Organization and Information Support of Expert Reviews of I&C Systems Modernization at NPP of Ukraine - Nuclear Power Plant Instrumentation and Control Systems for Safety and Security - page 375

specific reactor type) and replicated (moderniza-
tions implemented before at a specific NPP type in
Ukraine and showed positive results). Of course,
use of replicated systems is preferable in terms of
safety justification and cost for acquisition of sys-
tems. The scope of licensing actions for replicated
modernizations is substantially smaller than for
pilots. A specific stage in the implementation of
a pilot system is its trial operation with extensive
support from the designer and prompt feedback
from the NPP to the designer, involving analysis
of all failures, faults or NPP personnel comments.
At this stage operator develops technical de-
cision on putting of the modification object into
trial operation.
According to GOST, 1992,a trial operation is
performed to define actual knowledge of quantita-
tive and qualitative characteristics of the I&C sys-
tems and personnel readiness to work in operation
conditions of the I&C systems, to define actual
I&C systems efficiency and for documentation
correction (if necessary).
To substantiate the safety under putting of the
modification object into trial operation the follow-
ing documents are attached to technical decision:

• Program of trial operation of modiication

object;

• Program and methods of acceptance testing

of modiication object (can be submitted
later, but under the condition of approval
by the beginning of acceptance testing).

According to results of trial operation a deci-
sion of possibility of submission parts of the I&C
systems and the system in a whole for acceptance
testing is made. The work is finished with draw-
ing up an act of completion of trial operation and
system allowance for acceptance testing.

Stage 6: Putting of I&C systems into stationary
operation at NPP.

After successful completion of trial operation,
a technical decision on putting of the modification
object into stationary operation is developed for
implementation and a task for putting modification
object into stationary operation as a part of NPP
is agreed with the regulatory authority.
To substantiate the safety under putting modifi-
cation object into stationary operati at NPP, attach
the following documents to technical decision:

• Report or other documents (act, proto-

cols) containing results of assembling and
commissioning;

• Report or other documents (act, protocols)
containing results of trial operation;
• Act and protocols of acceptance testing
and other materials of interauthority ac-
ceptance commission;

• Report on results of preliminary complex

testing of modiication object within NPP,
submitting protocols and acts of testing
execution; • Final safety analysis report improved ac-

cording to results of trial operation; • Information about results of metrological

test of measuring lines (if any); • Information about application of changes

into design and operational documentation; • Information about personnel training in-

volved into modiication object operation; • Information about results of metrologi-

cal certiication of measuring tools (if
required).

• Information about applied temporary

changes into design and operational
documentation;