DOE G 424.1-1B, Implementation Guide for Use in Addressing Unreviewed Safety Question Requirements
Functional areas: Safety
This Guide, including its attachments, provides information to assist in the implementation of Title 10 Code of Federal Regulations (CFR) Section 830.203, “Unreviewed Safety Question Process,” of the Nuclear Safety Management Rules for Category 1, 2, and 3 nuclear facilities owned or operated by the Department of Energy (DOE), including the National Nuclear Security Administration (NNSA). Cancels DOE G 424.1-1A. Admin Chg 1 dated 4-12-13.
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Superseded By:
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Section 1
AVAILABLE ONLINE AT: INITIATED BY:
www.directives.doe.gov Office of Health, Safety and Security
DOE G 424.1-1B
4-8-2010
IMPLEMENTATION GUIDE FOR USE IN
ADDRESSING UNREVIEWED SAFETY
QUESTION REQUIREMENTS
[This Guide describes suggested nonmandatory approaches for meeting requirements. Guides
are not requirements documents and are not to be construed as requirements in any audit or
appraisal for compliance with the parent Policy, Order, Notice, or Manual.]
U.S. Department of Energy
Office of Health, Safety and Security
Office of Nuclear Safety Policy and Assistance
NOT
MEASUREMENT
SENSITIVE
DOE G 424.1-1B i (and ii)
4-8-2010
FOREWORD
This Department of Energy (DOE) Implementation Guide is available for use by all DOE
components and contractors. Beneficial comments (recommendations, additions, deletions, and
any pertinent data) that may improve this document should be sent to—
James O’Brien
HS-21/GTN
U.S. Department of Energy
Washington, D.C. 20585
Phone (301) 903-1408
Facsimile (301) 903-6172
DOE Guides are part of the DOE Directives System and are issued to provide supplemental
information regarding the Department’s requirements as contained in rules, Orders, Notices, and
regulatory standards. Guides also provide acceptable methods for implementing these
requirements.
This Guide may be used by all contractors for DOE Hazard Category 1, 2, or 3 nuclear facilities,
including contractors for National Nuclear Security Administration (NNSA) Hazard Category 1,
2, or 3 nuclear facilities. Throughout this document, references to a contractor or a DOE
contractor apply to a contractor for NNSA as well.
This Guide was developed in support of Title 10 Code of Federal Regulations (CFR) Part 830,
“Nuclear Safety Management.” It provides guidance for the requirements defined in 10 CFR
830.203, “Unreviewed Safety Question Process.”
This Guide imposes no requirements.
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CONTENTS
FOREWORD.................................................................................................................................. i
1. INTRODUCTION..............................................................................................................1
2. APPLICATION..................................................................................................................2
2.1 Temporary or Permanent Changes in a Facility ......................................................3
2.2 Temporary or Permanent Changes in the Procedures ..............................................4
2.3 Tests or Experiments Not Described in Existing Documented Safety Analyses .....5
2.4 Discovery of Potential Inadequacies in the Existing Safety Analyses ...................5
3. IMPLEMENTATION GUIDANCE .................................................................................6
3.1 Integrated Unreviewed Safety Question Process .....................................................8
3.2 Screening..................................................................................................................8
3.3 Unreviewed Safety Question Determinations ........................................................10
3.4 Documentation and Retention ................................................................................12
3.5 Training and Qualifications ...................................................................................13
ATTACHMENT A. UNREVIEWED SAFETY QUESTION DETERMINATION .......... A-1
Section 2
ATTACHMENT B. UNREVIEWED SAFETY QUESTIONS LESSONS LEARNED ......B-1
ATTACHMENT C. GUIDANCE ON PROCESSING POTENTIAL
INADEQUACIES IN THE EXISTING SAFETY ANALYSES ....... C-1
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1. INTRODUCTION
This Guide, including its attachments, provides information to assist in the
implementation of Title 10 Code of Federal Regulations (CFR) Section 830.203,
“Unreviewed Safety Question Process,” of the Nuclear Safety Management Rules for
Category 1, 2, and 3 nuclear facilities owned or operated by the Department of Energy
(DOE), including the National Nuclear Security Administration (NNSA).
Section 830.203, “Unreviewed Safety Question Process,” allows contractors to make
physical and procedural changes and to conduct tests and experiments without prior
DOE approval if the proposed change can be accommodated within the existing
safety basis. The contractor must evaluate any proposed change to ensure that it will
not affect the safety basis of the facility either explicitly or implicitly. The
unreviewed safety question (USQ) process is primarily applicable to the documented
safety analysis (DSA). The rule references only the DSA, and includes conditions of
approval in safety evaluation reports and facility-specific commitments made in
compliance with DOE rules, Orders, or Policies.
Because application of the USQ process depends on facility-specific information,
results of an unreviewed safety question determination (USQD) in one facility
generally cannot be extrapolated to other facilities. DOE approves procedures to
implement the USQ process as required by 10 CFR 830.203. Where site level and
facility level procedures are used, both site and facility level procedures are approved
by DOE.
Section 830.203 is implemented using contractor procedures for ensuring that proposed
changes to physical characteristics or technical procedures (e.g., operating, test,
surveillance, maintenance, and emergency procedures) are evaluated relative to the
approved safety basis and that those proposed changes determined to involve USQs are
brought to the attention of DOE for review and approval before changes are made.
A proposed change or test involves a USQ if—
the probability of the occurrence or the consequences of an accident or the
malfunction of equipment important to safety previously evaluated in the
documented safety analysis could be increased,
the possibility of an accident or malfunction of a different type than any evaluated
previously in the documented safety analysis could be created, or
a margin of safety could be reduced.
For the purposes of this Guide, equipment important to safety should be understood to
include any equipment whose function, malfunction, or failure can affect safety either
directly or indirectly. This includes safety class and safety significant structures, systems,
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and components (SSCs), and other systems that perform an important defense-in-depth
function, equipment relied on for safe shutdown, and in some cases, process equipment.
Support systems to safety systems that are required for the safety function are also safety
systems, and should be included.
The USQ criteria apply as they affect both workers and the public. In the case of workers,
both those in the immediate proximity of the hazard and collocated workers are included.
Section 3
In accordance with 10 CFR 830.203(g), when a potential inadequacy in the documented
safety analysis is identified; i.e., the DSA may not be bounding or may be otherwise
inadequate, actions must be followed to ensure the safety of the facility. This could be
because of an error in the current safety analysis or because the facility configuration is
not what was analyzed.
The existence of a USQ does not mean that a facility or operation is unsafe. The purpose
of the USQ process is to alert DOE of events, conditions, or actions that affect the DOE-
approved safety basis of the facility or operation and ensure appropriate DOE line
management action. If a change is proposed or a condition is discovered that could
increase the risk of operating a facility beyond that established in the current safety basis,
DOE, including NNSA, line management reviews and determines the acceptability of the
change through the process of approving a revised safety basis that would be developed
and submitted by the contractor.
2. APPLICATION
Title 10 CFR 830.203 applies to all Category 1, 2 and 3 nuclear facilities. The USQ
process applies to all temporary or permanent changes to such nuclear facilities unless a
decision to request DOE approval already has been made, and to potential inadequacies
of safety analyses. Some changes may be such that they can be screened out from a
detailed USQD.
The applicability of 10 CFR 830.203 is broad. Non-safety-related SSCs are not excluded
by the scope of Section 830.203 if they could affect the proper operation of equipment
important to safety that is relied on in the safety basis or create the possibility of an
accident or malfunction of a different type than previously evaluated in the documented
safety analysis. For example, losses of certain non-safety-related systems may represent
critical operational occurrences identified as initiators in the accident analysis. Therefore,
changes to non-safety-related SSCs are evaluated and may be determined to involve a
USQ.
Physical interactions may also fall under the purview of Section 830.203. For example,
the installation of a non-seismically supported piece of equipment above a seismically
qualified component designed to perform a safety function explicitly or implicitly
assumed in the existing safety analyses may constitute a USQ and need to be evaluated.
The following paragraphs define types of changes, tests, and experiments and potential
inadequacies that the USQ process needs to address to comply with Section 830.203.
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These discussions should not be used as bases for screening changes from the USQ
process (or so-called prescreening). Screening should be done in accordance with the
guidance in Sections 3.2, B.9 and B.12.1 of this Guide.
2.1 Temporary or Permanent Changes in a Facility
USQDs should be performed on changes in nuclear facilities as described in the existing
safety analysis text, drawing, or other information that is part of the facility safety basis.
An SSC would be considered changed if any of the following were to be altered: (1) its
function(s), (2) the method of performing those functions, or (3) its design configuration.
Although safety analyses include descriptions of many SSCs, a nuclear facility also
contains many SSCs not explicitly described in the safety analyses. These can be
components, subcomponents of larger components, or even entire systems.
Section 4
Changes to SSCs that are not explicitly discussed in the safety analyses should not be
excluded from the USQ process because changes to these SSCs may have potential to
alter the function of an SSC explicitly described in the safety analysis. Also, a change to
an SSC that does not involve equipment important to safety could initiate an accident or
affect the course of an accident, so virtually no change can be ignored.
It is important to distinguish between changes and routine maintenance activities. Routine
maintenance activities—except those that are not enveloped by current safety analyses or
that might violate a technical safety requirement (TSR)—do not require review under 10
CFR 830.203. A TSR limitation on maintenance activities might require limiting the
number of systems or components that can be taken out of service at one time, or
allowable outage times. Changes to maintenance procedures would constitute changes
that should be reviewed under USQ requirements as discussed in Section 2.2 of this
Guide.
Routine maintenance activities include calibration, refurbishment, replacement with an
equivalent component, and housekeeping. However, some maintenance activities may
constitute changes, such as plant heat exchanger tube plugging where limits are not
specified.
A TSR should specify allowable outage times, permissible mode conditions, and
permitted reduction in redundancy for systems or components removed from service for
maintenance. A USQD need not be performed for these activities.
A USQD should be completed for changes to systems or components that are included in
safety analyses for a nuclear facility and for which allowed outage times are not included
in the TSRs. “Change” as it applies to modes of operation or facility processes is
important when, for example, a facility designed to accommodate several nuclear
processes will modify equipment lineups to accommodate shifting from one process to
another. Changes performed in accordance with approved procedures and considered
within the safety basis of the facility are not considered changes in the facility procedures
for the purposes of 10 CFR 830.203(d) (2).
