IEC 61839 pdf download

IEC 61839 pdf download Nuclear power plants – Design of control rooms – Functional analysis and assignment
1 Scope and object
This International Standard specifies functional analysis and assignment procedures (FAand A, sometimes called allocation of functions) for the design of the control-room system fornuclear power plants and gives rules for developing criteria for the assignment of functions.
This standard supplements lEC 60964,which applies to the design of the control-room fornuclear power plants.
The purpose of this standard is to provide specific requirements for carrying out the functionalanalysis and assignment required in 3.1 and 3.2 of lEC 60964,and therefore supersedes theguidance given in A.3.1 and A.3.2 of lEC 60964.
This standard is applicable to the design of new control-rooms or to backfits (design renewaland design modifications) to existing control-rooms. In the latter case,particular caution is tobe exercised to identify areas indirectly affected as well as those directly affected.
Normative references
The following normative documents contain provisions which,through reference in this text,constitute provisions of this International ‘Standard. For dated references,subsequentamendments to,or revisions of,any of these publications do not apply. However, parties toagreements based on this International Standard are encouraged to investigate the possibilityof applying the most recent editions of the normative documents indicated below.For undatedreferences, the latest edition of the normative document referred to applies.Members of lECand ls0 maintain registers of currently valid International Standards.
IEC 60964:1989,Design for control rooms of nuclear power plants
IEC 61771:1995，Nuclear power plants – Main control-room – Verification and validation ofdesign
3Definitions
For the purpose of this International Standard,the definitions given in IEC 60964 and thefollowing definitions apply:
3.1
accident conditions
set of conditions identified in the safety or transient analysis reports and/or in the emergencyoperating procedures
3.2
functional assignment
distribution of functions among the human and automated constituents of a system
3.3
human machine interface，HMI
interface between operating staff and l and C system and computer systems linked with theplant.The interface includes displays,controls,and the Operator Support System interface(see man/machine interface in lEc 6o964)
3.4
probabilistic risk assessment(PRA)
methodological approach to identify accident sequences that can follow from a broad range ofinitiating events; it includes the systematic and realistic determination of accident frequenciesand consequences
3.5
control function
control actions performed by humans or machines for the accomplishment of a functional goalincluding the associated information acquisition and processing 1)
3.6
tasks
control actions performed by humans for the accomplishment of a functional goal 1)
4Process of functional analysis and assignment
4.1General description
The process of functional analysis and assignment is required in clause 3 of IEC 60964 as afirst step for the design of a control-room (see figure 1). It aims initially to identify all of thefunctions required to operate the plant，then to assign the functions to humans or tomachines.