ML16196A237
| ML16196A237 | |
| Person / Time | |
|---|---|
| Issue date: | 12/26/2017 |
| From: | Andrea Kock Division of Materials Safety, Security, State, and Tribal Programs |
| To: | |
| Goldberg P | |
| References | |
| RIS-05-031, Rev. 1 | |
| Download: ML16196A237 (31) | |
See also: RIS 2005-31
Text
UNITED STATES
NUCLEAR REGULATORY COMMISSION
OFFICE OF NUCLEAR MATERIAL SAFETY AND SAFEGUARDS
WASHINGTON, DC 20555-0001
December 26, 2017
NRC REGULATORY ISSUE SUMMARY 2005-31, REVISION 1
CONTROL OF SECURITY-RELATED SENSITIVE UNCLASSIFIED NONSAFEGUARDS
INFORMATION HANDLED BY INDIVIDUALS, FIRMS, AND ENTITIES SUBJECT TO NRC
REGULATION OF THE USE OF SOURCE, BYPRODUCT,
ADDRESSEES
All radiation control program directors and State liaison officers.
All licensees, certificate holders, applicants, and other entities (hereafter referred to as
licensees and others) subject to regulation by the U.S. Nuclear Regulatory Commission (NRC)
for the use of source, byproduct, and special nuclear material, excluding the following:
- All holders of and applicants for an operating license or construction permit under
Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Domestic Licensing of
Production and Utilization Facilities, and those licensees that have permanently ceased
operations and have submitted certifications under 10 CFR 50.82(a)(1) or have
submitted applications for license termination under 10 CFR 50.82(b)(1).
- All holders of and applicants for a power reactor early site permit, combined license,
standard design approval, or manufacturing license under 10 CFR Part 52, Licenses,
Certifications, and Approvals for Nuclear Power Plants. All applicants for a standard
design certification, including such applicants after initial issuance of a design
certification rule.
- All holders of and applicants for certificates for reactor designs.
INTENT
The NRC is issuing this regulatory issue summary (RIS) to accomplish the following:
- Inform licensees and others of the screening criteria that the NRC uses to identify and
protect security-related sensitive information in documents generated by the NRC and in
documents developed by licensees and others, particularly those received by the NRC.
(Enclosure 2)
- Encourage licensees and others to identify security-related sensitive information in
documents submitted to the NRC by using the marking procedures in Enclosure 1 and the
screening criteria in Enclosure 2.
RIS 2005-31, Rev. 1
Page 2 of 6
- Encourage licensees and others that may possess security-related sensitive information
to control the information in order to limit the risk that the information might fall into the
hands of those who would use it for malevolent acts.
No specific action or written response is required.
BACKGROUND INFORMATION
The NRC traditionally has given the public access to a significant amount of information about
the facilities and materials the agency regulates. Openness has been and remains a
cornerstone of the NRCs regulatory philosophy. The Atomic Energy Act of 1954, as amended;
subsequent legislation; and various NRC regulations have given the public the right to
participate in the licensing and oversight process for NRC licensees. To participate in a
meaningful way, the public must have access to information about the design and operation of
regulated facilities and use of nuclear materials. However, the NRC and other Government
agencies have always withheld some information from public disclosure for reasons of security,
personal privacy, or designation as proprietary information (commercial or trade secret
protection).
In the post-September 11, 2001, environment, the NRC has found it necessary to be more
judicious in determining what information to voluntarily release so that it does not inadvertently
provide assistance to those who might use certain information for malevolent acts. The NRC
has issued orders, advisories, and rules; taken specific actions on the security of its licensed
facilities; and assessed and revised its policies and practices for making information available to
the public. As one such action, the NRC temporarily suspended public access to documents in
its electronic Agencywide Documents Access and Management System (ADAMS) on
October 25, 2004. Subsequently, the NRC screened those documents to determine whether
they contained security-related sensitive information. Based on this screening, the NRC
returned a large number of documents to public access in ADAMS. This screening process
continues as requests for specific documents are received and as new documents are created
by the NRC and received from licensees and other entities.
The NRC has continued to presumptively withhold some categories of documents from routine
public release. In SECY-04-0191, Withholding Sensitive Unclassified Information Concerning
Nuclear Power Reactors from Public Disclosure, dated October 19, 2004 (ADAMS Accession
No. ML043140175), and SECY-05-0101, Withholding from Public Disclosure Sensitive
Unclassified Information Concerning Materials Licensees and Certification Holders, dated
October 7, 2005, (ADAMS Accession No. ML051040407) (non-public) the staff proposed to
withhold certain information on fire protection and emergency planning and response to ensure
that information that could reasonably be expected to be useful to a potential adversary was not
made public. The Commission approved the initial withholding of this information and the
review of the information for release in response to requests such as those made under the
Freedom of Information Act (FOIA). See Staff Requirements Memorandum SECY-04-0191
dated Nov. 9, 2004 and Staff Requirements Memorandum SECY-05-0101 dated October 7,
2005. In SECY-15-0032, Reviewing Documents for Public Release Using Sensitive
Unclassified Non-Safeguards Information Guidance, dated March 6, 2015 (ADAMS Accession
No. ML14352A172), the staff proposed to discontinue this policy and instead apply the NRCs
sensitive unclassified nonsafeguards information (SUNSI) policy to review, release, and
withhold fire protection and emergency preparedness documents. The Commission approved
this proposal in its staff requirements memorandum to SECY-15-0032, dated June 15, 2015
(ADAMS Accession No. ML15167A090). The advice in this RIS reflects that change.
RIS 2005-31, Rev. 1
Page 3 of 6
To facilitate the screening process for the public release of information, the NRC developed
screening criteria and issued two RISs that pertain to nuclear reactors for conducting its
reviews. On November 7, 2005, the NRC issued RIS 2005-26, Control of Sensitive
Unclassified Nonsafeguards Information Related to Nuclear Power Reactors, (ADAMS
Accession No. ML051430228) for assessing whether documents associated with reactor
licensees should be made publicly available. On December 23, 2015, the NRC issued
RIS 2015-17, Review and Submission of Updates to Final Safety Analysis Reports, Emergency
Preparedness Documents, and Fire Protection Documents, (ADAMS Accession No.
ML15321A400) to remind licensees of the review and submission requirements of
10 CFR 2.390, Public Inspections, Exemptions, Requests for Withholding, on information that
may be withheld from public disclosure.