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Temporary changes such as jumpers and lifted leads, temporary lead shielding on pipes
and equipment, temporary blocks and bypasses, temporary supports, and equipment used
on a temporary basis in a nuclear facility should be evaluated to determine whether a
USQ exists unless such changes are specifically described in existing approved
procedures.
The conservative approach is to provide a written USQD for any change to a nuclear
facility, whether discussed in existing safety analyses or not.
The actual modification implementation process (for example, work authorization
system) used in the field should be reviewed for possible development of USQs. Changes
to plant configuration while work is in progress may involve a USQ relating to facility
operations independent of the safety of the specific work on a modification.
For example, if work involves interrupting a water supply that a fire protection system
depends on, that is not covered by a TSR, that interruption should be examined through
the USQ process. Modifications that are performed in separate, distinct stages (usually
for cost, schedule, or operational considerations) may leave affected SSCs in conditions
not addressed by a USQD that addresses only the final modification configuration but not
the interim times between stages. The work authorization system should include a step to
consider these types of possibilities.
Section 5
2.2 Temporary or Permanent Changes in the Procedures
A USQD may need to be prepared for changes to procedures that are identified in the
facility DSA. However, as discussed in section 3.2 regarding USQ screening, it may not
be necessary for some procedure changes such as non-technical administrative
procedures.
Procedures may be identified explicitly or implicitly in a facility DSA. If the procedure is
implied directly by the nature of a topic in the safety basis (including the operational
safety requirements or TSRs and their bases), that change should be considered to be to a
procedure described in the DSA, so that a USQD is done when appropriate. Such
implicitly described procedures include—
the procedures that implement a safety management program described in the
safety basis,
procedures for implementing a specific administrative control, and
operating, testing, surveillance, and maintenance procedures for equipment when
that equipment is identified in the DSA.
If characteristics of a safety management program described in the safety basis remain
correct, complete, and valid, the result of the USQD would be expected to be negative,
signifying that DOE approval is not needed.
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Procedures are not limited to those specifically identified by type (for example, operating,
chemistry, system, test, surveillance, and emergency planning) but could include
anything described in the DSAs that defines or describes activities or controls over the
conduct of work. Changes to these activities or controls qualify as changes to procedures
as described in the DSA, and therefore need to be evaluated as potential USQs.
Changes to procedures include revisions to existing procedures and developing a new
procedure. For a new procedure that could not have already been described, the question
is, if a DSA were to be prepared (or updated) after the new procedure had been approved,
is the new procedure of a type that would be identified in the DSA. If so a USQD should
be prepared.
2.3 Tests or Experiments Not Described in Existing Documented Safety Analyses
Written USQDs are required for tests or experiments not described in the existing safety
analyses. Tests and experiments should be broadly interpreted to include new activities or
operations. These activities could degrade safety margins during normal operations or
anticipated transients or could degrade the ability of SSCs to prevent accidents or
mitigate accident conditions.
A USQD should be performed to ascertain whether a DOE review and approval of a new
process configuration is needed. For preoperational, surveillance, functional, and startup
tests performed regularly, USQDs are not needed every time a test is performed if the
procedures are not changed. However, one-of-a-kind tests that measure the effectiveness
of new techniques or a new system configuration will need to be evaluated before the
tests can be conducted. Post modification testing should be considered and included in
the USQD for the modification.
2.4 Discovery of Potential Inadequacies in the Existing Safety Analyses
Written USQDs are needed when a contractor identifies or is informed of a situation that
indicates that the safety analyses that support the DOE-approved safety basis may not be
bounding or may be otherwise inadequate.
In general, potential for inadequate safety analysis arises from the following entry
conditions:
a discrepant as-found condition,
an operational event or incident, or
Section 6
new information, including discovery of an error, sometimes from an external
source.
The main consideration is that the analysis does not match the current physical
configuration, or the analysis is inappropriate or contains errors. The analysis might not
match the facility configuration because of a discrepant as-found condition. Analytical
errors might involve using incorrect input values, invalid assumptions, improper models,
6 DOE G 424.1-1B
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or calculation errors. The USQ process starts when facility management has information
that gives reason to believe that there is a potential that the facility DSA might be
inadequate.
Because a safety analysis inadequacy has potential to call into question information on
which authorization of operations is based, per 10 CFR 830.203(g) the contractor is to—
take action, as appropriate, to place or maintain the facility in a safe condition
until an evaluation of the safety of the situation is completed;
notify DOE of the situation;
perform a USQ determination and notify DOE promptly of the results; and
submit the evaluation of the safety of the situation to DOE prior to removing any
operational restrictions that were initiated.
Attachment C provides additional guidance on processing a Potential Inadequacy of the
Safety Analysis (PISA) including guidance on the timing of processing multiple PISAs
found during audits, and the development of Evaluations of the Safety of the Situation
and Justifications for Continued Operation.
The USQ process is not applicable when new requirements are being implemented or
different analysis methods that are used result in changed accident consequences or
probabilities. The USQ process is applicable when the project identifies situations where
it is apparent that the existing safety basis may not be bounding or may be otherwise
inadequate. A reconstitution project should have a process for prompt sorting and
prioritizing of the questions and issues between those that can be addressed as a normal
part of the reconstitution project and those that are to be handled promptly as PISAs. This
process should be sufficiently timely to ensure that the expectations for PISAs can be
met.
The USQ process does not apply to DSA upgrades in response to new requirements or to
the use of new or different analytical tools during the upgrade process. However, the
USQ process does apply when there is reason to believe that the current safety basis may
not be bounding or may be otherwise inadequate.
3. IMPLEMENTATION GUIDANCE
The USQ review process should be integrated into all technical aspects of the contractor
organization responsible for design, engineering, maintenance, inspection, operations,
and assessment of the nuclear facility or activity and individuals involved in these aspects
should be familiar with the requirements of Section 830.203 and should be able to
identify activities that might need to enter the USQ process.
Each facility should identify the methods for making facility changes (for example,
whether changes are made under modification processes, nonconformance processes, or
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maintenance processes). After methods have been identified, the contractor needs to
maintain control of the facility change process and perform and document changes in
accordance with approved procedures. Performing a modification under the guise of
maintenance is not acceptable because the proper control processes to analyze the
proposed change and document its outcome would probably be absent. All reasonable
means for performing a change should be identified because each one provides direct
input into the USQ process and should be integrated accordingly.
Section 7
The USQ process is intended to be implemented along with a change control process that
includes generalized steps for—
identifying and describing the temporary or permanent change,
technical reviews of the change,
management review and approval of the change,
implementation of the change, and
documenting the change.
As part of the technical reviews of a change and separate from the USQ process, the
contractor performs the appropriate type of safety analysis to ascertain whether the
change is indeed safe. The USQ process is used subsequently to determine if final
approval of the change by the contractor is sufficient or if DOE approval must be
obtained.
In performing USQ determinations of a proposed change, documented justification for
the USQ determination should be developed. Consistent with the intent of Section
830.203, this documentation should be complete in the sense that a qualified independent
reviewer could draw the same conclusion.
Contractors should develop procedures that provide detailed guidance for the
performance of the USQ process, including any screening and the USQDs. The
procedures should—
define the purpose;
set forth applicability;
provide definitions of appropriate terms, screening criteria, and the bases for their
application;
include detailed guidance on what is to be considered and evaluated when
performing or reviewing a USQD;
define the qualifications and responsibilities of personnel performing and
reviewing USQDs; and
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require documentation for each USQD.
DOE relies on contractor implementation of the USQ process to preserve the integrity of
the safety basis while allowing flexibility in operations. The contractor responsible for
DOE Hazard Category 1, 2 or 3 nuclear facilities must submit the procedure that defines
its USQ process to DOE for approval as required by 10 CFR 830.203.
3.1 Integrated Unreviewed Safety Question Process
The USQ process should be integrated into the facility’s change control processes. The
change processes should ensure that the USQ process is integrated into existing
procedures or that new procedures are developed as necessary and that the need for
completion of a USQD is not overlooked.
Facility change flow processes for both temporary and permanent changes to SSCs and
documents should be described by a governing policy, procedure, flowchart, or other
description to define clear relationships between the USQ process and other change
control procedures, including design change, configuration control, temporary change,
and procedures governing the preparation, review, and approval of procedures.
Facility procedures should provide that USQ documents (USQDs or screening) are
prepared by one individual and are given independent technical review by a person that
has not been involved in document preparation. That person need not be organizationally
independent.
Facility procedures should provide that facility line management approves action on the
USQ documents. This ensures that line management is informed of the results of the
USQ process and can take whatever follow-up actions are appropriate to enable prompt
submission of changes to DOE for safety review and approval or cancellation of
proposed changes.
Facility operating committee review may be beneficial but should not replace line
management approval. Excessive levels of approvals should be avoided when one
internal approval and a second line management approval is sufficient.
Section 8
3.2 Screening
USQ screening is used to ascertain if it is necessary to expend the valuable time and
resources necessary to perform a USQD, or whether there is reasonable technical
justification for not performing a USQD.
When screening eliminates an item, rationale should be well supported, documented and
retained. Screening should be performed only by personnel qualified to perform USQDs.
Section 830.203 has no specific reference to screening. Conditions for entering the USQ
process are listed in 10 CFR 830.203(d) and discussed in more detail in Sections 2.1
through 2.4 of this Guide. If these conditions are not factors in proposed changes, then
screening out such changes may be appropriate. Screening is intended to be a simple
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go/no-go decision-making step without evaluative consideration. When appropriately
streamlined, a screening decision can often be completed in a matter of minutes.
As discussed in Section 2.1, changes to SSCs not explicitly described in a DSA have the
potential to affect the course of an accident that is addressed in the DSA or create the
possibility of an accident not addressed in the DSA. If evaluating whether an item can be
screened out takes the character of answering the seven USQD questions listed in Section
3.3 the item should not be screened out unless there is a categorical exclusion. If an item
has not been screened out, a USQD should be completed.
