Table: Hazard scales and indices
We use a traffic light system to evaluate various hazards, with each hazard having its own levels within categories such as No or Very Low, Low, Medium, High, or Very High.
Hazard | Zone value | Range | Risk Level Traffic Light |
Earthquake | 0 | MM V and below (Richter: below 4, shaking: light, damage: very light) | No or Very Low |
| 1 | MM VI (Richter: 4 — 4.6, shaking: strong, damage: light) | Low |
| 2 | MM VII (Richter: 4.6 — 5.4, shaking: very strong, damage: moderate) | Medium |
| 3 | MM VIII (Richter: 5.4 — 6, shaking: severe, damage: moderate/heavy) | High |
| 4 | MM VIIX and above (Richter: 6 and above, shaking: violent, damage: heavy) | Very High |
Volcanoes | -1 | No hazard | No or Very Low |
0 | Unclassified | No or Very Low | |
1 | Minor hazard (> 15,000 years return period) | Medium | |
2 | Moderate hazard (200 — 15,000 years return period) | Medium | |
3 | High hazard (≤ 200 years return period) | Very High | |
Tsunami | -1 | No hazard | No or Very Low |
0 | Minimal Flood Risk | No or Very Low | |
1000 | 1000 year return period (0.1% annual flood chance) | Low | |
500 | 500 year return period (0.2% annual flood chance) | Medium | |
100 | 100 year return period (1% annual flood chance) | Very High | |
Tropical Cyclone | -1 | No hazard | No or Very Low |
0 | 76 — 141 km/h | No or Very Low | |
1 | 142 — 184 km/h | Low | |
2 | 185 — 212 km/h | Medium | |
3 | 213 — 251 km/h | Medium | |
4 | 252 — 299 km/h | High | |
5 | > 300 km/h | Very High | |
Extratropical Storm | -1 | No hazard | No or Very Low |
0 | < 80 km/h | No or Very Low | |
1 | 81 — 120 km/h | Low | |
2 | 121 — 160 km/h | Low | |
3 | 161 — 200 km/h | Medium | |
4 | > 200 km/h | Very High | |
Hail | 1 | Zone 1: low | No or Very Low |
2 | Zone 2 | Low | |
3 | Zone 3 | Medium | |
4 | Zone 4 | Medium | |
5 | Zone 5 | High | |
6 | Zone 6: high | Very High | |
Tornado | 1 | Zone 1: low | No or Very Low |
2 | Zone 2 | Low | |
3 | Zone 3 | High | |
4 | Zone 4: high | Very High | |
Lightning | 1 | 0.2 — 1 | No or Very Low |
2 | 1— 4 | No or Very Low | |
3 | 4 — 10 | Low | |
4 | 10 — 20 | Medium | |
5 | 20 — 40 | High | |
6 | 40 — 80 | Very High | |
Wildfire | -1 | No hazard | No or Very Low |
1 | Zone 1: low | No or Very Low | |
2 | Zone 2 | Low | |
3 | Zone 3 | High | |
4 | Zone 4: high | Very High | |
River Flood | 0 | Minimal flood risk (Areas outside the 0.2% annual chance floodplain) | No or Very Low |
500 | 500 year return period (1% annual chance flood event) | Medium | |
100 | 100 year return period (0.2% annual chance flood event) | Very High | |
Storm Surge | -1 | No hazard | No or Very Low |
1000 | Minimal flood risk (0.1% annual flood chance) | Low | |
500 | 500 year return period (0.2% annual flood chance) | Medium | |
100 | 100 year return period (1% annual flood chance) | Very High |
For more information on the above a resource guide can be downloaded here