As part of related efforts in the nonreactor arena, the NRC has developed the enclosed criteria
for identifying security-related sensitive information that the staff encourages licensees to
screen out or to mark and protect as sensitive information, particularly before those licensees
that handle source, byproduct, or special nuclear material submit documents to the NRC.
The advice in this RIS and its enclosures does not apply to classified information, Safeguards
Information, or Safeguards InformationModified Handling, which by law must be withheld from
the public.
SUMMARY OF ISSUE
SUNSI includes information that, if lost, misused, or modified, can reasonably be foreseen to
harm the public interest, the commercial or financial interests of an entity, the conduct of NRC
and Federal programs, or the personal privacy of individuals. It also includes security-related
information. If practical, licensees and others that submit documents to the NRC should avoid
including any security-related sensitive information to permit the release of the document to the
public in its entirety. However, if that is not practical, the following steps will help ensure that
sensitive information is not released:
(1) Screening of Licensee-Generated Documents
To ensure that any security-related sensitive information in submitted documents is not
made publicly available in ADAMS, the NRC is encouraging licensees and other entities
to screen submittals in accordance with the criteria in Enclosure 2. In addition, to ensure
that licensees and other entities identify and control security-related sensitive information
in their documents, the NRC is encouraging them to develop implementing procedures
to screen documents that might have sensitive security-related information in order to
identify and control the information appropriately. The goal is to limit the risk that the
information might fall into the hands of those who would use it for malevolent acts.
(2) Cover Letter
If a cover letter that does not itself contain sensitive information is used to transmit a
document(s) that contains security-related sensitive information, the cover letter should
clearly state this. Furthermore, the cover letter should have a statement that indicates
that once its sensitive attachments are removed, the cover letter itself may be handled
as an uncontrolled document. However, if the cover letter itself contains security-related
sensitive information, it cannot be decontrolled.
RIS 2005-31, Rev. 1
Page 4 of 6
(3) Marking Documents That Contain Security-Related Sensitive Information
As shown in Section A of Enclosure 1, include the marking Security-Related
InformationWithhold under 10 CFR 2.390 at the top center of every page.
If submitting both a public and a nonpublic version of the same document, licensees and
other entities should black out the sensitive information in the public version or withhold
the sensitive information with a notation that it was withheld on the basis that it is
security-related information.
Alternately, security-related sensitive information may be segregated from the main
body of the document and included only in attachments to the submittal. In this
scenario, only the attachments that contain security-related sensitive information would
be marked for withholding from public disclosure. If this approach is used, the public
version does not need to be marked as containing security-related sensitive information.
Enclosure 1, Section B, contains additional information on suggested handling and
methods of submitting security-related sensitive information.
Protection of Security-Related Sensitive Information
Documents that contain security-related sensitive information should be protected from public
disclosure using methods similar to those for protecting proprietary information. To the extent
practical, any existing documents that contain security-related sensitive information that
licensees or other entities have previously made available to the public should be withdrawn
from public access. Licensees and other entities should have sufficient internal controls to
prevent release of information to limit the risk that sensitive security-related information could be
released to someone with malevolent intent. In addition to the points enumerated above, other
methods to prevent the inadvertent release of security-related sensitive information include
(1) restricting access to electronic recordkeeping systems that contain such information,
(2) controlling the reproduction, distribution, and destruction of potentially sensitive records, and
(3) releasing sensitive information only to those individuals who have a need to know the
information to perform their jobs and who are made aware of the security-related nature of the
information.
Certain categories of security-related sensitive information under 10 CFR Part 37, Physical
Protection of Category 1 and Category 2 Quantities of Radioactive Material, must be protected
pursuant to 10 CFR 37.43(d) and 37.77(f), as described in more detail in Section D, Security
Program Information, of Appendix 3, Reviews of Medical, Industrial, and Academic Users of
Nuclear Materials, to Enclosure 2.
Much of the NRCs information is readily available to the public through the NRCs Web site
(http://www.nrc.gov) and ADAMS (http://www.nrc.gov/reading-rm/adams.html). In addition, the
agency may release other information to the public in response to formal or informal requests.
Although the NRC developed these security-related sensitive information screening criteria with
the principles of FOIA in mind, a review for security-related sensitive information does not
substitute for a FOIA review. The NRC will continue to review and process FOIA requests
under 10 CFR 2.390(d)(1), independently from the security-related sensitive information review
process.
RIS 2005-31, Rev. 1
Page 5 of 6
BACKFIT DISCUSSION
This RIS informs addressees of the screening criteria that the NRC uses to identify and protect
security-sensitive information, and to encourage licensees and others to identify and control
such information. This RIS requires no action or written response beyond that already required
by NRC regulations, and is, therefore, not a backfit under the backfitting provisions of
10 CFR 70.76, 72.62, or 76.76, all titled Backfitting. Consequently, the NRC staff did not
perform a backfit analysis.
FEDERAL REGISTER NOTIFICATION
A notice of opportunity for public comment was not published in the Federal Register because
this RIS is informational and does not represent a departure from current regulatory
requirements and practice.
CONGRESSIONAL REVIEW ACT
This RIS is not a rule for purposes for purposes of the Congressional Review Act, 5 U.S.C. §§
801-808.
PAPERWORK REDUCTION ACT STATEMENT
This RIS does not request any information collections and, therefore, is not subject to the
Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.).
RIS 2005-31, Rev. 1
Page 6 of 6
CONTACTS
Please direct any questions about this matter to the technical contacts listed below.
/RA Kevin Williams for/
Andrea L. Kock, Acting Director
Division of Material Safety, State, Tribal
and Rulemaking Programs
Office of Nuclear Material Safety
and Safeguards
Technical Contacts: Paul Goldberg, NMSS/MSTR Raynard Wharton, NMSS/DSFM
301-415-7842 301-415-7497
E-mail: Paul.Goldberg@nrc.gov E-mail: Raynard.Wharton@nrc.gov
Kevin Ramsey, NMSS/FCSE Zahira Cruz, NMSS/DUWP
301-415-7506 301-415-3808
E-mail: Kevin.Ramsey@nrc.gov E-mail: Zahira.Cruz@nrc.gov
301-287-9076
E-mail: Gary.Langlie@nrc.gov
Enclosures:
1. Suggested Markings and Handling
for Those Subject to NRC Regulation
2. Screening Criteria for Security-Related
Sensitive Unclassified Nonsafeguards
Information
Note: NRC generic communications may be found on the NRC public Web site,
http://www.nrc.gov, under NRC Library/Document Collections.