Candidate items for screening out include situations wherein the USQ process may not be
applicable as follows:
changes to or the addition of a new TSR;
changes that management has already decided will be submitted to DOE for
safety review and approval (including TSR changes);
installation of an item with an exact replica (same manufacturer, model number,
etc.);1
installation of an item that is on the facility list of “approved equivalent parts,”
which a facility engineer has evaluated and determined that the replacement item
meets all the requirements pertinent to the specific application, including the
service conditions;
changes when common commercial practices would suffice and a formal nuclear-
grade change control process is not warranted (for example, changing fixtures for
fluorescent lighting in a control room); and
changes to documents that are purely editorial and make no technical change.
Another manner in which screening criteria may be applied is through categorical
exclusions. A categorical exclusion is an exclusion from the requirements that USQDs be
performed on proposed changes to a category of SSCs or procedures as a result of a
determination that the category cannot credibly have the capability of creating a USQ if
changed. Documentation of proposed categorical exclusions should be submitted to DOE.
Categorical exclusions are regarded as part of the contractor’s USQ procedure and
require DOE approval.
A categorical exclusion is valid when answers to the seven questions listed in section 3.3
would be “no” for every credible variation within the category. Written justification for
the answers would provide formal documentation of the rationale for the exclusion. The
1 Even for these activities, intermediate configurations which may occur during the activity must be considered
separately under the USQ process. For example, erection of scaffolding in the vicinity of seismically qualified
SSCs to complete these activities should be subject to the USQ process.
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Section 9
screening process should identify and document the categorical exclusion that is
applicable to each proposed change being screened out under this provision.
Screening consideration also is given to the possibility that the matter being considered is
fully covered by a previous USQD (even when location differences are considered). Such
screenings should document the USQD being referenced and explain how the change
being considered is adequately addressed by that USQD.
When considering the resolution of a nonconformance, note that any disposition that
involves a corrective action that does not fully meet all the existing requirements,
including a use-as-is disposition, would constitute a design change; a resolution that
restores the nonconforming SSC to the approved configuration or replacements with
approved equivalent parts does not constitute a change.
See Attachment B, sections B.9 and B.12.1 for additional discussions of screening and
categorical exclusions.
3.3 Unreviewed Safety Question Determinations
Contractors are expected to provide a detailed procedure on how to perform a USQD.
Specific guidance on how to conduct a USQD is in Attachment A. Concepts used to
develop this process are contained throughout this Guide.
Four criteria define a USQ (Section 830.3 of 10 CFR 830). Three can be addressed by
answering seven questions. The fourth PISA criterion also invokes the seven questions as
described later in this section.
Could the proposed change increase the probability of an accident previously
evaluated in the facility’s existing safety analyses?
Could the proposed change increase the consequences (to workers or the public)
of an accident previously evaluated in the facility’s existing safety analyses?
Could the proposed change increase the probability of a malfunction of equipment
important to safety previously described in the facility’s existing safety analyses?
Could the proposed change increase the consequences of a malfunction of
equipment important to safety described in the facility’s existing safety analyses?
Could the proposed change create the possibility of an accident of a different type
than any previously evaluated in the facility’s existing safety analyses?
Could the proposed change create the possibility of a malfunction of equipment
important to safety of a different type than any previously evaluated in the
facility’s existing safety analyses?
Could the proposed change reduce a margin of safety?
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If the answer to any of these questions is yes, the change is considered a USQ.
The term “safety analyses” in these questions refers to those potential events and their
controls considered in the DSA. These include not only the explicit description of the
analyses in the DSA but also any analyses performed to support the summary
descriptions of the analyses in the DSA. When a potential event is discovered that is not
treated in the DSA, it should be considered as a possible new event (see question 5) or as
an indicator of a potentially inadequate safety analysis issue.
For the purposes of this Guide, equipment important to safety should be understood to
include any equipment whose function can affect safety either directly or indirectly. This
includes safety class and safety significant SSCs, including support systems to these
systems that are necessary for the safety function, and other systems that perform an
important defense-in-depth safety function, equipment relied on for safe shutdown, and,
in some cases, process equipment.
Section 10
In the case of a potentially inadequate safety analysis, the fact that there is reason to
believe a safety analysis may be inadequate invokes paragraph 10 CFR 830.203(g),
including performance of a formal USQD. When a potentially inadequate safety analysis
finding arises from an as-found condition, the seven questions can be used in a backward-
looking manner as if the current configuration were a proposed modification. If the
USQD is found to be negative, the contractor could have approved the discrepant
condition without DOE involvement. This would resolve the discrepancy and provide
justification for the current configuration.
The contractor’s USQ procedures should include documenting defensible technical
explanations based on sound engineering judgment for each of the answers to the seven
questions. It is inappropriate to perform extensive analyses or to set a numerical margin
for increases in the probability or consequences within which a positive USQD would not
be triggered.
Such analyses and margins lend themselves to excessive efforts in calculations and abuse
of the intent of the USQ process through manipulations of assumptions and accident
parameters when accident analyses results are highly uncertain, and the possibility that
the results might be a function of the calculation methods used, rather than of safety
differences.
Changes should be evaluated using a method that can determine the direction of
change on frequency or consequence, or on margin of safety by comparing the
situations before-during-and-after the change is made, isolating the effects of the
change, and evaluating and comparing the situation with and without the change and
during implementation.
Except for a PISA based on analytic errors, a discernible direction of change refers to the
effects of the actual change, not to a comparison of the results of a new analysis to the
values cited in the DSA. It is the direction that the change has on probability,
consequences, or margin of safety not the magnitude that is important.
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For example, if the wall thickness of a pressure vessel is going to be increased or the
reaction time of a relay in a safety system is shortened, it is likely that the change is in the
direction of increased safety. If changes are in the opposite direction, safety is likely to be
decreased. Potential increases should be clearly discernible on a qualitative basis. It is
important to recognize that the bounding accidents for workers may be (and probably are)
different from bounding accidents for the public.
If, as a result of a proposed change, additional protective measures (either administrative
or hardware-related) are warranted during a postulated accident situation to ensure
adequate protection of the public or to provide worker safety, the USQD should be found
to be positive on the basis that the change will result in either an increase in probability or
an increase in consequences of an accident absent additional protective measures. A
proposed change should not be defined as including additional protective measures to
reduce exposures such as those related to ALARA (as low as reasonably achievable)
levels and not related to potential accidents. DOE wants to be involved for several
reasons: First, to verify that the degree of protection is adequate; second, to ensure that
the safety basis is properly revised to include the additional protective measures; and
third, to verify that hardware involved is properly classified (for example, as a safety
class or safety significant SSC) and will receive appropriate surveillance and
maintenance.
Section 11
When evaluating “increased potential consequences” of an accident, if the previously
bounding case for that family of accidents is unchanged, then generally there is no
increase in the consequences within the USQ process. It is important that the family of
accidents be related (the same type, fires, for example) and uses the same set of
preventative measures and mitigation. While this is appropriate for public safety,
adequate protection of workers necessitates further evaluation. Each change is evaluated
for increases in the consequences to workers. Further, when considering a new scenario
within a family of accidents, the probability of an accident in that family would be
expected to increase.
The bases of hazard control documents (TSRs or other formats) should identify some
relevant margins of safety. However, all safety basis documents should be reviewed to
identify any relevant margins of safety. See Attachment A, section A.1.7 for a discussion
of margin of safety.
Specific responsibilities of those performing or reviewing USQDs should be clearly
defined. Documentation should also be discussed in the implementing procedures. The
procedures should identify the level of detail necessary to document performance of a
USQD and conclusions reached and include a list of references relied on to reach the
conclusions as well as guidance for the retention of records.
3.4 Documentation and Retention
The contractor needs to retain records of USQ actions taken pursuant to Section 830.203
for at least the full operational lifetime of the facility, including deactivation, long term
surveillance and maintenance, and decommissioning until the facility is categorized as a
DOE G 424.1-1B 13 (and 14)
4-8-2010
below Category 3 nuclear facility. When the contractor operating a facility changes, the
outgoing contractor needs to turn over all USQ records to the incoming contractor. At the
end of each life cycle phase, the contractor should consider retaining the USQ records for
the next phase of the facility life cycle. As a minimum, the facility documentation should
be maintained consistent with DOE Records Schedules.
The contractor maintains the facility DSA and updates it annually. All changes at the
facility should be reflected in these updates at an appropriate level of detail, including
those that were authorized through the USQ process. Previously it was specified that
updates to safety analysis reports (now DSAs) should include all changes implemented 6
months or more before the submittal of the annual update. This has been changed to a
commensurate schedule, to allow flexibility. It may be practical to include more current
changes than prior to 6 months before submittal of the update. However, at least those
implemented 6 months or more before the submittal of the annual update should be
included.
Some contractors have opted for the strategy of updating the DSA continuously through
page changes. Although changes implemented through positive USQDs and DOE
approvals of a request become part of the safety basis as soon as they are implemented,
changes also result from revisions that the contractor implements through negative
USQDs. The continuous page change process can be helpful in ensuring that the DSA
always reflects the current facility configuration.
Section 12
All contractors responsible for nuclear facilities submit to DOE annual summary
descriptions of all USQDs performed. Items that were screened out and a USQD was not
necessary do not need to be included in the annual summary (although they should be
retained in the records of USQ actions). This report should be submitted on a schedule
commensurate with annual update of the DSA.
3.5 Training and Qualifications
Implementing procedures should establish the training and qualifications for personnel
performing the USQ process such as educational background, years and/or types of work
experience and knowledge of the facility, understanding of DOE facility safety basis
requirements (including the USQ process), and familiarity with the facility-specific safety
basis.
All personnel responsible for preparing, reviewing, or approving USQ documents should
receive training on the application of Section 830.203, including any facility-specific
procedures. The recommended interval for retraining is every 2 years.
The contractor should maintain a list of those personnel who are currently qualified to
perform the USQ process.
DOE G 424.1-1B Attachment A
4-8-2010 Page A-1
UNREVIEWED SAFETY QUESTION DETERMINATION
A.1 USQ PROCESS
The unreviewed safety question (USQ) determination is not a substitute for a safety
analysis; it merely serves as a benchmark for whether the safety basis is being preserved.
