Properties of Safety Important I&C Systems and their Components - Nuclear Power Plant Instrumentation and Control Systems for Safety and Security - page 111

and controlled during the process of design,
development, manufacturing, implementa-
tion and/or commissioning:
a. Concerning cyber security of safety
I&C systems.
b. Concerning resistance and immunity
of a peripheral equipment to external
influencing factors possible in condi-
tions of design basis and beyond design
basis accidents.
2. Provision in the following standards and
regulatory documents, taking into account
native and international experience:
a. Rules for design of safety important
I&C systems, development of software-
hardware complexes, peripheral equip-
ment and software for these systems,
qualification of commercial-off-the-
shelf products and programs.
b. Methods for determination of properties
of I&C systems and their components at
all life cycle stages, assessment criteria
and rules for confirmation of compli-
ance with specified requirements.
3. Assessment of the possibility to continue
operation of I&C systems and their compo-
nents after expiration of the period specified
by manufactures:
a. Regulatory and methodological sup-
port of work, including specification
of qualification requirements.
b. Qualification tests of operational I&C
systems, software-hardware complexes
and peripheral equipment (sensors,
actuators).
c. Assessment of results of qualification
testing and decisions of continuation
of operation of I&C systems and
their components, whose properties
correspond to specified qualification
requirements.

4. Modernization of earlier developed (op-
erational) I&C systems, including replace-
ment of software-hardware complexes and
peripheral equipment, which did not pass
qualification testing, operated the with a
significant exceeding of regulated period
and / or may being a reason of unit operation
failures.

5. Improvement and adaptation of national

normative base of Ukraine, including
implementation of requirements of new in-
ternational safety standards (IAEA, 2011,a;
IAEA 2012; IEC 2011, etc.):
a. Revision and development of new
national regulations.
b. Development of standards establishing
detail technical requirements for I&C
systems and their components, as a
result of these regulations.

CONCLUSION

Properties of safety important I&C systems and
their components are determined by the require-
ments in the regulations, rules and standards of
nuclear and radiation safety, acted in Ukraine,
safety standards of IAEA and IEC,, international
industrial standards of IEC, International Special
Committee on Radio Interference, etc., as well as
state standards of Ukraine, identical with relevant
international standards.
In Chapter 3 are described properties of safety
important I&C systems and their components:

• Functional properties of I&C systems.

• Reliability of I&C functions execution

(coping with common cause failures, ob-
servance of single failure criterion, redun-
dancy, diversity principle, prevention of
personnel errors, protection from unau-
thorized access, technical diagnostic).