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NuclearPlantJournal.com Nuclear Plant Journal, March-April 2016
Recommended Practice for Seismic
Qualification of Class 1E Equipment for
Nuclear Power Generating Stations" in its
various versions) and CGD are distinct
and not intended for the same purposes.
The
purpose
of
equipment
qualification is to generate and to
maintain “evidence to ensure that
equipment will operate on demand to
meet system performance requirements
during normal and abnormal service
conditions and postulated design basis
events.” Furthermore, these standards are
intended to establish the requirements
that “when met, demonstrate and
document the ability of the equipment
to perform safety function(s) under
applicable service conditions including
design basis events, reducing the risk of
common-cause equipment failure.” In
other words, qualification is an activity
undertaken to verify that a component’s
design is suitable for the intended nuclear
power plant or nuclear processing facility
application.
Dedication is an acceptance
process. This process is used to provide
a reasonable assurance that the item
supplied can perform the same safety
function(s) as the design that was
qualified. The suitability of the design
must be established prior to procurement
of an item and dedication cannot be
used as a substitute for design, change
the design or as a means to verify the
suitability of a design.
5.
Has AREVA process been accepted
by US NRC?
The NRC does not directly “accept”
suppliers of safety-related equipment and
services. However, the NRC routinely
performs inspections of nuclear industry
suppliers such as AREVA. The results
of these inspections do not directly
constitute acceptance of a supplier, but
may be used by purchasers of safety-
related equipment and services, as well as
auditing agencies, to support acceptance
or rejection of a supplier for provision of
safety-related equipment and/or services.
The results of NRC inspections may
also be used as the basis for conditional
acceptance of a supplier, depending
on the nature and severity of adverse
inspection results.
6.
What is the extent of international
cooperation in AREVA’s CGD?
Over the years, AREVA has
provided equipment intended for safety-
related applications to many international
customers and, as a result, has worked
to resolve differences between various
regional standards and requirements.
AREVA has been engaged in efforts
in recent years to increase cooperation
among U.S. and international companies
and organizations to harmonize standards.
7.
What are the lessons learnt by
AREVA, which may benefit the program?
AREVA is a learning organization
and utilizes our corrective action program
and lessons learned database to capture
pertinent information and improve based
on our experience. Some of the most
significant lessons learned under the
AREVA Dedication Program are related
to resolution of acceptance discrepancies,
documentation of justification, sourcing
of acceptance criteria and tolerances,
consistency of dedications between
groups, and undeclared digital content.
In terms of resolution of acceptance
discrepancies, a dedication plan is just
that – a plan. As such, there are times
when the results of dedication activities
are not as expected. Per the Electric
Power Research Institute’s (EPRI)
guidance, such unexpected results are
referred to as “discrepancies.” It is
permissible to resolve these discrepant
results through the use of the AREVA
Corrective Action Program. In doing so,
it is very important to provide sufficient
supporting documentation for the
resolution of the discrepant result and to
limit the determination of a discrepancy
to those results that do not in any way alter
the technical evaluation as documented in
the dedication plan. This would include
any changes to the safety function,
failure modes and effects analysis;
critical characteristics; and acceptance
methods. If the resolution of a discrepant
result requires a change to the technical
evaluation, the affected dedication
plan must be revised to complete the
dedication acceptance activities.
The most prevalent finding in
industry audits and NRC inspections
is insufficient documentation for
justification of technical evaluation
requirements and the acceptability of
discrepant inspection and test results. The
AREVA CGD Program establishes the
need for the documentation of a sound
engineering basis to support conclusions
and is reinforced in the review and
approval process with an authorization
program for personnel performing critical
dedication functions.
In terms of sourcing acceptance
criteria and tolerances, a trend in
the
commercial
manufacturing
industry is to refuse to provide
design information for proprietary
reasons. While understandable, it has
resulted in situations where adequate
information from the original equipment
manufacturer is not available for use in
the development of acceptance criteria
with associated tolerances. As a result,
AREVA developed additional means
of establishing acceptance criteria
and determining necessary tolerances
through the use of extensive application
of industry standards and evaluation
techniques such as reverse engineering.
An increase in dedication activities
across multiple groups led AREVA to
institute an authorization program for
personnel who prepare, review and
approve CGD programs to ensure that
those performing their assigned tasks
have the necessary knowledge, obtained
the appropriate level of experience and
are consistent in approaches to complete
dedications.
Undeclared digital content is a
recently identified significant issue that
is currently under evaluation by industry
organizations and within AREVA itself.
For many of our key suppliers, AREVA
has access to design data, which allows
Commercial
Grade...