A safety analysis may show that a proposed change is safe, yet the USQ determination
may find that the change creates a USQ and therefore requires Department of Energy
(DOE) approval prior to implementation. Contractor procedures should clearly establish
the differences between the concepts supporting safety analyses for the documented
safety analysis (DSA) and those used for a USQ determination.
Once it has been determined that a USQ determination is required, it can be approached
by providing an answer to each of the seven questions identified using the USQ
determination process. If any of these questions is answered “yes,” the change is
considered a USQ. An appropriate justification for each answer should be recorded. The
examples given in the following subsections are provided to help the reviewer identify
potential USQs. They are not meant to be examples of USQs. That determination requires
consideration of the DSA for the nuclear facility or other DOE-approved documentation
that provides the safety basis for operations or other activities and the specific details of
the activity.
A.1.1 Could the proposed change 2 increase the probability of an accident previously
evaluated in the facility’s existing safety analyses?
To understand how the probability of an accident occurring could be increased, it is
important to understand how the term “accident” is applied: the term “accident” refers to
the anticipated operational transients and postulated accident scenarios considered in the
DSA.
In answering this question, the first step is to determine the accident scenarios, which
have been evaluated in the previously approved safety analysis that may be affected by
the proposed change. By focusing on the initiators of the previously evaluated accident
scenarios, it can be determined whether there is increased likelihood that a given accident
would occur. The following questions may provide a useful approach in making this
determination.
Section 13
a. Will the proposed change meet the design (including safety functional
requirements as described in the DSA), material, and construction standards
applicable to the structures, systems, and components (SSCs) being modified? If
the answer is “yes,” this aspect of the proposed change might be considered not to
increase the likelihood of the occurrence of an accident, but the aspects of
2 For the purposes of this attachment, “change” will mean any change to procedures or equipment (including prior
undocumented changes), any new tests or experiments, or any new information that has the potential to invalidate
the safety basis.
Attachment A DOE G 424.1-1B
Page A-2 4-8-2010
question b, following, are also considered. If the answer is “no” to any of the
items, either a justification for saying there is no increase in the likelihood of the
occurrence of an accident will need to be developed or it is concluded that the
likelihood of the occurrence of an accident is increased.
b. Could the proposed change affect overall SSC performance in a manner that could
increase the probability of a previously analyzed accident? Possible questions to
ask are—
(1) Could the proposed change use instrumentation with accuracies or
response characteristics that are different from those of existing
instrumentation and could make an accident more likely to occur?
(2) Could the proposed change cause SSCs to be operated outside their design
or testing limits? Examples include the following: overloading electrical
systems, over pressurizing a piping system, or operating a motor outside
its rated voltage and amperage.
(3) Could the proposed change cause system vibration, water hammer,
fatigue, corrosion, thermal cycling, or degradation of the environment for
SSCs that would exceed the design limits?
(4) Could the proposed change cause a change to any SSC interface in a way
that could increase the likelihood of an accident?
A.1.2 Could the proposed change increase the consequences of an accident previously
evaluated in the facility’s existing safety analyses?
In answering this question, the first step is to determine which accidents evaluated in the
safety analyses may have their radiological and hazardous material consequences altered
as a direct result of the change. The next step is to determine whether the change could in
fact increase the consequences of any of the accidents evaluated in the existing safety
analyses. Consequences to workers (in-facility, outside, or collocated) and the public is to
be considered. Examples of questions that assist in this determination are as follows:
a. Could the proposed change degrade or prevent safety functions described or
assumed in the existing safety analyses?
b. Could the proposed change alter any assumptions previously made in evaluating
the radiological and hazardous material consequences in the existing safety
analyses?
c. Could the proposed change play a direct role in mitigating the radiological or
hazardous material consequences assumed in the existing safety analyses?
d. Could the proposed change affect the integrity or function of any fission product
barrier or any radioactive or hazardous material barriers?
DOE G 424.1-1B Attachment A
4-8-2010 Page A-3
A.1.3 Could the proposed change increase the probability of a malfunction of equipment
important to safety previously evaluated in the facility’s existing safety analyses?
Section 14
The safety analyses for the facility assume the proper functioning of equipment important
to safety in demonstrating the adequacy of design. The proper functioning of other
systems, including support systems, is generally assumed. The scope of the USQ
determination should include these other systems. For example, a change that does either
of the following is a change that increases the probability of a malfunction of equipment
important to safety:
degrades the performance of equipment important to safety, assumed to function
in the accident analysis, to below the performance level assumed in the existing
safety analyses; or
increases the challenge to equipment important to safety assumed to function in
the accident analysis (for example, more rapid pressure rise), degrading
performance to a level below that assumed in the existing safety analyses.
In answering this question, the first step is to determine what SSCs could be affected by
the proposed change. Then the effects of this change on equipment important to safety
are evaluated, including both direct and indirect effects. Direct effects are those in which
the change affects the equipment (for example, a motor change on a pump). Indirect
effects are those in which the change affects one piece of equipment, which in turn can
affect equipment important to safety. An example of indirect effects would be one piece
of equipment falling on safety equipment.
After the impact of the change on equipment important to safety is identified, a
determination is made whether an increase in the probability of a malfunction of the
SSCs has occurred. The following are examples of questions that can be used in making
this determination.
a. Will the proposed change meet the original design specifications for materials and
construction practices when the following questions are considered:
(1) Are the seismic specifications met (for example, use of proper supports,
proper lugging at terminals, and isolation of lifted leads)?
(2) Are separation criteria met (for example, minimum distance between
circuits in separate divisions, channels in the same division, and jumpers
run in conduit)?
(3) Are the environmental criteria met (for example, use of materials suitable
for the radiation or thermal environment in which they will be used)?
b. Will the proposed change degrade equipment important to safety reliability by—
(1) imposing additional loads not analyzed in the design?
Attachment A DOE G 424.1-1B
Page A-4 4-8-2010
(2) deleting or reducing system or equipment protection features?
(3) downgrading the support system performance necessary for reliable
operation of the equipment?
(4) reducing system or equipment redundancy or independence?
(5) increasing the frequency of operation of systems/equipment?
(6) imposing increased or more severe testing requirements on systems or
equipment?
If the change adversely affects the equipment important to safety, the likelihood of
equipment malfunction may be increased. A “no” answer to any question in paragraph 3a
or a “yes” answer to any question in paragraph 3b in the immediately preceding examples
may not mean that there is a negative impact on safety. It would indicate, however, the
existence of a USQ and the need for further analyses.
A.1.4 Could the proposed change increase the consequence of a malfunction of equipment
important to safety previously evaluated in the facility’s existing safety analyses?
Section 15
This question asks whether, assuming a malfunction of equipment important to safety, the
change would result in increased hazardous-material or radiological consequences. For
example, consider a change that caused a valve in a safety system to fail in the closed
position where previously it was assumed to fail in the open position. If this change
results in an increase in consequences of an accident, it indicates the change involves a
USQ. In some situations, such as a loss of a preferred failure mode, the change might not
lead to an increase in the calculated consequences but should be considered within the
context of a possible reduction in a margin of safety as discussed in paragraph A.1.7.
A.1.5 Could the proposed change create the possibility of an accident of a different type
than any previously evaluated in the facility’s existing safety analyses?
An accident or malfunction that involves an initiator or failure not considered in the
nuclear facility’s existing safety analyses is potentially an accident or malfunction of a
different type. An example would be turbine missiles from a gas turbine added as an
alternate power source. Certain accidents or malfunctions are not treated in the nuclear
facility’s existing safety analyses because their effects are bounded by similar events with
the same control set that are analyzed.
A seismic-induced failure of a component designed to appropriate seismic criteria will
not cause a malfunction of a different type. However, a change that increases the
probability of an accident previously thought to be beyond extremely unlikely, so that it
is in the credible range, creates a possible accident of a different type.
In answering this question, the first step is to determine the types of accidents evaluated
in the existing safety analyses. The types of credible accidents that the change could
create can then be identified and listed. Evaluating the differences between the two lists
DOE G 424.1-1B Attachment A
4-8-2010 Page A-5
will determine the answer to the question. The accidents evaluated in the existing safety
analyses are generally chosen to be bounding for a broad class of credible accidents.
Thus, comparison of a new accident to the existing analyses may require referral to the
underlying hazard analyses.
A.1.6 Could the proposed change create the possibility of a malfunction of equipment
important to safety of a different type than any previously evaluated in the facility’s
existing safety analyses?
To answer this question, the types of failure modes of equipment important to safety that
have been previously evaluated in the existing safety analyses and that would be affected
by the change are identified. Then the types of failure modes that the change could create
need to be identified. Comparing the two lists can provide an answer to the question. An
example of a change that might create a malfunction of a different type is the relocation
of equipment so that it becomes susceptible to flooding; another example is the
replacement of a mechanical control system with a digital control system that could fail
in a different mode.
A.1.7 Could the proposed change reduce a margin of safety?
This section deals with margins of safety related to DOE-approved hazard control
documents. These controls may be technical safety requirements (TSRs), or they may be
in another form, as permitted in Section 830.205 for certain environmental restoration
activities.
Section 16
For purposes of performing the USQ determination, a margin of safety is defined by the
range between two conditions. The first is the most adverse condition estimated or
calculated in safety analyses to occur from an operational upset or family of related
upsets. The second condition is the worst-case value known to be safe, from an
engineering perspective. This value would be expected to be related to the condition at
which some accident prevention or mitigation action is taken in response to the upset or
accident, not the actual predicted failure point of some component.
Hazard control documents set forth the minimum acceptable limits for operation under
normal and specified failure conditions; they ensure that the available safety equipment
and operating conditions meet the assumptions in the existing safety analyses. They
distill those aspects of the safety analyses that are required to ensure the performance of
safety SSCs and personnel as relied on and defined in the safety analyses.
The bases for a hazard control should define the margin of safety. If the bases of a hazard
control do not specifically identify a margin of safety, the DSA and other appropriate
safety basis documents should be reviewed to determine whether the proposed change,
test or experiment, or new information has or would result in a reduction in a margin of
safety. The judgment on whether the margin is reduced should be based on physical
parameters or conditions that can be observed or calculated.
