Glossary

SEC Form 8-K

Current report on a material event, due within four business days. Grade A.

SEC quarterly / annual report

Quarterly (unaudited) and annual (audited) periodic reports. Grade A.

Acceptance and docketing

NRC finds a tendered application complete enough for detailed technical review, dockets it and usually issues a review schedule. Rung 2.

Watch for A completeness check, not an approval. Confusing acceptance with approval is red flag 7.

Advisory Committee on Reactor Safeguards

Statutory independent committee that reviews staff safety evaluations on power reactor applications and reports to the Commission.

Watch for ACRS letters are advice, not licensing actions.

Agencywide Documents Access and Management System

NRC’s public document library; records carry ML accession numbers (e.g., ML26085A071) and are the citable primary record.

Advanced (non-LWR) reactor

Statutory usage (NEIMA) covers non-LWRs and LWRs with significant improvements; on this site it means non-LWR.

Advanced Reactor Demonstration Program

DOE-NE program (2020) cost-sharing two demonstrations, TerraPower Natrium and X-energy Xe-100, largely funded through the 2021 Infrastructure Investment and Jobs Act.

Verification date

The date a row or figure was last checked against its source. Status claims without one are not used.

At-the-market offering

Issuer sells new shares into the market over time through a sales agent.

Watch for Proceeds are dilution, not revenue; repeated ATM use is red flag 6.

Behind-the-meter / co-location

Load served directly by an adjacent plant with limited use of the grid; FERC and PJM proceedings have contested cost shifting (e.g., Talen–Amazon at Susquehanna).

Deal tiers 1–3

A buyer is contractually bound: a PPA from an operating plant, a restart or uprate backed by an offtaker, or new-reactor offtake with price, volume and term.

Watch for “Agreement” in a headline is not evidence of a binding contract; check the tier.

Boiling water reactor

Steam raised in the core, direct cycle. BWRX-300.

SNM security category II

NRC physical-security category set by the quantity and enrichment of material on hand; HALEU fuel plants typically fall here, with stricter security than LEU (Category III) plants.

Combined license

Part 52 license authorizing construction and operation together. Fuel load waits for the Commission’s §52.103(g) finding that all ITAAC are met. Rung 4.

Watch for Issuance is not “approved to operate”; the 52.103(g) finding comes years later.

Commercial operation date (COD)

Plant declared available for commercial dispatch after power ascension. End of rung 5.

Construction permit

Part 50 authorization to build a facility; operation requires a separate OL. Rung 3.

Watch for Not permission to load fuel or operate; a CP holder may never reach an OL.

Construction permit number prefixes

Prefixes on the permits shown here: CPAR for power reactors (CPAR-1 Kemmerer, CPAR-2 Clinch River), CPTR for non-power test reactors (Kairos Hermes, Hermes 2), CPRR for research reactors (ACU MSRR).

Watch for A CPTR or CPRR is not a commercial power-reactor permit; don’t count Hermes as one.

Offtake strength, 1–8

How firmly a buyer is bound, from executed PPA at an operating plant (1) to a “nuclear-powered” campus with no vendor, license or fuel (8). See Method §3.

NRC docket

Case identifier. 50-: Part 50 facilities (power, test, research reactors); 52-: Part 52 design and COL reviews; 70-: fuel facility and materials licenses. Docketed records are in ADAMS.

US Department of Energy

Owns the national labs and authorizes reactors on DOE-controlled sites under its own AEA authority, with no NRC license.

(Preliminary) documented safety analysis

DOE safety basis for a nuclear facility under 10 CFR 830; the PDSA supports design and construction, the DSA supports operation.

Watch for DOE approval, not an NRC license, and it doesn’t transfer to a commercial site.

Environmental assessment / finding of no significant impact

NEPA document lighter than an EIS; a FONSI concludes no EIS is needed.

Watch for Environmental only; says nothing about the safety review.

Environmental impact statement

Full NEPA analysis; the draft goes out for public comment before the final.

Uranium enrichment

Raising the U-235 fraction above natural (0.711%), measured in SWU.

Emergency planning zone

Area with pre-planned offsite protective actions; historically about a 10-mile plume and 50-mile ingestion zone. The 2023 rule lets SMRs and other new technologies justify a scalable EPZ, possibly at the site boundary.

Watch for “Site-boundary EPZ” is a request until approved for a specific application.

Early site permit

Part 52 approval of a site’s safety, environmental and emergency-planning suitability, valid 10–20 years and renewable, without committing to a design or to build. Rung 3 when issued.

Watch for A technology-neutral ESP (Belews Creek, North Anna) means no vendor has been selected.

Source strength, A–E

A regulatory/SEC/court record; B government report, audited financials or sworn testimony; C company release; D press; E social or unverified. See Method §2.

