IEC 61559-2:2002 pdf download

IEC 61559-2:2002 pdf download.Radiation in nuclear facilities –
Centralized systems for continuous monitoringof radiation and/or levels of radioactivity -Part 2: Requirements for discharge, environmental,accident, or post-accident monitoring functions.
1.4 Terminology
The general terminology concerning detection and measurement of ionizing radiation and nuclear instrumentation is given in IEC 60050-393, IEC 60050-394, IEC 60181 and IEC 60181A. Specific terminology for centralized systems for continuous monitoring of radiation is given in IEC 61559.
For the purpose of this part of IEC 61559, the following definitions apply.
1.4.1
category B classification
this classification is derived from IEC 61226.
Category B is used to denote function and associated systems and equipment (FSE) which play a complementary role in the achievement or maintenance of nuclear safety. Category B includes FSEs whose failure could initiate an event that could lead to an anticipated operational occurrence (AOO) or accident. Category B also includes FSEs whose failure could worsen the severity of an AOO or accident. More specifically, category B FSEs are defined as relevant to:
• maintaining process variables within the limits assumed in the safety analysis;
• preventing or mitigating minor radiation releases; and
• considerably reducing the frequency of an initiating event as claimed in the safety analysis.
1.4.2
operator console (OC)
it displays system or subsystem data to plant operators and is the operator control interface through which operators request information, input information, and perform control functions. Operator consoles typically incorporate a video display unit (VDU) as indicated in IEC 61559.
NOTE This part of IEC 61559 uses the more general term “operator console” to make clear the intent that other types of user interfaces are allowed. A centralized radiation monitoring system (RMS) will have at least one CC. RMS CC functions may be incorporated into the CC functions of a more general purpose display.
1.4.3
functions and the associated systems and equipment (FSE)
functions are carried out for a purpose or to achieve a goal. The associated systems and equipment are the collections of components and the components themselves that are employed to achieve the functions (see IEC 61226, clause 3).
1.5 Test nomenclature
Specific terminology for centralized systems for continuous monitoring of radiation are given in IEC 61559. The term “acceptance test” defined in IEC 61559 is used here in two senses.
1.5.1
acceptance tests
contractual tests to prove to the customer that the device meets certain conditions of its specification [1EV 151-04-20]
NOTE These tests may take place within the factory or within the customer’s site
1.5.2
commissioning tests
tests to demonstrate that the system as installed in the facility meets certain conditions of its specification
Below are the design requirements in the order they are listed in IEC 61559. For some design topics this standard imposes no additional design requirements beyond those stated in IEC 61559:1996. For other design topics, additional requirements are described below.
2.1 General remarks
2.1.1 Introduction
IEC 61559 discusses the types of monitoring provided by centralized systems for continuous monitoring of radiation in nuclear facilities. The scope of this part includes the following additional functions:
— activation of control and protection functions to support normal operation of systems, response to incidents, and prevention or mitigation of releases during and following accidents;
— monitoring of plant discharges;
— interlock of control functions;
— environmental monitoring.
2.1.2 Safety classification
It is expected that some equipment covered by this standard would be classified as category B per the definitions of IEC 61226 as well as category C as discussed in IEC 61559.
Where the RMS supports functions of another system, the RMS FSE shall be classified at the same level as the supported function.
2.1.3 System configuration
No requirements beyond IEC 61559 are necessary.
2.1.4 Location of detector subassemblies
No requirements beyond IEC 61559 are necessary.
2.2 Design requirements for the subassemblies
2.2.1 Detector subassembly
No requirements beyond IEC 61559 are necessary.
2.2.2 Processing unit
2.2.2.1 General.