Attachment A DOE G 424.1-1B
Page A-6 4-8-2010
The safety margin is sometimes implicitly described. A margin of safety can depend on a
parameter other than one of the process variables. Therefore, the precise determination of
a numerical value associated with a change is not always possible. Implicit margins are,
for example, conditions for acceptance for a computer code, method, or industry-accepted
practice. It may be sufficient to determine only the direction of the margin change (that
is, increasing or decreasing) due to the proposed change.
Safety margins generally include worst-case assumptions of initial conditions,
conservative assumptions in computer modeling and codes, allowance for instrument
drift and system response time, redundancy and independence of components in safety
trains, and plant response during operating transient and accident conditions. A change
that affects initial conditions, a system response time, or some other parameter that can
affect the course of an accident analysis supporting the bases of hazard controls is
evaluated to determine whether the change would reduce a margin of safety.
A.2 PERFORMING USQ DETERMINATIONS
In performing USQ determinations of a proposed change, documented justification for
the USQ determination should be developed. Consistent with the intent of Section
830.203, this documentation should be complete in the sense that a qualified independent
reviewer could draw the same conclusion.
The importance of the documentation is emphasized by the fact that experience and
engineering knowledge, rather than models and experimental data, are frequently relied
on to make the USQ determination. Since an important goal of the USQ determination is
to demonstrate that the safety basis is being maintained, the items considered by the
evaluator should be clearly stated.
Documentation of the effects considered will enable the independent reviewers to assess
the adequacy of the USQ determination and its conclusions.
Section 17
DOE G 424.1-1B Attachment B
4-8-2010 Page B-1
UNREVIEWED SAFETY QUESTIONS LESSONS LEARNED
The following list of lessons learned has been developed from experience in applying the
unreviewed safety question (USQ) process.
B.1 TITLE
The title of the process, “unreviewed safety questions,” may suggest that the process
determines the safety of changes. However, the USQ process is intended to determine the
final approval authority for a change [that is, the contractor or Department of Energy
(DOE)].
The USQ process is not intended to replace or to serve instead of a safety analysis of the
change. The safety implications of a change should be reviewed, analyzed, understood,
addressed, determined whether it is acceptable, and documented by the contractor
separately from the USQ process. Using the USQ process instead of the safety analysis
complicates the USQ process. Further, such a usage is inappropriate because the seven
questions to be answered in the USQ determination are not geared toward understanding
whether the change is safe but rather if any of the probability or consequence risk factors
may have increased beyond what has been accepted previously by DOE and hence if the
existing safety controls remain adequate. The change should already be known to be safe
before it enters the USQ process. The USQ process determines if final approval by the
contractor is sufficient or DOE review and approval are required. DOE wants to review
and approve those changes that involve a USQ (that is, when the USQ determination is
positive) to verify that the safety controls are adequate to provide an acceptable level of
safety to the public and workers. The existence of a positive USQ determination does not
mean that the change is unsafe but only that DOE is to be responsible for the final
approval action.
B.2 CONTROL OF HAZARDS DURING INSTALLATION
Hazards that may be involved during the installation of a modification should be
addressed by appropriate safety management programs (such as work planning and
control that includes job hazard analysis or a similar process). As discussed in Section 2.1
of the Guide, the work authorization system should include a step for consideration of
possible USQ situations on the facility safety basis, beyond the planned work.
DOE relies on the contractor’s normal work control procedures to address worker hazards
involved in the actual installation of a modification, not on the USQ process. These
procedures are in programs including radiation protection, hazardous material protection,
work planning and control, Occupational Safety and Health Administration, ALARA (as
low as reasonably achievable), and lockout/tagout. However, the conduct of the work
may involve the introduction of hazards that can constitute a threat to the facility safety
basis such as the use of a crane that could fall on equipment important to safety. So the
USQ process is exercised in considering potential facility safety impacts of modification
work. One basic tenet of the USQ process is to assess the potential change in probability
and consequences risk factors that might be involved when facility operations are
Attachment B DOE G 424.1-1B
Page B-2 4-8-2010
resumed after the modification is implemented. However, sometimes a modification
might be only partially implemented because it is interrupted by unforeseen
circumstances. In such cases, the USQ documentation would need to be revisited to
ensure that it adequately addresses operation with the partially implemented
configuration.
Section 18
B.3 DECLARING A USQ TO EXIST
Section 830.203 assigns the contractor the basic responsibility to evaluate changes and
determine if a USQ exists, or is involved. If the result of the contractor’s USQ
determination is positive, a USQ exists.
DOE can declare that a USQ exists as part of its oversight responsibility of the USQ
process. Such a declaration might result from a disagreement with a contractor’s negative
USQ determination or might result from a condition for which the contractor has not
done a USQ determination. When DOE declares a USQ, it is because DOE believes it
should be involved in the review and approval of the situation to fulfill its
responsibilities.
B.4 SUBMITTALS TO DOE
At some sites, the completed USQ determination form is submitted routinely to DOE for
approval. This practice should be reconsidered because it is not required and can shift the
focus of the DOE review from the safety characteristics of the change to how well the
USQ determination was prepared. For a potentially inadequate safety analysis, the rule
requires that an evaluation of the safety of the situation (not the USQ determination) be
submitted prior to removing any restrictions.
The USQ process does not encompass all situations for which the contractor may need to
request an amendment to the safety basis of a facility. For example, a change to the
hazard categorization level for a facility requires DOE approval, but should not be
addressed by the USQ process. Some contractors have developed a formalized process
for requesting amendments to the safety basis.
At some facilities, the USQ process is being used virtually every time there is need to
request an amendment to the safety basis, regardless of whether or not a change to the
facility or procedures is involved. In some situations, the USQ process is inappropriate. A
formalized procedure that defines the content of the submittal to DOE requesting an
amendment to the facility safety basis could supplement the USQ process (regarding
positive USQ determinations). Such a procedure would also support other situations that
do not involve the USQ process. Such a procedure might outline the expected content as
including items such as (1) an introductory summary of the purpose of the letter and its
contents, (2) a description of the situation that generated the need for action, (3)
alternative actions considered, (4) a description of the selected action, (5) engineering
technical considerations, (6) safety implications of the action, including the results of the
USQ process when applicable, (7) programmatic implications, (8) budgetary
DOE G 424.1-1B Attachment B
4-8-2010 Page B-3
considerations, (9) schedule considerations, and (10) basis on which the contractor
believes that DOE should approve the action.
B.5 NEED FOR USQ DETERMINATIONS FOR TSR CHANGES
Section 830.205 requires that changes to the technical safety requirements (TSRs) be
submitted to DOE for review and approval. Changes to the TSRs could involve the need
either to modify an existing TSR or to add a new TSR. If it is known that a proposed
change only involves a TSR change, it is not required to go through the USQ
determination to determine if DOE approval is also required by 830.203. Similarly, if a
change involves a TSR change, calling the change a positive USQ determination just
because it requires DOE approval would be inappropriate.
Section 19
However, while performing a USQ determination for TSR changes is not required, it may
be desirable. When the TSR change is submitted to DOE for review and approval, the
contractor should include appropriate information to support the contractor's position that
the change should be approved (that is, the contractor should include the basis for the
proposed change). Such supporting information might include some of the same
considerations that would be addressed in a USQ determination.
B.6 TENANT/LANDLORD RELATIONSHIPS
Although not intended as literal, the terms “landlord” and “tenant” are used here to
describe situations where one contractor conducts operations in a facility and has overall
responsibility for a facility safety basis but another contractor also conducts operations in
the facility. In these situations the operations of both the first and the second contractor
must be fully described and analyzed in the facility safety basis in order to comply with
10 CFR 830 Subpart B. However, usually the landlord contractor is fully responsible for
maintaining the integrity of the safety basis. Whether or not a contractual relationship
exists between the contractors, it is important that a practical operational means exist to
ensure disciplined and coordinated implementation of the USQ process for all operations
within the facility.
In these cases, the recommended approach to allow flexibility for the tenant’s activities
and still protect the facility safety basis via the USQ process is to (1) ensure that a
hazards analysis (or other appropriate safety analysis) exists for each tenant activity such
that the collective hazards analyses for all tenant activities are encompassed by the
facility safety basis, (2) procedurally require that the tenant review any changes in its
activities that are being considered against the corresponding hazards analysis, and then
(3) in conjunction with the landlord, perform a USQD against the overall facility safety
basis.
There is a potential conflict between requiring that all changes within a facility be
considered within a formal change control process and allowing researchers and
other tenants’ flexibility to conduct their activities without undue restrictions that
might stifle the desired creativity. The objective should be to impose the formality
necessary to ensure that all activities are conducted safely within the DOE-approved
Attachment B DOE G 424.1-1B
Page B-4 4-8-2010
safety basis for the facility without applying any unnecessary restrictions on the
activities. Having the tenant take an active role in development of an appropriate
activity level safety envelope for the activities within the facility safety basis can
promote ownership. This participation can also enhance safety responsibility without
limiting the activities.
B.7 GRADED APPROACH
During the hazards analysis and safety analysis processes, equipment is classified as
safety class, safety significant, other safety, or non-safety. Once these classifications are
established, they are used to indicate how much effort should be applied. However, no
steps of the USQ process can be eliminated based on such grading.
Section 20
In some situations, attempts to apply the graded approach to the USQ process have
resulted in inadequate USQ determinations. For example, some contractors have applied
the graded approach to the change control processes in a manner that does not require the
application of formal change controls unless the change involves equipment, procedures,
or operations important to safety. Caution needs to be applied in such a situation to
ensure that this approach does not prevent changes from being considered by the USQ
process, which is a subset of change control. The only application of the graded approach
to the USQ process is indirect. The graded approach may give a rough indication of how
much justification or basis information should be provided when explaining the answers
to each of the seven USQ determination criteria. More elaborate and thorough basis
information would be expected for changes to safety equipment than for non-safety
equipment. In any case, the justification for the answers to the USQ determination criteria
needs to be defensible.
