System

Operator-queued system: {{entity:Radio Chemistry Laboratory for a UK Nuclear Dockyard}}, classified {{hex:54853859}}. This is a radiochemistry facility at a UK Royal Navy nuclear dockyard providing analytical services for submarine reactor maintenance — coolant activity analysis, fuel integrity assessment, waste characterisation, and environmental discharge monitoring. Operating under ONR Nuclear Site Licence and DNSR governance, the laboratory handles alpha/beta/gamma spectrometry, liquid scintillation counting, radiochemical separations, and ICP-MS for trace actinide analysis. Scaffolding session — project se-radiochem-lab created with 7 documents (6 standard plus Hazard Analysis), 5 trace linksets, and full subsystem decomposition.

Decomposition

The laboratory decomposes into 12 subsystems reflecting the real functional organisation of a nuclear analytical facility. The analytical chain runs from sample receipt through radiochemical preparation to four distinct measurement techniques, each requiring different detector technologies and sample preparation protocols. Supporting subsystems handle containment, effluent treatment, waste management, radiation protection, and data management.

Subsystems classified in SE:radiochem-lab:

• {{entity:Sample Receipt and Preparation Laboratory}} {{hex:00843A59}} — front-end chain of custody and sample preparation
• {{entity:Gamma Spectrometry Suite}} {{hex:54E53058}} — HPGe detectors for gamma-emitting fission and activation products
• {{entity:Alpha Spectrometry Laboratory}} {{hex:54843018}} — PIPS detectors for actinide alpha measurement
• {{entity:Liquid Scintillation Counting Facility}} {{hex:54E51059}} — dual-PMT coincidence counting for tritium and beta emitters
• {{entity:ICP-MS Analysis Suite}} {{hex:54E53058}} — quadrupole/sector-field mass spectrometry for trace actinide isotopics
• {{entity:Radiochemical Separations Laboratory}} {{hex:40853219}} — ion exchange, solvent extraction, electrodeposition
• {{entity:Hot Cell Facility}} {{hex:DE851059}} — shielded containment for high-activity sample handling
• {{entity:Ventilation and Containment System}} {{hex:55D73859}} — HEPA-filtered extract ventilation and pressure cascade
• {{entity:Active Effluent Treatment Plant}} {{hex:57D73A59}} — liquid effluent collection, treatment, and monitored discharge
• {{entity:Solid Radioactive Waste Management System}} {{hex:42A53A5D}} — waste characterisation, segregation, and packaging
• {{entity:Radiation Protection and Health Physics System}} {{hex:54E57859}} — dosimetry, area monitoring, contamination control
• {{entity:Laboratory Information Management System}} {{hex:50AD7B58}} — sample tracking, QA/QC, result management

flowchart TB
  RCL["Radio Chemistry Laboratory"]
  SRP["Sample Receipt and Preparation"]
  GS["Gamma Spectrometry Suite"]
  AS["Alpha Spectrometry Laboratory"]
  LSC["Liquid Scintillation Counting"]
  ICP["ICP-MS Analysis Suite"]
  RS["Radiochemical Separations"]
  HC["Hot Cell Facility"]
  VC["Ventilation and Containment"]
  AET["Active Effluent Treatment"]
  SWM["Solid Waste Management"]
  RP["Radiation Protection"]
  LIMS["LIMS"]

  RCL --> SRP
  RCL --> GS
  RCL --> AS
  RCL --> LSC
  RCL --> ICP
  RCL --> RS
  RCL --> HC
  RCL --> VC
  RCL --> AET
  RCL --> SWM
  RCL --> RP
  RCL --> LIMS

Notable hex code convergence: {{entity:Gamma Spectrometry Suite}} and {{entity:ICP-MS Analysis Suite}} both classified to {{hex:54E53058}}, reflecting their shared traits as powered, observable, intentionally designed analytical measurement systems. The {{entity:Hot Cell Facility}} at {{hex:DE851059}} stands out with its Structural and Physical Object traits — the only subsystem with significant shielding mass.

Analysis

Cross-domain exploration revealed that {{entity:Active Effluent Treatment Plant}} maps to {{entity:Water Treatment Plant}} at 97% Jaccard similarity — unsurprising given both perform liquid treatment with chemical precipitation and filtration. The {{entity:Hot Cell Facility}} matched structural entities from the defence domain (Chobham Armor at 97%) and civil engineering (dams, water bridges), reflecting the dominance of physical shielding in its trait profile rather than any analytical function.

The system context diagram maps 6 external actors: Submarine Reactor Compartment (sample source), Dockyard Operations (scheduling/results), ONR/DNSR (regulatory oversight), Environment Agency (discharge permits), Waste Disposal Contractor (waste consignment), and National Nuclear Laboratory (reference standards and proficiency testing).

Lint returned zero findings on the initial 20 requirements. Zero orphaned requirements — all 12 SYS requirements trace to at least one STK requirement.

Requirements

8 stakeholder requirements capture needs from 6 stakeholder groups: dockyard operations ({{stk:STK-NEEDS-001}} 24-hour turnaround), regulators ({{stk:STK-NEEDS-002}} licence compliance, {{stk:STK-NEEDS-003}} discharge limits), workers ({{stk:STK-NEEDS-004}} ALARP dose), accreditation bodies ({{stk:STK-NEEDS-005}} ISO 17025), waste disposal ({{stk:STK-NEEDS-006}} WAC compliance), criticality safety ({{stk:STK-NEEDS-007}}), and fleet programme ({{stk:STK-NEEDS-008}} 95% availability).

12 system requirements derived with full traceability. Key performance requirements: {{sys:SYS-REQS-001}} gamma MDA <1 Bq, {{sys:SYS-REQS-002}} tritium MDA <5 Bq/L, {{sys:SYS-REQS-003}} hot cell dose rate <7.5 μSv/h, {{sys:SYS-REQS-005}} effluent alpha <0.1 Bq/L, {{sys:SYS-REQS-007}} fissile material limit 50g per area with safe-geometry vessels, {{sys:SYS-REQS-010}} stack monitoring at 10% of derived air concentration limits.

Next

First decomposition session should prioritise the {{entity:Hot Cell Facility}} and {{entity:Radiochemical Separations Laboratory}} — these are the highest-risk subsystems with the most complex internal interfaces (manipulators, transfer ports, active drains, containment barriers). The analytical measurement subsystems (gamma, alpha, LSC, ICP-MS) are lower risk but will need component-level decomposition covering detector systems, calibration, and data acquisition chains. Cross-subsystem interfaces — particularly the sample flow from Hot Cell through Separations to the measurement suites — are critical and not yet defined.