RIS 2005-31, Rev. 1
Page 6 of 6
SUBJECT: CONTROL OF SECURITY-RELATED SENSITIVE UNCLASSIFIED NON-
SAFEGUARDS INFORMATION HANDLED BY INDIVIDUALS, FIRMS, AND
ENTITIES SUBJECT TO NRC REGULATION OF THE USE OF SOURCE,
BYPRODUCT, AND SPECIAL NUCLEAR MATERIAL
DATE: December 26, 2017
ML16196A237 CAC A34010
OFC NMSS/MSTR NMSS/MSTR NMSS/MSTR OGC OGC NMSS/FCSE NMSS/DSFM/
Staff
NAME PGoldberg SAtack AMcIntosh ACoggins CSafford KRamsey RWharton
DATE 12/15/16 12/5/16 7/15/16 9/12/17 9/18/2017 1/24/17 2/14/17
OFC NMSS/DUWP OE OCIO OCIO OIP NMSS/FSCE NMSS/DUWP
NAME ZCruz DFurst Via e-mail RGagnon PHabighorst CErlanger JTappert
DCullison
DATE 1/26/17 1/23/17 9/18/17 6/30/16 2/09/17 2/13/17 1/26/17
OFC NMSS/DSFM NSIR/DSO QTE NMSS/MSTR
NAME MLayton MBailey CHsu KWilliams for
AKock
DATE 2/14/17 1/27/17 2/22/17 12/26/17
OFFICIAL RECORD COPY
RIS 2005-31, Rev. 1
Enclosure 1
Page 1 of 2
SUGGESTED MARKINGS AND HANDLING FOR THOSE SUBJECT TO NRC REGULATION
This enclosure provides information on markings suggested by the U.S. Nuclear Regulatory
Commission (NRC) for pages of a document that contains security-related sensitive
information (Section A) and suggested handling of such documents (Section B).
Section A: Page Markings
Place the overall page marking on the top
and bottom of all pages of a document that
contains security-related sensitive
information.
Security-Related Information Note that a cover letter must include the
Withhold under 10 CFR 2.390 marking if the letter or any attachment to
the letter contains security-related
information. If the cover letter itself is
nonsensitive, add the following statement
to the bottom of the letter: Documents
transmitted herewith contain sensitive,
unclassified information. When
separated from the sensitive information,
this document is decontrolled.
Ensure that the subject line is
nonsensitive.
Security-Related Information
Withhold under 10 CFR 2.390
RIS 2005-31, Rev. 1
Enclosure 1
Page 2 of 2
Section B: Appropriate Controls for Handling Documents
Access: Access is based on need to know to perform official licensee,
applicant, or other entity functions.
Storage: Documents can be stored openly within licensee, applicant, or
other entity facilities but with electronic or other access controls
(e.g., key cards, guards, alarms).
Mail: Documents should be sent through U.S. Postal Service first class
mail, registered mail, express mail, or certified mail in a single
opaque envelope with no external markings to indicate contents
covered by Title 10 of the Code of Federal Regulations
(10 CFR) 2.390, Public Inspections, Exemptions, Requests for
Withholding.
Electronic Transmission: Information can be handled over the telephone if the recipient is
confirmed as being authorized to access the information, over
facsimile if it is confirmed that a recipient who is authorized to
access the information will be present to receive the transmission,
or over encrypted computer e-mail (using computer software such
as SecureZip).
Note that the NRC uses SecureZip to encrypt electronic
information before transmitting security-related sensitive
information by e-mail to licensees and other entities. Users will be
prompted for a password to access a free download of the reader.
RIS 2005-31, Rev. 1
Enclosure 2
Page 1 of 23
SCREENING CRITERIA FOR SECURITY-RELATED SENSITIVE
U N CLASSIFIED NONSAFEGUARDS INFORMATION
December 26, 2017
INTRODUCTION
This enclosure provides the criteria that should be used to determine what information may be
disclosed to the public and what information should be withheld to prevent inadvertent
assistance to those who might wish to use security-related information for malevolent acts. As a
reminder, the advice in this enclosure applies to all security-related information except for
classified information, Safeguards Information, or Safeguards Information - Modified Handling.
BACKGROUND
Historically, the U.S. Nuclear Regulatory Commission (NRC) has made large amounts of
information, more than required by law, routinely available to the public. However, in the
post-September 11, 2001, environment, the NRC, like many other agencies, has found it
necessary to be more judicious in what it voluntarily releases so that it does not inadvertently
provide assistance to those who might use this information for malevolent acts.
The NRC developed guidance in SECY-04-0191, Withholding Sensitive Unclassified
Information Concerning Nuclear Power Reactors from Public Disclosure, dated
October 19, 2004, and advised licensees in NRC Regulatory Issue Summary (RIS) 2005-26,
Control of Sensitive Unclassified Non-Safeguards Information Related to Nuclear Power
Reactors, dated November 7, 2005, on the conduct of a broad security/sensitivity review to
assess whether documents associated with reactor licensees should be made publicly available
in the first instance as a matter of administrative discretion. The NRC has now developed the
guidance in this enclosure, which addresses the criteria for screening from public disclosure
certain types of information associated with various classes of materials licensees, applicants,
certificate holders, and other entities.
Consistent with the Commissions Staff Requirements Guidance on SECY 05-0091, Task
Force Report on Public Disclosure of Security-Related Information, dated June 30, 2005, the
screening criteria in these guidelines ...should follow the principles for withholding
security-related information under FOIA. Although the NRC developed these security-related
sensitive information screening criteria with the principles of the Freedom of Information Act
(FOIA) in mind, a review for security-related sensitive information does not substitute for a FOIA
review. The NRC will continue to review and process FOIA requests independently from the
security-related sensitive information review process.
RIS 2005-31, Rev. 1
Page 2 of 23
ORGANIZATION OF THIS ENCLOSURE
Table 1 outlines the contents of this enclosure:
- Section 1 indicates the criteria under which documents may be released to the public
without any further screening. However, Section 1 also notes specific requirements for
withholding documents in certain cases even if the documents meet the criteria.
- Section 2 contains general criteria for screening documents that do not meet the criteria
in Section 1.
- Appendices 1-5 contain guidance, in addition to that in Section 2, for screening
documents specific to fuel cycle facilities; decommissioning and low-level waste sites;
medical, industrial, and academic uses of nuclear materials; spent fuel/transportation;
and export/import, respectively.