B.8 UNIFIED AND CONSOLIDATED PROCEDURES
Contractors should consider the desirability of requiring that each nuclear facility at
the site adhere to a single sitewide USQ procedure and sitewide USQ
training/qualification requirements. Facility-specific considerations, such as
identifying the safety basis documents, could be addressed by appendices to the
sitewide procedure. At some sites, each nuclear facility uses a different USQ
procedure, leading to inconsistencies and misapplications. One DOE field office
assessment found that a root cause of USQ problems was the lack of a common
procedure and common USQ training. A single sitewide USQ procedure could
improve the quality of the USQ process by taking advantage of the best aspects of
each of the different facility procedures. Using the same USQ forms for screens and
USQ determinations and using the same training and qualification requirements can
help develop a high-quality USQ process across the site.
B.9 USQ SCREENING
USQ screening is intended to be a simple go/no-go decision-making step, without
evaluative consideration. When appropriately streamlined, this step in the USQ process
can often be completed in a matter of minutes. Screening to determine whether an SSC is
DOE G 424.1-1B Attachment B
4-8-2010 Page B-5
described in the safety analyses (safety basis) should consider only whether the
equipment is identified anywhere in the safety basis. Screening criteria should not be
based on whether the SSC is formally classified as a safety SSC (that is safety class or
safety significant), is taken credit for in the safety analysis (or accident analysis) chapter
of the safety basis document, nor whether the particular characteristic(s) of the SSC to be
changed are taken credit for.
The basic intent of screening is to eliminate unnecessary time and effort being spent
performing a USQ determination if there is no possible way that the change could impact
the safety basis and involve a USQ. Conversely, screening criteria make certain that
changes which could possibly involve a USQ are “screened in” and hence a USQ
determination is performed. The USQ screening criteria center on the question of whether
the item to be changed is described in the safety basis.
Section 21
An example of an inappropriate, highly evaluative, screening criterion is: “Does this
change significantly adversely impact the ability of an SSC described in the safety basis
to perform its safety functions?” Such a criterion encompasses four separate
considerations: (1) determining if the SSC is identified in the safety basis, (2) finding out
what the safety functions are for the SSC, which might not be stated very clearly or
completely, (3) evaluating if the impact of this change could adversely affect the
capability to perform a safety function, and (4) evaluating if the impact could be
significant. All but the first consideration are evaluative considerations that depend
strongly on which individual does the USQ screen. These types of evaluative
considerations should be in the domain of the USQ determination, not part of the simple
screening step.
If someone were to subdivide the safety basis documents into those parts that are
“descriptive” and those parts that are important to safety, the results would be highly
subjective. Limiting the performance of USQ determinations to only those SSCs taken
credit for in the safety analysis chapter, or even further to only those characteristics of
SSCs taken credit for can lead to serious problems, including bypassing the USQ
determination and thereby, unknowingly exceeding the bounds of the safety basis.
Similarly, limiting screening to safety SSCs (that is, those identified as safety class or
safety significant) before a USQ determination is done is inappropriate due to the
potential for unrecognized direct or indirect interactions.
B.10 DOE INVOLVEMENT IN THE USQ DETERMINATION
The contractor should make every effort to complete its USQ determinations without
DOE involvement. DOE has charged the contractor with performing the USQ process to
determine if contractor approval is sufficient. At times, there will be borderline cases or
“gray areas” where engineering judgment will play a large role in the determination. The
contractor should complete the determination with sufficient justification to defend the
conclusion, despite whether the final determination is positive or negative.
Attachment B DOE G 424.1-1B
Page B-6 4-8-2010
B.11 USQS AND CRITICALITY SAFETY EVALUATIONS
All proposed new or changed processes involving criticality safety that necessitate a new
or revised Criticality Safety Evaluation, including those in an experimental facility,
undergo a USQ review by the Nuclear Safety Management rule. When the USQ
determination is positive indicating the need for DOE review and approval of the change,
the safety analyses and controls associated with the approved action become part of the
safety basis for the facility. Any changes necessary to the DSA and TSR documents
because of the change should be incorporated at the next annual update. The results of the
USQ determination define the need for DOE approvals of the supporting criticality safety
evaluations and explicit updates of the DSA and TSRs.
B.12 EFCOG ISSUES
Representatives of DOE and Energy Facilities Contractor Operating Group (EFCOG) met
to discuss issues and request clarifications on several USQ implementation issues that
had arisen since 10 CFR 830 Subpart B had been made effective. This section provides
guidance relating to the more significant of these issues.
B.12.1 Screening
Section 22
It has been argued that the definition of a USQ in 10 CFR 830.3 and the conditions for
entering the USQ process in 10CFR830.203(d), which refer to the existing documented
safety analysis, allow screening out of proposed changes to a facility if the change does
not involve anything in the existing safety analysis. For example, the definition of a USQ
includes the situation where “the probability or the consequences of an accident or the
malfunction of equipment important to safety previously evaluated in the documented
safety analysis could be increased.” Also, for example, the USQ process must be entered
in situations where there is a “temporary or permanent change in the facility as described
in the existing documented safety analysis.” This has been described as the “as versus is”
controversy. That is, it is argued that the arbiter of a USQ situation is the existing
documented safety analysis, rather than the potential for increased risks, whether or not
described in the DSA.
The argument for exclusion of some changes from the USQ process by screening out,
because the involved systems or components are not described in the existing DSA
presumes that the existing DSA is complete in all respects with regard to descriptions,
hazard identification, and controls. While the quality and completeness of safety basis
documents is increasing, there is still a wide disparity in those attributes of approved
safety bases throughout the DOE complex. It is inappropriate to screen out a change that
involves systems or hazards that are not described in the existing safety analysis. There
are several reasons why this is so. The change itself could constitute a new test or
experiment. Introduction of a new hazard could cause a new type of accident or
malfunction, or increase the likelihood of an accident or malfunction. Any of these could
result in a USQ, so a USQ determination is needed.
DOE G 424.1-1B Attachment B
4-8-2010 Page B-7
The allowance of a limited amount of time for management-level evaluation of possible
safety issues relating to discovery, or new information, prior to invoking the PISA
provisions of the USQ requirements is appropriate to the screening process. That is, a
limited amount of technical judgment relative to a safety nexus can be exercised.
However, when such considerations take the nature of answering the seven USQ criteria
questions, the item should not be screened out. Instead, a USQD should be completed.
Further, if the screening process involves examination of whether or not the issue is dealt
with in the DSA, the process should include consideration, as described above, of
whether another entry into the USQ process (PISA, test or experiment not described in
the DSA, or the possibility of an accident or failure of a different type) should be
invoked.
B.12.2 Nonconforming SSCs
Clarification was requested for the proper handling of situations where it is found that an
SSC does not conform with the documented design description and specifications
(discrepant as-found state), under the USQ requirements.
If the corrective action is to bring the item into conformance (see discussion in
section 3.2), then it may be reportable under ORPS requirements, but it would not require
a USQD. However, if the resolution would be another approach (e.g., use-as-is, or
alternatively, replace with another unapproved component), then the provisions of
10 CFR 830.203(d) (temporary or permanent change in the facility as described in the
existing documented safety analysis) must be invoked. Formally, this would invoke PISA
provisions, for which the ORPS report would constitute notification of DOE. Prior action
of assuring a safe condition upon discovery should already have been taken. So, if the
decision is to “use-as-is,” for example, the next step would be to perform a formal
USQD.
Section 23
Whatever the case, it would be prudent to investigate to see if there had been a valid
safety reason for the non conforming condition that had not been properly reflected in a
change to the DSA.
B.12.3 Discernable Increase (in Frequency or Consequence)
The answer to what is a discernable increase is in the rationale provided in the USQD
first four of seven questions. The rule (see 10 CFR 830.3 USQ definition) does not permit
a numerical margin before which an increase constitutes a USQ. The rationales for the
USQ answers should be convincing to an independent reviewer that the change could
result (or not result) in an increase. Site-specific quantitative guidance that allows for a
numerical margin is implicitly acknowledging that they have a USQ, when that margin is
used to dismiss the question.
A rationale against having such margins (independent of the fact that they are not
compliant with the rule) is that with them a contractor could make many changes that
individually would not violate the margins, but taken together over years could result in a
Attachment B DOE G 424.1-1B
Page B-8 4-8-2010
massive increase in operational risk that DOE did not consciously accept and which
never got documented in the safety basis.
Further, it would seem that if a contractor were to go to the extent of quantifying an
increase in consequences or frequency, the contractor would have done all that would be
required to prepare a USQD, and more. Therefore the contractor is not saving anything
(and is likely expending more than appropriate) by invoking a margin.
B.12.4 DOE Approval of Revisions to a USQ Procedure
The 10 CFR 830 rule requires that the USQ procedure be reviewed and approved by
DOE. This Guide does not address approval of revisions except in the context of changes
of procedures.
B.12.5 Major Modifications
The possibility exists that a major modification to a facility could be broken down
into a series of changes that, individually, would not be considered major. Avoidance
of a USQ issue by breaking a modification down into many “minor modifications”
could be considered an intentional failure to implement 10 CFR 830 requirements in
good faith.
10 CFR 830.3 defines a major modification as one that “substantially changes the
existing safety basis for the facility.” This includes the content of the safety basis, not just
consideration of bounding accidents. Guidance on when a proposed change to a facility is
a major modification (requiring a preliminary documented safety analysis) versus a
change provided in DOE Standard 1189, Integrating Safety into the Design Process
B.12.6 Transportation Activities under 10 CFR 830.203 USQ Requirements
Transportation activities are regulated under 10 CFR 830, except for those activities
regulated by the Department of Transportation. This guidance can be applied directly to
transportation activities.
Non-routine transfers (see TSD Chapter IX) must all undergo the USQ process.
Proposed changes in transportation activities that do not lead to using packaging in
conditions that may lead to exceeding its performance envelope should not result in a
positive USQD, in most cases.
Changes that potentially expose transfers to new hazards or increased likelihood of
accidents would be expected to result in positive USQDs.
B.13 OPERABILITY DETERMINATIONS
It is necessary to determine the proper handling of situations expeditiously under the
USQ requirements where it is found that an SSC does not conform to the safety
Section 24
DOE G 424.1-1B Attachment B
4-8-2010 Page B-9
basis description and requirements (discrepant as-found state). The SSC may be degraded
such that there is a loss of quality or functional capability or a nonconforming condition
may exist with the SSC or its documentation.
