Inner cordoned area (safety perimeter) for a radiological emergency.
| Situation with potentially dangerous source |
Area |
| Initial determination — outside |
| Unshielded/damaged |
30m around |
| Major spill |
100m around |
| Fire, explosion or fumes |
300m radius |
| Suspected bomb (potential RDD)
|
400m radius or more |
| Initial determination — inside a building |
| Damage, loss of shielding or spill |
Affected and adjacent areas, including floors above and below |
| Fires/other event spreading materials throughout the building |
Entire building and appropriate outside distance |
| Expansion based on radiological monitoring |
| 100 µSv/h dose rate at 1m |
Wherever these levels are measured |