Table 1 Stakeholders Using This Guidance and Applicable Sections of the Guidance1
STAKEHOLDER APPLICABLE SECTION AND APPENDIX
Fuel cycle facilities, including milling, Sections 1 and 2 for general information and
conversion, enrichment, and fuel fabrication Appendix 1
facilities
Decommissioning and low-level waste sites Sections 1 and 2 for general information and
Appendix 2
Medical, industrial, and academic uses of Sections 1 and 2 for general information and
nuclear materials Appendix 3
10 CFR Part 71 certificate holders and Sections 1 and 2 for general information and
registered users Appendix 4, Parts A, B, and E
Special attention should be given to the
guidance on detailed design drawings and
control of the registered users list for
transportation packages.
1 With regard to high-level waste, Subpart J, Procedures Applicable to Proceedings for the Issuance of Licenses
for the Receipt of High-Level Radioactive Waste at a Geologic Repository, of Title 10 of the Code of Federal
Regulations (10 CFR) Part 2, Agency Rules of Practice and Procedure, contains requirements that an applicant
of the proposed geological repository at Yucca Mountain in Nevada must follow when making information publicly
available through the Licensing Support Network.
RIS 2005-31, Rev. 1
Page 3 of 23
.
STAKEHOLDER APPLICABLE SECTION AND APPENDIX
10 CFR Part 71 quality assurance program Sections 1 and 2 for general information and
(QA) holders Appendix 4, Parts A, B, and E
Based on the NRC staffs experience, most QA
program holder submittals do not contain
sensitive information as defined in this RIS.
However, attention should be given to the
guidance on detailed design drawings and
control of the registered users list for
transportation packages.
10 CFR Part 72 certificate holders, general Sections 1 and 2 for general information and
licensees, and specific licensees Appendix 4, Parts A, B, C, D, and E
Export and Import Sections 1 and 2 for general information and
Appendix 5
RIS 2005-31, Rev. 1
Page 4 of 23
.
SECTION 1: GENERAL SCREENING CRITERIA FOR DOCUMENTS TO BE RELEASED TO THE
PUBLIC
A. Low-Hazard Information Documents
Documents that meet the following criteria may be released without the need for any
further screening, except as specifically noted:
(1) Documents that specify the quantities of radionuclides located in any single
location if those quantities are below the International Atomic Energy Agencys
Category 3 quantities (as listed in Table 2 of these guidelines). However, the
staff will withhold from public access the exact location of the material even if
material levels are below the Category 3 threshold values. Thus, the staff will
release a document if it indicates a general location (e.g., in a certain building),
but if the document gives the exact location (e.g., Room 12), the staff will redact
the exact location unless the location is intuitively obvious.
(2) Documents from licensees (other than fuel cycle licensees) authorized to
possess radionuclides that are not listed in Table 2. However, the staff will
withhold information on the exact location of this radioactive material.
(3) Uranium recovery documents describing or discussing yellow cake and mill
tailings only.
(4) Current information on decommissioning materials sites with diffuse
contamination only. However, check for other active licenses or radioactive
material at the site (e.g., high-activity reactor components and high-activity
waste) and screen any related documents separately.
(5) Documents concerning terminated licenses for which all radioactivity except
diffuse contamination has been removed. However, screen old files for
operational information that may contain sensitive information.
B. Information Readily Available to the Public Elsewhere (Based on Reactor Criteria
Approved by the Commission (SECY-04-0191))
The following criteria apply to information on materials facilities:
(1) If the information is available from open source literature such as text books,
Web sites, or other sources, an NRC decision to withhold the information may
decrease the openness of the agencys regulatory programs without obstructing
an adversary.
(2) Information clearly visible from locations accessible to the public, including
general (low-resolution) drawings of the site and adjacent areas, is generally
released.
RIS 2005-31, Rev. 1
Page 5 of 23
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SECTION 2: GENERAL SCREENING CRITERIA FOR DOCUMENTS TO BE WITHHELD
FROM PUBLIC RELEASE
This section lists the general screening criteria that the NRC staff will use for withholding
information from the public, as well as the information that the staff will release.
A. Facilities Where Licensed Material May Be Located
(1) The NRC staff will withhold the following information related to locations and
quantities of radioactive material that equal or exceed the threshold values listed
in Table 2:
(a) information for identifying the exact locations of radioactive material
The staff will release a document if it indicates a general location (e.g., in
a certain building), but if the document gives the exact location
(e.g., Room 12), the staff will withhold it unless the location is intuitively
obvious.
(b) information on possession limits or actual inventories of radionuclides
(c) manufacturers and model numbers of sealed sources and devices
(d) for fuel cycle facilities, information on possession limits and
inventories of enriched uranium and plutonium exceeding a critical mass
(e) lists of licensees registered to use transportation packages approved by
the NRC under 10 CFR Part 71, Packaging and Transportation of
Radioactive Material
(2) The NRC staff will release the following information:
(a) identification of radionuclides and form
(b) 10 CFR Part 71 certificates and information under 10 CFR Part 72,
Licensing Requirements for the Independent Storage of Spent Nuclear
Fuel and High-Level Radioactive Waste, and Reactor-Related Greater
Than Class C Waste, related to radionuclide form, content, quantities,
model numbers, and locations of independent spent fuel storage
installations regardless of the quantities
(c) event reports involving lost, stolen, abandoned, or found radioactive
material, regardless of whether the radioactive material equals or exceeds
the quantities specified in Table 2
B. Design of Structures/Equipment
(1) The NRC staff will withhold the following information for design of structures and
equipment (site specific):
RIS 2005-31, Rev. 1
Page 6 of 23
.
(a) information related to security requirements, information from analyses
that could reveal vulnerabilities, reports of specific or predicted failures,
and any other information that could reasonably be expected to be
useful to potential adversaries
(b) information related to predicted structural failures that could be useful to
potential adversaries (see Appendix 1 for specific guidance on fuel cycle
facilities)
(2) The NRC staff will release the following information:
Notwithstanding paragraph B(1)(b) above, the NRC staff will release information
on the design of structures provided to the NRC, which typically consists of
analyses to show that the design feature will withstand the combinations of
forces associated with design-basis events and natural hazards. Such analyses
do not typically provide realistic information on the failure of structural features
and, except for fuel cycle facilities, are not considered sensitive.
C. Nearby Facilities
The NRC staff will withhold information related to nearby facilities if the information
might reasonably be helpful to those planning a malevolent act.