When a degraded or nonconforming SSC is identified as a PISA, the contractor must first
“take action, as appropriate, to place or maintain the facility in a safe condition” (10 CFR
830.203(g)(1)). A safe condition may include continued facility operation if, although a
degraded or nonconforming SSC is not fully qualified, the impact on safe facility
operations is judged to be acceptable, possibly aided by operational restrictions and the
TSRs are still being met in terms of required operable equipment for the given MODE of
operations and associated ACTIONS. If a SSC identified in a TSR is determined to be
inoperable, then in accordance with the facility TSR, the action statement(s) in the TSR
must be implemented. The TSR action statement may direct the facility operator to go to
a MODE in which the piece of equipment is not required or the facility operator may
choose to take this action even though the TSRs do not explicitly direct it.
There may be situations where an SSC has been degraded such that there is a loss of
quality or functional capability or a nonconforming condition may exist with the SSC or
its documentation but the SSC has not been determined to be inoperable. These situations
may constitute a PISA. When a degraded or nonconforming SSC is identified as a PISA,
the contractor must first “take action, as appropriate, to place or maintain the facility in a
safe condition” (10 CFR 830.203(g) (1)). A safe condition may include continued facility
operation if, although a degraded or nonconforming SSC is not fully qualified, the impact
on safe facility operations is judged to be acceptable, possibly aided by operational
restrictions and the TSRs are still being met in terms of required operable equipment for
the given MODE of operations.
An operability determination is a forward-looking evaluation by the operating contractor
of whether there is a reasonable expectation that continued operation of the facility is safe
even when a degraded or nonconforming condition exists. An immediate operability
determination should be made based on the best available information and operational
restrictions imposed, if necessary, upon confirmation of the condition. Subsequently, a
final determination should be made and documented following a thorough engineering
evaluation. The elements of the final operability determination should include
description of the degraded or nonconforming condition of the SSC
description of the relationships on safe operations of the SSC functions
evaluation of the operability of the SSC given its condition—
o using analysis, tests, operating experience, and/or engineering judgment
o considering availability of other equipment, conservatisms and margins, and
cumulative effects of other outstanding degraded or nonconforming conditions
Attachment B DOE G 424.1-1B
Page B-10 4-8-2010
specification of additional operating restrictions if necessary (e.g., compensatory
measures, additional engineering analysis by a certain date)
specification of restoration actions (may be added later).
Section 25
Restoration actions for the degraded or nonconforming condition are to be developed by
the contractor and scheduled at the first available opportunity commensurate with the
safety significance and extent of restoration actions in an integrated manner with other
facility commitments and resources. The final operability determination may be included
as part of the evaluation of the safety of the situation required to be submitted to DOE
before removal of any operational restrictions.
DOE G 424.1-1B Attachment C
4-8-2010 Page C-1
GUIDANCE ON PROCESSING
POTENTIAL INADEQUACIES IN THE EXISTING SAFETY ANALYSES
C.1 INTRODUCTION
This attachment provides guidance on the performance of each of the four steps required
per 10 CFR 830.203(g) upon discovery of a Potentially Inadequate Safety Analysis
(PISA). In addition, this attachment discusses an acceptable method for evaluating new
information to determine whether a PISA exists, and discusses the use of Justifications
for Continued Operation (JCO). This attachment also discusses situations involving
multiple PISAs. Figure 1 provides a schematic of the PISA process.
C.2 PROCESSING INFORMATION TO DETERMINE WHETHER A PISA EXISTS
10 CFR 830. 203(g) requires certain actions for a PISA. A PISA may result from
situations that indicate that the safety basis may not be bounding or may be otherwise
inadequate; for example, discrepant as-found conditions, operational events, or the
discovery of new information. It is appropriate to allow a short period of time (hours or
days but not weeks) to investigate the conditions to confirm that a safety analysis is
potentially inadequate before declaring a PISA. The main consideration is that the safety
analysis does not match the current physical configuration, or the safety analysis is
inappropriate or contains errors. If it is immediately clear that a PISA exists, then the
PISA should be declared immediately.
DOE Sites should consider including this initial confirmatory process as part of their
USQ procedures.
C.3 PLACING OR MAINTAINING THE FACILITY IN A SAFE CONDITION
Upon identification of a PISA, 10 CFR 830.203(g) requires the contractor to place or
maintain the facility in a safe condition. The determination of what constitutes a safe
condition is the responsibility of the contractor. The contractor should take conservative
action to impose operational restrictions to ensure the facility is safe. Operational
restrictions may include restrictions on work activities for the affected part of the facility,
imposition of additional controls (e.g., fire watches if the adequacy of a fire protection
control is in question), or placing the facility into a different TSR mode. In addition, per
10 CFR 830, Subpart B, Appendix A, Section G (3), the contractor must evaluate the
operability of impacted safety systems and components and enter any applicable TSR
action statements.
Further, the rationale (for the determination that the facility is in a safe condition) should
be documented. This should not involve an extensive/detailed analysis as the evaluation
of the safety of situation will occur at a later stage of processing the PISA, e.g., after the
USQ determination.
Attachment C DOE G 424.1-1B
Page C-2 4-8-2010
C.4 EXPEDITIOUSLY NOTIFYING DOE WHEN THE INFORMATION IS
DISCOVERED
Section 26
After the potentially inadequate safety analysis has been confirmed, 10 CFR 830.203(g)
requires contractors to take four specific actions. One of those actions is to notify DOE of
the situation. The current DOE reporting system (DOE O 231.1A and the associated
Manual, DOE M 231.1-2) requires that a potential inadequacy of the safety basis be
reported as a Significance Category 3 situation. The Occurrence Reporting and Processing
System (ORPS) may be used for this notification if the report explicitly states that the
situation involves a “potential USQ involving a potentially inadequate safety analysis.”
The ORPS reporting designation used for this notification is Group 3 B (2), “Declaration
of a potential inadequacy of the documented safety analysis.” The DOE Facility
Representative and/or other DOE management responsible for the facility should be
notified immediately. The DOE notification should clearly identify any operational
restrictions that were invoked to ensure the facility is in a safe condition. No DOE
approval of the operational restrictions is needed; however, DOE should review them and
can direct other restrictions be implemented if needed.
C.5 PERFORMING A USQD AND NOTIFYING DOE OF THE RESULTS
Another action required for a potentially inadequate safety analysis is the preparation of a
USQ determination for the situation. This should be performed in a short period of time
(hours or days, not weeks) following confirmation of the PISA. In the event that the USQ
determination is positive, the DOE reporting Manual (DOE M 231.1-2) requires that this
condition be categorized and reported as a Significance Category 2 under ORPS Group 3
B (1), “Determination of a positive Unreviewed Safety Question (USQ) that reveals a
currently existing inadequacy in the documented safety analysis.” The contractor must
notify DOE of the results of whether the USQD was positive or negative. Examples of
notification methods may include: updating the ORPS report or submitting a separate letter
to DOE. As part of performing the USQD, new information may arise that results in the
contractor identifying additional operational restrictions that should be imposed and
modifying its operability determination. No DOE approval of any new operational
restrictions is needed; however, DOE should review them and can direct other restrictions
be implemented if needed.
C.6 COMPLETING AN EVALUATION OF THE SAFETY OF THE SITUATION (ESS)
C.6.1 Processing of Evaluation of the Safety of the Situation
10 CFR 830.203(g) requires contractors to submit an ESS to DOE “prior to removing any
operational restrictions.” The contractor should develop an ESS following completion of
the PISA USQD, since input from the USQD analysis is useful in developing the ESS3.
3 10 CFR 830.203(g) lists 4 actions that contractors must perform when a PISA is discovered. Although nothing in
10 CFR 830.203(g) requires these actions be performed in order, it is logical and recommended that they be
performed in this manner.
DOE G 424.1-1B Attachment C
4-8-2010 Page C-3
Section 27
The timing of the ESS is a function of whether the USQD is positive or negative. The
ESS associated with positive USQDs should be developed within a short period of time
following completion of the USQD (as soon as practicable and should not take more than
a month) taking into account the safety risk presented by the situation and the
effectiveness of operational restrictions imposed. However, if the facility is placed in a
TSR safe MODE (i.e., a MODE where the PISA condition no longer represents a hazard),
there is no specific time limit for submittal of the ESS in this situation. Also, there is no
specific time limit for submittal of an ESS for a negative PISA USQD because the
condition of the facility is such that DOE approval would not have been needed (per the
USQ requirements) if the facility was intentionally put in this condition. However, in
accordance with 10 CFR 830.203(g), the ESS must be submitted prior to lifting any
operational restrictions. Further, it is a good practice to address the cause of the PISA
(e.g., correct discrepant conditions and/or update safety basis) and return the facility to
normal operations (i.e., lift operational restrictions) as soon as practicable. No DOE
approval of the ESS is needed for the negative PISA USQD.
The ESS should be reviewed by DOE to determine whether the facility (with any
remaining operational restrictions in place) is in a safe condition. Furthermore, DOE
should formally approve ESSs for PISAs that result in a positive USQD. DOE review of
the ESS should focus on the adequacy of the contractor’s analysis of the impact of the
PISA on the safety of the facility and the capability of the operational
restrictions/controls to mitigate the hazards and to compensate for any potential decreases
in the facility safety caused by the PISA. The approval authority for the DOE should be
at the same level as the Safety Basis Approval Authority level for the facility.
In situations of a positive USQD and if operations are to continue for an extended period
of time (i.e., greater than a month) under the restricted conditions of other than a TSR
safe MODE, then the contractor should evaluate whether further (more detailed) analysis
may be appropriate to justify that continuance. This may take the form of a Justification
for Continued Operation (JCO) (see Section C.7). Alternatively, it is appropriate for the
contractor to update the ESS to include a more detailed analysis utilizing the outline
described in Section C.6.2 taking into consideration the JCO content described in Section
C.7 and to submit the updated ESS to DOE.
As needed, the contractor should incorporate changes to resolve the USQ into the next
annual DSA/TSR update if not submitted earlier or as may be specified in the JCO.
