Safeguard zones
 | zone I, immediate safeguard zone |
 | zone IIA, closer safeguard zone with strongely higher vulnerability |
 | zone IIB, closer safeguard zone with higher vulnerability |
 | zone IIC, closer safeguard zone |
 | zone III, distant safeguard zone |
| zone I, immediate safeguard zone |
| zone IIA, closer safeguard zone with strongely higher vulnerability |
| zone IIB, closer safeguard zone with higher vulnerability |
| zone IIC, closer safeguard zone |
| zone III, distant safeguard zone |