| Feature | IAEA System | UK System |
|---|---|---|
| Primary basis | Half-life of radionuclides | Activity concentration |
| Exempt waste | Yes — below clearance levels | Yes — below clearance levels |
| Low-level category | LILW-SL (short-lived, limited long-lived content) | LLW (less than 4 GBq/te alpha or 12 GBq/te beta/gamma) |
| Intermediate category | LILW-LL (long-lived radionuclides) | ILW (exceeds LLW but not heat-generating) |
| High-level category | HLW (heat-generating, above 2 kW/m^3) | HLW (decay heat significant) |
| Consistency | Directly linked to disposal route (near-surface vs geological) | Based on measurable activity concentration thresholds |
| Advantage | Simple and consistent with general practice; links classification to disposal | Clear quantitative thresholds for categorisation; well-established regulatory framework |
Lesson 6 ◆ 6.9 Radioactive Waste Classification