D. Design Information: Spent Fuel Casks, Transportation Packages, and Other Information
(1) The NRC staff will withhold information related to nonsite-specific spent fuel
casks, transportation packages, sealed source and device catalog and files, and
other such items, including the following types of information:
(a) drawings that show detailed design information
(b) design/performance information that indicates vulnerabilities that could
reasonably be expected to be useful to potential adversaries
(2) The NRC staff will release text information describing how spent fuel casks,
transportation packages and devices/sources are constructed.
E. Emergency Planning/Fire Protection Information
(1) In regard to emergency planning/fire protection information, the NRC staff will
withhold the following information:
(a) the document in its entirety if it contains site-specific information that
would be useful to an adversary in planning a malevolent act
The NRC staff will review any considerations or requests for release on a
case-by-case basis. As part of the review, the staff will determine
whether the State or local governments are withholding related
information as sensitive.
RIS 2005-31, Rev. 1
Page 7 of 23
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(b) detailed information describing response capabilities (e.g., personnel and
resources available)
(c) information and drawings identifying the locations of radioactive material
and onsite routes and pathways to or from the locations of radioactive
material, especially detailed descriptions of areas not normally visible to
the public
(d) information that State or local government agencies have designated as
sensitive
F. Security Program Information
Much information related to security programs at fuel cycle facilities and other materials
facilities with high risk sources has already been designated to be withheld as classified
information, Safeguards Information, or proprietary information. In addition to
withholding classified information, Safeguards Information, or proprietary information,
the NRC staff will withhold any security information that could reasonably be expected
to be useful to potential adversaries. In addition, certain categories of information are
protected under 10 CFR Part 37, Physical Protection of Category 1 and Category 2
Quantities of Radioactive Material.
G. Vulnerability and Security Assessments, Accident Analyses, Safety Analyses, and Risk
Assessments
(1) The NRC staff will withhold the following information:
(a) assessments that use a malevolent event as an initial condition
(e.g., vulnerability/security analysis)
(b) descriptions of structural features related to potential malevolent acts
(c) detailed information and drawings describing the specific locations of
equipment that is relied upon for safety or security
(d) discussions of safety features or mitigation strategies within
vulnerability/security assessments
(e) any analysis that identifies which events have significant consequences
and which events do not
(f) information related to security events and any information that could be
useful to an adversary as a result of the identification of vulnerabilities
(2) The NRC staff will release typical accident analyses that involve conservative
models to demonstrate a facilitys ability to respond to design-basis events
(i.e., nonsecurity-related events), unless the analysis could reasonably be
expected to be useful to an adversary.
RIS 2005-31, Rev. 1
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APPENDICES 1-5: ADDITIONAL GUIDANCE FOR SECURITY-RELATED SENSITIVE
INFORMATION SCREENING REVIEWS
Appendices 1-5 contain additional guidance for screening documents for security-related
sensitive information specific to types of facilities and uses of materials. These appendices
cover the following topics, respectively:
(1) fuel cycle facilities, including milling, conversion, enrichment, and fuel fabrication
facilities
(2) decommissioning and low-level waste sites
(3) medical, industrial, and academic uses of nuclear materials
(4) spent fuel/transportation (10 CFR Part 71 certificate holders and registered users;
10 CFR Part 71 QA program holders; and 10 CFR Part 72 certificate holders, general
licensees, and site-specific licensees)
(5) export/import licensing
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APPENDIX 1
FUEL CYCLE FACILITY REVIEWS
NRC Contact: Division of Fuel Cycle Safety, Safeguards, and Environmental Review, Office of
Nuclear Material Safety and Safeguards
A. Descriptions of Facilities Where Licensed Material May Be Located
(1) Withhold information on the quantity of enriched uranium or plutonium authorized
in possession limits, or possessed in actual inventories, when the quantity
exceeds a critical mass. Information identifying radionuclides and
chemical/physical forms authorized may be released.
(2) Withhold information related to military contract operations, even if it is publicly
available elsewhere.
(3) Withhold information that identifies the exact locations (e.g., detailed floor plans)
of radioactive and hazardous material whose release or theft could allow
adversaries to create a diversion for theft of material or result in a significant
consequence. Planning a sabotage activity (e.g., bombing a building) would
likely require less detailed information than planning a theft, for which exact
locations would likely be necessary.
(4) Withhold information about the design of structures that consists of analyses to
show that design features will withstand the forces associated with both
security-related scenarios and nonsecurity-related scenarios, such as tornadoes,
high winds, and snow loads. Analyses indicating forces associated with
nonsecurity regulatory requirements could be useful in planning terrorist
activities. For example, information related to seismic loadings could be used to
determine blast loads for bombs.
(5) Withhold detailed design information, including diagrams showing dimensions,
material properties, and descriptions of how the facility/equipment is constructed.
Additionally, withhold process information that could potentially allow an
adversary to access radioactive or hazardous materials or gain knowledge of
detailed information or potential weaknesses of systems designed to ensure safe
operations (necessary to prevent or mitigate accidents) at fuel cycle facilities.
B. Nonsite-Specific Design Information
There is no additional fuel cycle facility guidance for this category.
C. Emergency Planning/Fire Protection Information
(1) Withhold site-specific information that would be useful to an adversary planning a
malevolent act. This includes detailed information or potential weaknesses of
systems designed to ensure safe operations (necessary to prevent or mitigate
accidents) at fuel cycle facilities. Withhold detailed information and drawings of
areas not normally visible to the public. This includes information identifying
routes to or from the locations of radioactive and hazardous material whose
release or theft could allow adversaries to achieve their goals.
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(2) Withhold information that State or local government agencies have designated as
sensitive.
(3) Withhold any detailed accident analysis that identifies which accidents have
significant consequences and which accidents do not. Accident analysis
information can appear in many documents (e.g., an emergency plan, fire
protection plan, integrated safety analysis summary, environmental report or
assessment). General information may be releasable, but details should be
withheld.
(4) Withhold site-specific emergency action levels used to declare emergencies.
(5) Withhold detailed information about response capabilities (e.g., personnel and
resources available).
D. Security Program Information
(1) Much information related to security programs at fuel cycle facilities and other
materials facilities with high-risk sources has already been designated to be
withheld as proprietary information, classified information, or Safeguards
Information.
(2) Withhold information on security equipment and programs, descriptions of
equipment and radioactive or hazardous materials, and accident studies that
closely resemble programs, equipment, radioactive or hazardous materials, and
studies at other active licensee sites if that information would reveal
vulnerabilities or would be expected to be useful to adversaries at active licensee
sites.
