guide 51:1990. definition 3.4)
4 Safety property
4.1 General
A system can have a number of interactions with its environment, some of which can impose a hazardous condition.
This standard concentrates on the conditions of the system which can cause a hazard. It is important to recognize that these conditions can change over the lifetime of the system.
The extent to which the system is free of hazard can be expressed as the system safety properly. A system may not be free ol hazard even it the individual elements that compose the system are themselves free of ha.zard: for example, individual elements can be stable whereas the same elements configured to form a system can be unstable end therefore hazardous.
The sat ely property of an industrial-process measurement and control system in all its aspects (mechanical, electrical, etc.) depends upon factors such as the inherent safety of its design and its dependability (see lEG 61069-5). The assessment of the system safety shall cover all activities related to the system during the installation, operational. de.commlssloning and disposal phases of its life cycle. It shall also include all environmental aspects. During each of the phases, at least the following measures and activities are to be considered.