C.6.2 Content of Evaluation of the Safety of the Situation
If the PISA USQD is negative, the ESS should document the assessment of the safety of
the situation, and provide evidence that the immediate controls placed on the facility or
activity to ensure a safe condition are not required and can be removed. If the PISA
USQD is positive, the ESS should document the assessment of the safety of the situation,
and provides the basis for how the actions taken (including implementation of operational
restrictions), and/or planned actions, ensure safety.
Attachment C DOE G 424.1-1B
Page C-4 4-8-2010
Section 28
If a DSA modification is made as part of the resolution of the PISA or the Justification
for Continued Operation, then in accordance with 10 CFR 830.207, a Safety Evaluation
Report (SER) is needed. If not done earlier, then any needed changes to the safety basis
should be made at the next annual update.
The following is a recommended format and content for an ESS:
Title
Description of occurrence or discovery and any immediate compensatory actions
taken (i.e., operational restrictions). Date PISA was discovered and ORPS report
number.
Results of immediate safety assessment (including discussion of probability and
consequence risk factors) and of USQD (positive/negative). Reference relevant
documents.
Results of any subsequent safety analysis developed to further support
conclusions as to safety of the facility with and/or without operational
restrictions/compensatory measures.
Path forward. Discuss if additional work is to be performed to resolve the issue,
and anticipated completion date.
Additional appropriate content for an ESS in the case of a positive USQD could include:
Current operational status of the facility.
Clear identification of all operational restrictions needed to maintain the facility in
a safe condition.
Analysis that addresses the safety impact of the PISA with the operational
restrictions removed (or with the operational restrictions in place if their removal
is not proposed).
Path forward for restoring the facility into compliance with the DSA (e.g., by
revising the DSA or by correcting the discrepant condition).
Summary of recommendations and conclusions.
The safety analysis should be bounding and the level of detail sufficient to provide
confidence that the facility is being maintained in a safe condition.
C.7 JUSTIFICATION FOR CONTINUED OPERATION (JCO)
A JCO is a mechanism by which a contractor may request that DOE review and approve
a temporary change to the facility safety basis that would allow the facility to continue
operating in view of a specific and unexpected situation, considering the safety
DOE G 424.1-1B Attachment C
4-8-2010 Page C-5
significance of the situation and any compensatory measures being applied during this
period. A JCO is associated only with situations where the PISA USQD is positive.
However, as discussed in Section C.6.1, it is also appropriate to update the ESS in lieu of
developing a JCO.
If the PISA arises from the situation where analytical errors in the DSA are identified or
the analysis is otherwise inappropriate, a proposed DSA change should be prepared and
submitted to DOE. However, if the DSA change cannot be submitted in a timely manner
(e.g., within a month) and a strong programmatic need exists to continue operations, a
JCO that defines specific operational restrictions or other compensatory measures that
will be maintained should be submitted to DOE for approval. A PISA could also arise
from a discrepant as-found condition (e.g., installed equipment not meeting design
specifications). In this case, the facility should be restored to meet the design conditions.
However, there may arise situations where it may not be possible to align the facility
configuration with the safety analysis in a timely manner (e.g., a month), and there may
be a need to continue operations. In this situation, a JCO that defines specific operational
restrictions or other compensatory measures that will be maintained should be submitted
to DOE for approval.
Section 29
The JCO should analyze the hazards and identify controls, appropriate for the hazards
associated with the PISA and the length of time the conditions which resulted in the PISA
are expected to exist. This analysis should be consistent with the approach in 10 CFR 830
Subpart B, Appendix A, for developing a documented safety analysis. Given that a JCO
is intended to address emergent conditions in a timely manner; the associated analysis
and controls/compensatory measures can be more simplified and conservative/bounding
than in a final DSA. By taking a more bounding approach, control effectiveness can be
assured even though the analysis may not be as complete as would be in a final DSA.
When DOE approves such a JCO, the JCO and any DOE imposed conditions of approval
become temporary additions to the safety basis that would permit operations to continue
under the conditions specified, including a defined termination point. DOE review of the
JCO should follow a similar approach to approval review of the DSA and should be
documented in a SER (e.g. using a graded approach consistent with DOE-STD-1104
(Review and Approval of Nuclear Facility Safety Basis and Safety Design Basis
Documents). The approval authority for the DOE should be at the same level as the
Safety Basis Approval Authority level for the facility.
A JCO is expected to define an appropriate set of temporary hazard controls (that is,
compensatory measures) to be in effect during the life of the JCO. In some cases, these
hazard controls might involve temporary changes to the facility TSRs. If the JCO results
in additional or modified controls, a review of the planned changes should be done prior
to implementation to ensure the changes properly address the JCO. A JCO cannot change
a TSR in the non-conservative direction but may alter it into a more conservative
direction. Additional analysis could be performed later, in order to justify the relaxation
of any identified controls.
Attachment C DOE G 424.1-1B
Page C-6 4-8-2010
A JCO should have a predefined, limited life as necessary to perform the safety analysis
of the unexpected situation, to identify and implement corrective actions, and to update
the safety basis documents on a permanent basis. The JCO should define the termination
point of the life of the JCO. In most cases, this would take the form of a functional point,
such as the completion of turnover of a physical modification for routine operations,
which would occur after implementing the modification, post-modification testing,
updating critical documentation, and training of the operations staff. The contractor
should take actions to resolve the conditions that require the JCO or modify the safety
basis during the next annual update to make the JCO no longer necessary. JCOs should
not continue past a required annual DSA update unless the JCO was submitted within
three months of the submittal date of the annual update. In some rare cases, it may not be
practical to achieve this goal of being within three months of the submittal date of the
annual update. It is recommended that those changes be handled as soon as practicable. If
this cannot be accomplished, the contractor should formally notify DOE of the reasons.
Section 30
A JCO is not an appropriate means to request a change of the safety basis for a planned
operation, a new experiment, a major modification, or new construction. In these cases, a
request for a change to the facility safety basis should be prepared by the contractor and
submitted to DOE for approval. Because the JCO is established in response to an
unexpected condition, event, or new information, it is inappropriate to use it in planning
new activities. A JCO should not used in place of an exemption to 10 CFR 830
requirements.
The JCO should be maintained as provided for in 10 CFR 830.202(c) for safety basis
maintenance until the conditions that resulted in the PISA have been corrected and the
JCO has been terminated.
The following is a recommended format and content for the JCO.
Title
Executive Summary (Optional, depending on length of document)
Purpose of the Document (JCO): For example, to provide the rationale for the
safety of operations while the PISA exists. May also include a brief discussion on
how the JCO was developed in accordance with site processes for meeting 10
CFR 830 safety basis requirements.
Discussion of Background (What condition(s) led to need for JCO. Note: could
cite the ESS which transmits the JCO, or precedes it, as this material is in the
ESS). Include a discussion on the PISA, facility status, and the steps taken
(including any operational restrictions put in place) to ensure the facility was in a
safe condition. Also, discuss results of the USQ determination.
Description of what operations are authorized to occur during the time the PISA
exists (given the compensatory measures are in place) along with rationale for
why the operations need to continue.
DOE G 424.1-1B Attachment C
4-8-2010 Page C-7
Compensatory Measures (Risk-reduction activities being applied immediately).
Provide a detailed discussion of any established controls or existing or planned
compensatory measures. Include a discussion of how the measures will be
implemented.
Safety Assessment. Briefly discuss the results of the USQ determination and the
impact on mitigated consequence and event frequency with any compensatory
measures in place, and whether these risk factors are time dependent. This may be
a qualitative assessment of the relative risk of operating the facility with the PISA
and any compensatory measures in place as compared to operating the facility as
analyzed in the DSA.
Planned Corrective Actions (Actions that will be developed as the permanent
solution). Include a discussion of actions to take place to resolve the PISA and to
ensure that the facility can be safety operated in accordance with the approved
safety basis. The JCO should include a summary of recommendations and
conclusions, including the specific proposed path or action to terminate the JCO
(e.g., DSA change, restoring the facility configuration to the analysis).
Termination of JCO (Those events/date that will define termination of JCO).
Discuss the expected date or events (e.g., correction of deficiency) at which time
the JCO will be terminated and the actions/approvals that will be necessary to
terminate the JCO.
C.8 Situations Involving Multiple PISAs
Section 31
A special case regarding PISAs exists when dealing with external audit team multiple
concerns, each of which may (or may not) indicate the possibility of a potential
inadequacy in the safety analyses. It may be impractical for facility staff to assess the
situation quickly and disposition multiple concerns in the time frame normally expected
for deciding whether a concern indicates a PISA (hours to days) and performing a USQD
for each finding that qualifies as a PISA. In the face of multiple issues, it might be
concluded that the short-term response to assuring a safe condition is to shut down
operations. This might not be appropriate in all cases.
As an option in these cases, except where it is apparent that an imminent hazard exists,
DOE should be consulted without delay, and a mutually agreed upon approach to
handling the concerns, including an expeditious schedule, should be developed. This
approach should have a high priority for addressing the concerns, should prioritize the
safety related concerns, and should disposition each as described for individual PISAs.
Where it is apparent that an imminent hazard exists, the four steps for a potential
inadequacy should be undertaken without delay.
A similar situation exists for design basis reconstitution projects where documentation on
the original design bases may be lost or outdated. In this case, it can be expected that a
team of engineers may identify many questions or issues that may not have current
documentation and which may or may not constitute PISAs. For the purposes of the USQ
Attachment C DOE G 424.1-1B
Page C-8 4-8-2010
process, design reconstitution projects can be regarded as DSA upgrades. For DSA
upgrades, USQs should not result from the use of new analytical tools or in response to
new requirements. A reconstitution project should have a process for prompt sorting and
prioritizing of questions and issues between those that should be addressed as a normal
part of the reconstitution project and those that should be handled promptly as PISAs.
This process should be sufficiently timely to ensure that the expectations for PISAs can
be met.
D
O
E
G
424.1-1B
A
ttachm
ent C
4-8-2010
P
age C
-9 (and C
-10)
D
O
E
G
424.1-1B
A
ttachm
ent C
4-8-2010
P
age C
-11 (and C
-12)