E. Vulnerability and Security Assessments and Accident Analyses
(1) Withhold detailed information and drawings describing the exact locations of
radioactive or hazardous materials or that would allow adversaries to gain
knowledge of detailed information or potential weaknesses of systems designed
to ensure safe operations (necessary to prevent or mitigate accidents) at fuel
cycle facilities.
(2) Withhold any detailed accident analysis that contains accident sequences,
identifies accident consequences, identifies systems and components that are
relied upon for safety, or identifies which accidents have significant
consequences and which accidents do not. Accident analysis information can
appear in many documents (e.g., an emergency plan, fire protection plan,
integrated safety analysis summary, environmental assessment). General
information may be acceptable, but details should be withheld.
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(3) Withhold information identifying the exact locations (e.g., detailed floor plans) of
radioactive and hazardous material whose release or theft could allow
adversaries to create a diversion for the theft of material or could result in a
significant consequence. Planning a sabotage activity (e.g., bombing a building)
would likely require less detailed information than planning a theft, for which
exact locations would likely be necessary.
RIS 2005-31, Rev. 1
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APPENDIX 2
DECOMMISSIONING AND LOW-LEVEL WASTE SITE REVIEW
NRC Contact: Division of Decommissioning, Uranium Recovery, and Waste Programs
(DUWP), Office of Nuclear Material Safety and Safeguards
DECOMMISSIONING AND LOW-LEVEL WASTE SITE CRITERIA
Note that U.S. Nuclear Regulatory Commission (NRC) Regulatory Issue Summary 2005-26,
Control of Sensitive Unclassified Nonsafeguards Information Related to Nuclear Power
Reactors, dated November 7, 2005, informs licensees of the appropriate handling of sensitive
unclassified nonsafeguards information for decommissioning reactors.
The following criteria apply:
(1) Diffuse contamination consists of soil, ground water, and surface contamination on and
in buildings, including that which is on equipment, floors, walls, and other surfaces. It
also could include volumetrically contaminated materials whose concentrations are
sufficiently low.
For determining whether only diffuse contamination is present at a decommissioning
site, apply the following information derived from the International Atomic Energy
Agencys Code of Conduct on the Safety and Security of Radioactive Sources (Code of
Conduct) (ADAMS Accession Number ML043270621) (see Table 2). Category 3 sources
in the Code of Conduct are typically about 1 curie. (The NRC is developing a
rulemaking to control the import and export of such sources.) At a concentration of
2,000 picocuries per gram, which is well above the concentrations of plutonium typically
found in soil at sites undergoing decommissioning, this equates to approximately 15,000
cubic feet of material, which is well in excess of the amount a terrorist could reasonably
use for malevolent purposes. For materials at the Class A limit for plutonium
(10 nanocuries per gram) in Title 10 of the Code of Federal Regulations
(10 CFR) Part 61, Licensing Requirements for Land Disposal of Radioactive Waste,
the volume of waste that would contain the Category 3 activity limit for plutonium would
be 3,000 cubic feet, which is also in excess of the amount a terrorist could reasonably
use. However, for cobalt-60, the amount of loose material or rubble at the Class A limit
(700 curies per cubic meter) containing the Category 3 quantity (about 1 curie) would be
less than 0.1 cubic foot, which is an amount that could easily be used for malevolent
purposes because of its small volume.
Reviewers should apply values taking into consideration the examples given above in
determining whether a decommissioning site is within the threshold values.
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GENERAL GUIDANCE FOR DECOMMISSIONING AND LOW-LEVEL WASTE SITES
Most sites undergoing decommissioning are expected to be below the threshold values in Table
2, such that most licensing documents can be released. Sensitivity reviews must be conducted
on documents related to low-level waste storage, safety, and security systems and procedures.
Reviews should focus on determining whether the information contained in these documents
could be useful to an adversary in planning a terrorist act. Examples include the location and
security arrangements for high-activity waste, the location of highly activated components, or
the transportation security arrangements for high-activity waste or activated components.
For fuel cycle, materials, and spent fuel pool and independent spent fuel storage installation
licensees that are undergoing decommissioning, issues that are not unique to decommissioning
(e.g., descriptions of plant processes, vulnerability/security assessments) should be reviewed
with regard to Appendices 1, 3, and 4, respectively.
A. Descriptions of Facilities Where Licensed Material May Be Located
(1) Withhold information identifying the exact locations of radioactive material
(e.g., detailed drawings or maps of facilities, room numbers and locations, and
specific locations of waste storage/processing operations).
(2) Withhold design information that could reasonably be expected to be useful to
potential adversaries. Examples include detailed drawings or maps showing the
locations of security measures/operations and infrastructure, locations of critical
site infrastructure (electrical or power systems), and the design of facilities that
could be useful in developing approaches to breech the facility.
(3) Withhold procedures for the receipt of low-level waste at a waste facility or
processing site.
(4) For transportation package information provided in connection with
decommissioning or low-level waste disposal licensing, consider Appendix 4 for
sensitivity of the information.
RIS 2005-31, Rev. 1
Page 14 of 23 .
APPENDIX 3
REVIEWS OF MEDICAL, INDUSTRIAL, AND ACADEMIC USERS
OF NUCLEAR MATERIALS
NRC Contact: Division of Material Safety, State, Tribal, and Rulemaking Programs, Office of
Nuclear Material Safety and Safeguards
A. Descriptions of Facilities Where Licensed Material May Be Located (Equals or Exceeds
the Threshold Values in Table 2)
(1) Copies of Licenses and Mailing Lists
(a) For copies of licenses, release authorized radionuclides and form.
Withhold authorized quantities. Withhold manufacturers and model
numbers of sealed sources and devices. Withhold information that
identifies buildings or rooms where radioactive material is located. (This
may be in the license condition that specifies the authorized location.)
(b) Withhold mailing lists that are compiled for security purposes or that
identify facilities that may have quantities of radioactive material that
equals or exceeds the threshold values listed in Table 2 or vulnerable
facilities such as those that possess material that equals or exceeds the
threshold values in Table 2 but do not aggregate the material.
(c) Release individual mailing addresses and the street address where
material is located (normally included on licenses).
(2) Locations of Radioactive Material
(a) Withhold lists of authorized or actual inventories of radionuclides.
(b) Withhold building numbers and room numbers (other than mailing
addresses) or similar information that identifies the locations of material.
(c) Withhold site drawings that identify individual buildings on the licensee
site.