Federal Energy Regulatory Commission

Regulates interstate transmission and wholesale power, including co-location interconnection terms.

Fluoride salt-cooled high-temperature reactor

Solid TRISO pebble fuel with molten fluoride salt (FLiBe) coolant. Kairos KP-FHR.

Initial core load

The fuel for first startup, distinct from reload supply; track whether a vendor has both.

First-of-a-kind / nth-of-a-kind

FOAK carries one-time engineering, licensing and supply-chain cost; NOAK assumes fleet learning.

Watch for A cost claim without basis year and FOAK/NOAK label is red flag 4; NOAK figures are projections.

Federal Register

Daily official publication of agency notices and rules; NRC docketing, hearing and issuance notices appear here. Grade A.

Framework / master agreement

Umbrella deal with capacity targets and no binding volumes or prices until project-level contracts. Deal tier 6 unless it carries specifics.

Watch for “Up to X GW” is a ceiling, not a commitment.

Initial fuel loading

Loading fuel into the core; for NRC plants it needs an OL or the §52.103(g) finding. Start of rung 5.

Generic Design Assessment (UK)

Voluntary ONR and Environment Agency review of a reactor design in three steps; Step 3 is the detailed assessment.

Watch for Completing GDA is not a site licence or consent to build.

High-assay low-enriched uranium

5% to under 20% U-235. Needed by most advanced designs; no commercial-scale US enrichment yet (Centrus demonstration cascade only).

Watch for Check that a HALEU claim gives enrichment, mass, chemical form and delivery date.

High-temperature gas-cooled reactor

Helium-cooled, graphite-moderated, TRISO-fueled (pebbles or prismatic compacts). Xe-100, Pele, Kaleidos, Ward 250, KRONOS MMR.

Hyperscale cloud and AI operator

Amazon, Google, Microsoft, Meta, Oracle: buyers contracting directly for firm power.

Idaho National Laboratory

DOE’s lead nuclear lab; hosts DOME, NRIC and most 2026 pilot criticalities.

Inspections, tests, analyses and acceptance criteria

COL conditions that must all be satisfied before the §52.103(g) finding permits fuel load.

k < 1 · k = 1 · k > 1

Subcritical (announced, unfunded, non-binding), critical (self-sustaining evidence) or supercritical (adding energy). The limiting factor sets the band. See Method §5.

Low-enriched uranium

Formally under 20% U-235; in industry usage, LWR fuel up to 5% (typically 3–5%).

Watch for “LEU” in a release usually means ≤5%; HALEU is technically a subset.

NRC licensing ladder, 1–5

Pre-application (1), docketed (2), permit or approval (3), OL or COL (4), fuel load through commercial operation (5). See Method §4.

Watch for Rung 1 activity is not licensing.

DOE Loan Programs Office

Issues and guarantees DOE loans for energy projects; financed the Palisades restart.

Watch for A conditional commitment is not a closed loan.

Limited work authorization

§50.10 authorization for specified safety-related construction before a CP or COL is issued.

Watch for Holtec Pioneer’s docketed Part 1 is the LWA request, not the full CP.

Light-water reactor

Ordinary water as coolant and moderator: PWRs and BWRs. The US fleet and the LWR SMRs (BWRX-300, US460, SMR-300, AP300).

Uncontested hearing

Hearing the Commission must hold before issuing certain CPs, including power reactor CPs (AEA §189a); tests the sufficiency of the staff’s review.

Watch for Holding it is not the decision; Long Mott’s was Sep 22 2026, CP still pending.

Micro reactor

Roughly 1–20 MWt (DOE usage); typically factory-complete and transportable.

Memorandum of understanding

Non-binding statement of intent. Deal tier 6.

Watch for Not a contract; often lapses quietly.

Molten salt reactor

Fuel dissolved in the salt (liquid-fueled). IMSR, ACU MSRR/MSR-1, MCFR.

Watch for Not the same as an FHR, which uses solid fuel and salt only as coolant.

Megawatts electric / thermal

MWe ≈ MWt × net efficiency (about 33% for LWRs, about 40% for HTGRs; Xe-100: 200 MWt → 80 MWe).

Watch for Bare “MW” or “GW” is ambiguous, and thermal numbers flatter small units. Also check gross vs. net and module vs. plant.

DOE, DoD and foreign authorizations

Tracked off the NRC ladder: DOE authorization at DOE sites, DoD at military installations, and foreign regulators. Hearing rights, NEPA handling and public participation differ.

Watch for A DOE-track criticality is not progress on an NRC license.

US Nuclear Regulatory Commission

Independent agency licensing commercial reactors, fuel facilities and nuclear materials under the AEA.

