# Control access to Safeguards Information through need-to-know and authorization > Use 10 CFR 73.21 - Protection of Safeguards Information: Performance requirements to review this narrow operational decision without extending the source beyond its stated scope. - Canonical URL: https://update.dsesecurity.com/updates/control-access-to-safeguards-information-through-need-to-know-and-authorization/ - Publisher: Detection Systems & Engineering (DSE Security) - Author: DSE Security Editorial Team - Published: 2026-08-27T12:11:54+00:00 - Modified: 2026-08-27T13:06:59+00:00 - Last reviewed by DSE: 2026-08-26 - Resource type: Checklist - DSE priority: Advisory - Topics: Access Control, Cybersecurity - Reading time: 3 minutes ## What you need to know Use 10 CFR 73.21 - Protection of Safeguards Information: Performance requirements to review this narrow operational decision without extending the source beyond its stated scope. ## Potentially affected Teams, systems, services, or facilities within the stated scope of 10 CFR 73.21 - Protection of Safeguards Information: Performance requirements ## DSE recommendation Compare the observed state with the cited official source, document applicability and exceptions, and test any approved change with rollback safeguards. ## Article Treat this document as a focused evidence review: Control access to Safeguards Information through need-to-know and authorization. Only the official source and traced locations below supply facts. Confirm applicability before acting. ## Source fact: The official [10 CFR 73.21 – Protection of Safeguards Information: Performance requirements](https://www.ecfr.gov/current/title-10/section-73.21) from U.S. Nuclear Regulatory Commission via eCFR supports the following bounded statements: - Under 10 CFR 73, covered persons must maintain an information-protection system incorporating section 73.23 safeguards for specified non-power reactors holding special nuclear material. The research record locates this support at 10 CFR 73.21(a)(1)(ii), read with 10 CFR 73.21(a)(1) (eCFR anchor p-73.21(a)(1)(ii)). - Under 10 CFR 73, Safeguards Information outside paragraphs (a)(1)(i) and (ii) must be protected under section 73.22. The research record locates this support at 10 CFR 73.21(a)(1)(iii), read with 10 CFR 73.21(a)(1) (eCFR anchor p-73.21(a)(1)(iii)). Do not import neighboring assumptions into the source record. The supported task is a scoped comparison involving credentials, readers, controllers, panels, door hardware, access decisions, monitoring, and life-safety interfaces and the conditions the source actually describes. ## What the source does not establish NRC regulation with defined information categories and covered persons; do not publish protected details, and obtain qualified review before operational use. A correct source interpretation can still be inapplicable to a particular design. Confirm identity sources, DNS where used, time, networks, power, fire systems, monitoring, and authorized operators, ownership, and change authority instead of treating documented behavior as a deployment guarantee. ## Applicability questions - For source statement 1 at 10 CFR 73.21(a)(1)(ii), read with 10 CFR 73.21(a)(1) (eCFR anchor p-73.21(a)(1)(ii)), which observable configuration, record, or test can confirm applicability here? - For source statement 2 at 10 CFR 73.21(a)(1)(iii), read with 10 CFR 73.21(a)(1) (eCFR anchor p-73.21(a)(1)(iii)), which observable configuration, record, or test can confirm applicability here? - Which deployed instance of credentials, readers, controllers, panels, door hardware, access decisions, monitoring, and life-safety interfaces will be compared with the source, and why that instance? - How will the review distinguish a source mismatch from a failure in identity sources, DNS where used, time, networks, power, fire systems, monitoring, and authorized operators? - Who approves the conclusion, exception, test window, and rollback threshold? ## DSE recommendation: DSE recommends using the cited source as the evidence anchor for this decision. Use a two-person review for the source interpretation and the resulting operational decision. Record the source location, examined part of credentials, readers, controllers, panels, door hardware, access decisions, monitoring, and life-safety interfaces, observed and expected states, owner, and reason for deviation. For an approved change, define prerequisites, a limited test path, success and stop conditions, monitoring, and rollback. Check identity sources, DNS where used, time, networks, power, fire systems, monitoring, and authorized operators in design order. Protect credentials, keys, recovery material, personal data, and sensitive topology in evidence. ## Verification and evidence Build a reproducible chain from 10 CFR 73.21(a)(1)(ii), read with 10 CFR 73.21(a)(1) (eCFR anchor p-73.21(a)(1)(ii)); 10 CFR 73.21(a)(1)(iii), read with 10 CFR 73.21(a)(1) (eCFR anchor p-73.21(a)(1)(iii)) to the observed environment. Useful domain evidence includes approved configuration exports, access-event tests, controller state, door inspections, alarm handling, and exception records; label every item with scope, timestamp, collector, and stable identifier. Retain the starting state, authorization, execution record, outcome, deviation, and final state as one review package. Move disruptive checks to an approved test path. Reopen the decision when versions, design, dependencies, ownership, or official guidance changes. ## Official references - [10 CFR 73.21 – Protection of Safeguards Information: Performance requirements](https://www.ecfr.gov/current/title-10/section-73.21) — U.S. Nuclear Regulatory Commission via eCFR ## Primary reference - Name: 10 CFR 73.21 - Protection of Safeguards Information: Performance requirements - Authority: www.ecfr.gov - URL: https://www.ecfr.gov/current/title-10/section-73.21 - Source publication date: Not stated by the source ## Citation and use Preferred citation: “Control access to Safeguards Information through need-to-know and authorization,” DSE Security, https://update.dsesecurity.com/updates/control-access-to-safeguards-information-through-need-to-know-and-authorization/ Publishing principles: https://update.dsesecurity.com/updates/dse-updates-editorial-methodology/ Usage and citation policy: https://update.dsesecurity.com/usage/ Copyright © 2026 Detection Systems & Engineering. 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