(d) Withhold building drawings that identify the location of radioactive
material or onsite pathways or routes to and from locations of radioactive
material.
(e) Release individual mailing addresses and street addresses.
RIS 2005-31, Rev. 1
Page 15 of 23 .
(3) Site-Specific Design/Description of Structures, Equipment, and Operating
Procedures
(a) Most descriptions of structures, equipment, and procedures may be
released if they are not security related.
(b) Withhold drawings of buildings, rooms, and devices in which radioactive
material is located.
(c) Withhold manufacturers and model numbers of sealed sources and
devices.
(d) Withhold information on security programs, guards, access controls, key
cards, alarms, barriers, chains, and locks.
B. Nonsite-Specific Design Information: Sealed Source and Device Catalog
(1) Release information on addresses of manufacturers/distributors.
(2) Establish a password system for sensitive information for users who have with a
valid need to know and who have agreed to protect the information from
unauthorized disclosure.
C. Emergency Planning/Fire Protection Information
(1) Release general descriptions of emergency procedures for safety-related events,
such as radioactive material spills, releases, contamination, and fires.
(2) Withhold information on routes to and from locations of radioactive material.
(3) Withhold information related to responses to security events and malevolent
events.
(4) Withhold information on responses of offsite law enforcement officials.
(5) Withhold information designated by State or local governments as sensitive.
D. Security Program Information
(1) For applicable licensees
(a) Under Title 10 of the Code of Federal Regulations (10 CFR) 37.43(d),
licensees limit access to, and unauthorized disclosure of, their security
plan, implementing procedures, and the list of individuals that have been
approved for unescorted access.
RIS 2005-31, Rev. 1
Page 16 of 23 .
(b) Under 10 CFR 37.77(f), individuals who receive schedule information
related to shipments of Category 1 material, as identified in Appendix A,
Category 1 and Category 2 Radioactive Materials, to 10 CFR Part 37,
Physical Protection of Category 1 and Category 2 Quantities of
Radioactive Material, are required to limit access to, and unauthorized
disclosure of, that information.
(2) Withhold any security information that is related to malevolent events or
suspicious incidents or that could be useful to potential adversaries. Examples
include information on guards, access controls, key cards, alarms, barriers,
chains, and locks.
E. Vulnerability and Security Assessments and Accident Analyses
There is no additional guidance for medical, industrial, and academic users of nuclear
material for this category.
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APPENDIX 4
SPENT FUEL/TRANSPORTATION REVIEWS
NRC Contact: Division of Spent Fuel Management, Office of Nuclear Material Safety and
Safeguards
A. Descriptions of Facilities Where Licensed Material Is Located
SUBJECT DISCUSSION AND TYPICAL CONTROLS
10 CFR Part 72 Specific Independent ReleaseInformation provided to the U.S. Nuclear
Spent Fuel Storage Installation (ISFSI) Regulatory Commission (NRC) for specific ISFSI
Licenses and General Licenses licenses and general licenses that typically consists of
analyses to show that the design feature will withstand
- Text descriptions of the following: the combinations of forces associated with
general description, site design-basis events and natural hazards. The
characteristics, principal design analyses do not typically provide realistic information
criteria, storage cask design, on the failure of structural features and are not
operations, waste management, considered sensitive.
radiation protection, accident
analyses, conduct of operations,
operating controls and limits, and
quality assurance (QA)
10 CFR Part 72 Specific ISFSI Potentially WithholdDecisions on the control of
Licenses and General Licenses information that shows the plant site and buildings are
dependent on the level of detail. Information on
- Drawings and locations of related aspects clearly visible from locations accessible to the
hazards public near the site is generally released. This
includes general (low resolution) layout drawings of the
site and adjacent areas. Drawings showing details
such as the specific locations of equipment within
buildings, doorways, stairways, storage areas, and
other such areas are to be withheld under
10 CFR 2.390(d). Drawings showing locations of
hazards in relation to the ISFSI are also withheld. A
text description of the hazards in relation to the ISFSI
is uncontrolled and will not be reviewed.
10 CFR Part 72 Specific ISFSI WithholdInformation related to nonnuclear facilities
Licenses and General Licenses located near the ISFSI such as pipeline data (usually
withheld per the U.S. Department of Transportation
- Nearby industrial, transportation, (DOT)) and chemical facilities (some data withheld per
and military facilities the U.S. Environmental Protection Agency (EPA)) is
controlled. Other information may be protected by
other Federal agencies (e.g., U.S. Department of
Homeland Security, Federal Energy Regulatory
10 CFR Part 72 Specific ISFSI ReleaseInformation related to radionuclides, form,
Licenses and General Licenses and quantities.
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B. Nonsite-Specific Design Information: Transportation Packages and Spent Fuel Casks
SUBJECT DISCUSSION AND TYPICAL CONTROLS
10 CFR Part 71 Transportation ReleaseInformation provided to the NRC typically
Package Descriptions consists of analyses to show that the design features will
withstand the combinations of forces associated with
- Text descriptions, including design-basis events and natural hazards. The analyses do
radionuclide form, content, and not typically provide realistic information on the failure of
quantity structural features and are not considered sensitive.
Text descriptions on the design of transportation packages
do not need to be controlled because (1) 10 CFR Part 71
does not authorize possession of byproduct, source, or
special nuclear material, (2) package design information is
required for commerce both domestically and
internationally, and (3) the information that could
reasonably be expected to be useful to terrorists in
planning or executing an attack for transportation
packages containing large quantities of byproduct, source,
or special nuclear material is controlled by other means
(e.g., route controls, escort requirements, and other means
in accordance with the Commissions orders, interim
compensatory measures, or other applicable
requirements).
10 CFR Part 71 Drawings Potentially WithholdWithhold diagrams showing detailed
design information. Do not withhold drawings that have
already been made public through Freedom of Information
Act (FOIA) requests, hearings, rulemakings, or other public
forums.
10 CFR Part 71 Transportation QA ReleaseAn entity wishing to use or fabricate an approved
Program Plan Descriptions transportation package must submit a description of its QA
program to the NRC. This submittal is assigned a
10 CFR Part 71 docket and reviewed and approved by the
staff. The QA program description typically does not
contain the type of information found in the generic criteria
that would cause it to be controlled. In addition, filing and
approving a QA program description does not authorize
possession of byproduct, source, or special nuclear
material.
