Glossary:
| AGR | Advanced Gas-Cooled Reactor (UK) |
| BWR | Boiling Water Reactor |
| CANDU | Canadian Deuterium Uranium Reactor |
| Ci/km2 | Old Unit for the ground contamination; 1 Ci/km2 = 37 kBq/m2 |
| Cs-137 | Caesium-137; Cs-137 has a half-life time of 30.2 years and is therefore an indicator for the long time radiological effects. |
| FBR | Fast Breeder Reactor |
| GCR | Gas Cooled Reactor (UK) |
| IAEA | International Atomic Energy Agency |
| IAEA-Scenario | The International Nuclear Safety Advisory Group, which is a working group established in the IAEA, has formulated in the INSAG-3 report in 1988 a minimal safety target for the existing NPPs: The frequency of large off-site releases of radioactivity should not exceed 10E-5 per reactor year (1 accident within 100 000 years). Even today, more than ten years later, not all operating NPPs meet this safety target. In the IAEA scenario the release frequency for all NPPs is defined as 10E-5 per reactor year. INSAG International Nuclear Safety Advisory Group; Reports INSAG 1-10. |
| kBq/m2 | New unit (SI) for the ground contamination. |
| NPP | Nuclear Power Plant |
| RBMK | Reaktor Bolshoi Moshchhnoski Kanalkni (High-Power Channel Type Reactor); Chernobyl-type reactor |
| RT-Scenario | In the Reactor Type scenario a generic release frequency (for large off-site releases of radionucludes) for a specific type of reactor is defined. Facility-specific differences (such as ageing, different safety systems and containment types, external hazards,…) are not taken into account. For a reactor specific scenario the accidental release frequencies from a level 2 PSA have to be known for every of the more than 200 operating reactors in Europe. |
| PWR | Pressurized Water Reactor |
| WWER | Vodo-Vodyannoy Energeticheskiy Reactor (water-cooled, water-moderated, reactor; Russian PWR) |