Nuclear safety design agreement

DOE agreement fixing a project’s safety design requirements and review approach before safety-basis documents are approved; used in the Reactor Pilot Program.

Offtake agreement

Commitment to buy a project’s output; the buyer is the offtaker.

Operating license

Part 50 authorization to load fuel and operate, issued after construction once the NRC finds the plant conforms to its application. Rung 4.

Watch for No SMR or advanced design holds one as of Oct 23 2026.

10 CFR Part 50

Two-step licensing: construction permit, then a separate operating license. Path for Kemmerer, Clinch River, Long Mott, Holtec Pioneer and all non-power test and research reactors here.

10 CFR Part 52

Standardized licensing: early site permit, design certification, standard design approval, manufacturing license and combined license; resolves design and site issues before construction.

10 CFR Part 53

Risk-informed, technology-inclusive licensing framework for advanced reactors mandated by NEIMA (2019). Rule status is not tracked on this site; confirm before citing.

Power ascension testing

Staged increase to rated power with tests at plateaus after initial criticality.

Power purchase agreement

Binding contract for energy, capacity and/or attributes at a defined price, volume and term.

Watch for Many headline “PPAs” are MOUs or frameworks; ask for executed status, price, MW, term and exit rights.

Pre-application engagement

Voluntary NRC interaction before filing: white papers, topical reports, readiness assessments, audits. No licensing action is pending. Rung 1.

Watch for “Working with the NRC” in a release usually means this, not licensing.

Pressurized water reactor

Pressurized primary loop; steam raised in a secondary loop. US460, SMR-300, AP300, AP1000, Rolls-Royce SMR, Last Energy PWR-5/-20.

DOE Reactor Pilot Program

DOE pathway (selections Aug 2025) authorizing test reactors outside the national labs under DOE authority, targeting at least three criticalities by Jul 4 2026.

Watch for DOE authorization skips NRC adjudicatory hearings; it is not a commercial license.

Plant restart

Returning a shut-down plant to service by restoring its licensing basis (amendments, exemptions, inspections) rather than a new license: Palisades, Crane (TMI-1), Duane Arnold.

Watch for A deal tier 2 arrangement; dates depend on NRC approvals and plant condition.

Standard design approval

Part 52 Subpart E staff approval of a standard design (not a rule). Referenceable in CP, OL or COL applications; less finality than a DC.

Watch for An SDA is not a DC, not a site license and not a customer order.

Safety evaluation (SER, FSER)

NRC staff’s documented technical findings on an application or topical report. A final SE precedes the licensing decision.

Watch for An SE is a staff finding, not the Commission’s licensing decision.

First-pass data

Figures from the first full pass of the tracker (Oct 23, 2026), now being re-verified row by row.

Sodium-cooled fast reactor

Liquid-sodium coolant, fast spectrum, typically metallic fuel. Natrium, Aurora.

Small modular reactor

IAEA usage: up to about 300 MWe per unit, with factory-built modules.

Watch for Used loosely: Rolls-Royce SMR (470 MWe) and Natrium (345 MWe) exceed the IAEA bound; check per-unit MWe.

Non-power reactor (AEA §104)

Licensed for testing or research rather than as a commercial (§103) facility. A §104(c) test reactor can still generate some power; Kairos claims up to 50 MWe for Hermes 2.

Watch for A non-power CP is not a commercial power-reactor CP.

Molten-salt heat storage

Natrium couples the reactor to salt heat storage so output can rise above its 345 MWe base, to about 500 MWe, for hours.

Watch for 500 MWe is a peak for hours, not continuous capacity.

Licensing topical report

Standalone technical report (method, code, design element, event set) that the NRC approves through a safety evaluation so later applications can reference it.

Watch for An approved topical report approves a piece, not a reactor or a site.

Tristructural isotropic coated particle fuel

Kernel coated with porous carbon buffer, inner pyrolytic carbon, silicon carbide and outer pyrolytic carbon; packed in pebbles or compacts and retains fission products to very high temperature.

Watch for “TRISO” doesn’t specify enrichment, kernel (UO2 vs. UCO) or fabricator; ask.

Tennessee Valley Authority

Federal power corporation; holds Clinch River ESP-006 and CPAR-2.

Utah Associated Municipal Power Systems

Joint action agency whose NuScale Carbon Free Power Project was cancelled Nov 2023 for lack of subscription.

Power uprate

License amendment raising a plant’s licensed thermal power; source of incremental MW in several hyperscaler PPAs.

Low-power physics test

First self-sustaining chain reaction at negligible thermal power; a reactor-physics test, not power operation.

Watch for Produces no electricity. Every 2026 criticality on this site was a DOE-authorized zero-power test.