Oxygen15WaterQualityChecker

URS & FS — User Requirements and Functional Specification

This document describes the controlled interface and behaviour of Oxygen15WaterQualityChecker for Oxygen-15 Water.

Domain limits and critical parameters

• ℹ️ Utility checks critical parameters of [15O]Water:
• • Radionuclidic purity (≥99.5%)
• • Nitrogen-13 impurity (≤1.0%)
• • Fluorine-18 impurity (≤0.1%)
• • Radiochemical purity (≥99%)
• • pH (4.5–8.5), endotoxins, sterility
• ⚠️ CRITICAL: N-13 impurity >1.0% distorts first-pass kinetics!
• F-18 impurity >0.1% creates long-term radioactive background!
• BatchNumber,TotalActivityMBq,RadionuclidicPurityPercent,Nitrogen13ImpurityPercent,Fluorine18ImpurityPercent,RadiochemicalPurityPercent,pH,EndotoxinsEU,SterilityTest,HeavyMetalsPPM,ProductType
• Example (sterility: 0=sterile, 1=contaminated):
• • Free diffusion: Crosses blood-brain barrier and cell membranes without restriction
• ⚠️ CRITICAL:
• • Radiochemical purity ≥99% — Any other oxygen forms (gas, peroxides) or impurities do not behave like water, critically distorting the single-tissue compartment model.
• • Nitrogen-13 impurity ≤1.0% — N-13 (T½=10 min) is often formed in the target. Due to longer half-life, it accumulates in blood and tissues differently than water, distorting the initial phases of the input-output curve.

URS — User Requirements Specification

input.csv contract

BatchNumber,TotalActivityMBq,RadionuclidicPurityPercent,Nitrogen13ImpurityPercent,Fluorine18ImpurityPercent,RadiochemicalPurityPercent,pH,EndotoxinsEU,SterilityTest,HeavyMetalsPPM,ProductType
O15-H2O-2026-001,20000.0,99.9,0.05,0.001,99.9,6.0,10.0,0,0.5,Perfusion_PET
O15-H2O-2026-002,18000.0,99.0,1.5,0.2,98.0,6.5,150.0,0,5,Perfusion_PET
O15-H2O-2026-003,22000.0,99.95,0.02,0.0005,99.95,5.8,5.0,0,0.2,Perfusion_PET

FS — Functional Specification

Example output.json

{
  "utilityId": "oxygen15-water-quality-checker",
  "api": "Oxygen-15 Water",
  "overallStatus": "PASS|WARNING|FAIL",
  "sourceFile": "input.csv",
  "checks": [
    {
      "parameter": "BatchNumber",
      "value": "O15-H2O-2026-001",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    },
    {
      "parameter": "TotalActivityMBq",
      "value": "20000.0",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    },
    {
      "parameter": "RadionuclidicPurityPercent",
      "value": "99.9",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    },
    {
      "parameter": "Nitrogen13ImpurityPercent",
      "value": "0.05",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    },
    {
      "parameter": "Fluorine18ImpurityPercent",
      "value": "0.001",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    },
    {
      "parameter": "RadiochemicalPurityPercent",
      "value": "99.9",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    },
    {
      "parameter": "pH",
      "value": "6.0",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    },
    {
      "parameter": "EndotoxinsEU",
      "value": "10.0",
      "status": "PASS|WARNING|FAIL",
      "message": "Rule-based check result"
    }
  ],
  "criticalFindings": []
}

OQ/PQ test scenarios

QA/QC and change control

• Do not rename columns without updating the validator and test set.
• Retain input.csv, output.json, executable version and checksum.
• Before production use, perform IQ/OQ/PQ or equivalent CSV/CSA verification.
• Critical radiopharmaceutical limits must be verified against the approved specification and local SOPs.