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SUBJECT DISCUSSION AND TYPICAL CONTROLS
10 CFR Part 71 Package Release
Information (as related to
radionuclides and their form and
quantities)
10 CFR Part 71 Advance Release unless waste shipment is Category 1 material
Notification of Shipments of subject to 37.77(f) -- Under 10 CFR 71.97, the NRC
Irradiated Reactor Fuel and requires advance notifications to the governor of a State, or
Nuclear Waste the governors designee, and to Tribal officials, of certain
shipments of high-risk radioactive material. Notification of
shipments of irradiated reactor fuel in quantities less than
those subject to 73.37(f) has been moved to 73.35, which
requires licensees to follow the requirements of Subpart D
of Part 37.
10 CFR Part 72 Dry Cask Storage ReleaseInformation provided to the NRC typically
Systems consists of analyses to show that the design features will
withstand the combinations of forces associated with
- Certificates of Compliance design-basis events and natural hazards. The analyses do
safety analysis report not typically provide realistic information on the failure of
information structural features and are not considered sensitive.
Text information in the safety analysis report, including
design information, is not controlled because (1) the design
of the casks are simple by nature, and the criteria for which
they are designed are widely known, (2) most cask designs
involve storage of the casks in open areas on concrete
pads that are often readily seen from offsite locations, and
(3) this information has been historically released to the
public to support rulemaking for approved cask designs and
other public outreach efforts.
10 CFR Part 72 Dry Cask Storage Potentially WithholdWithhold diagrams showing detailed
Systems design information. Do not withhold drawings that have
already been made public through FOIA requests, hearings,
- Drawings rulemakings, or other public forums.
10 CFR Part 72 Package Release
Information (as related to
radionuclides and their form and
quantities)
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C. Emergency Planning Information
SUBJECT DISCUSSION AND TYPICAL CONTROLS
10 CFR Part 72 Specific ISFSI ReleaseMost information related to emergency planning
Licenses and General Licenses will not need to be designated as sensitive. Special
attention is needed to determine whether information
- Emergency planning relates to the response by a licensee or Government
agency to a terrorist attack. Note that some State and local
governments consider parts of their emergency plans to be
sensitive.
D. Security Program Information
SUBJECT DISCUSSION AND TYPICAL CONTROLS
10 CFR Part 72 Specific ISFSI Potentially WithholdInformation related to security
Licenses and General Licenses programs is generally designated as Safeguards
Information or Safeguards InformationModified Handling
- Security and is protected in a manner similar to classified
confidential information. Security-related information within
the inspection and oversight program is withheld from public
disclosure under 10 CFR 2.390(d).
E. Vulnerability and Security Assessments, Accident Analyses, and Risk Assessments
SUBJECT DISCUSSION AND TYPICAL CONTROLS
Vulnerability/Security WithholdVulnerability/security assessments used to
Assessments determine the ability of transportation packages, dry cask
storage systems, or ISFSIs to withstand events from
- 10 CFR Part 71 malevolent acts have been and will continue to be withheld
transportation package designs from public disclosure.
- 10 CFR Part 72 dry cask
storage systems
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APPENDIX 5
EXPORT/IMPORT LICENSING
NRC Contact: Office of International Programs
(1) On a case-by-case basis that documents compelling reasons, withhold information on
authorized quantities or actual inventories of radionuclides that equal or exceed the
threshold values in Table 2, mixed-oxide materials, and enriched uranium above
6 percent unranium-235. Release information identifying radionuclides and form.
(2) For quantities that equal or exceed the threshold values in Table 2, withhold information
on projected or actual shipment schedules, delivery dates, date required, mode of
transport, storage arrangements, or any other related logistical information provided by
the licensee in the application or added by the U.S. Nuclear Regulatory Commission.
RIS 2005-31, Rev. 1
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Table 2 Radionuclide Screening Threshold Values
QUANTITY OF CONCERN1
RADIONUCLIDE QUANTITY OF CONCERN2 (Ci)
(TBq)
Am-241 0.06 1.6
Am-241/Be 0.06 1.6
Cf-252 0.02 0.54
Cm-244 0.05 1.4
Co-60 0.03 0.81
Cs-137 0.1 2.7
Gd-153 1 27
Ir-192 0.08 2.2
Pm-147 40 1080
Pu-238 0.06 1.6
Pu-239/Be 0.06 1.6
Ra-226 0.04 1.1
Se-75 0.2 5.4
Tm-170 20 540
Yb-169 0.3 8.1
Combinations of radioactive
See footnote below4
materials listed above3
1
The activity of multiple aggregated sources should be included when the total activity exceeds the quantity of
concern.
2
Terabecquerel (TBq) values are the regulatory standard. Curie values are provided for convenience only and
have been rounded to two significant figures.
3
Radioactive materials are to be considered aggregated if breaching a common physical security barrier (e.g., a
locked door at the entrance to a storage room) would allow access to the radioactive material or devices
containing the radioactive material. See the definition of aggregated in 10 CFR Part 37 and related guidance in
NUREG-2155, Implementation Guidance for 10 CFR Part 37, Physical Protection of Category 1 and Category 2
Quantities of Radioactive Material, Revison 1, January, 2015.
4
For calculations concerning multiple sources or multiple radionuclides, the licensee must use the following
sum-of-fractions methodology to evaluate combinations of multiple sources or multiple radionuclides when
determining whether a location equals or exceeds the threshold values and, therefore, is subject to the guidance in
this document:
RIS 2005-31, Rev. 1
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(1) If multiple sources of the same radionuclide or multiple radionuclides are aggregated at a location,
the licensee must determine the sum of the ratios of the total activity of each of the radionuclides
to verify whether the activity at the location is less than the values in Table 2. If the calculated
sum of the ratios, using the equation below, is greater than or equal to 1.0, the applicable
recommendations of this RIS apply.
(2) First, determine the total activity for each radionuclide from Table 2 by adding the activity of each
individual source, the material in any device, and any loose or bulk material that contains the
radionuclide. Then, use the equation below to calculate the sum of the ratios by inserting the total
activity of the applicable radionuclides from Table 2 in the numerator of the equation and the
corresponding threshold values from Table 2 in the denominator of the equation. The licensee
must perform the calculations in metric values (i.e., TBq); the numerator and denominator values
must be given in the same units.
/ 1.0
=1
where:
R1 = total activity for radionuclide 1
R2 = total activity for radionuclide 2
Rn = total activity for radionuclide n
AR1 = threshold value for radionuclide 1
AR2 = threshold value for radionuclide 2
ARn = activity threshold value for radionuclide n