| Soil Type (S) | Seismic Factors (Z) |
| Hard Rock (S1) | 0.075 gravitational acceleration (Z1) |
| Rock (S2) | 0.150 gravitational acceleration (Z2) |
| Very dense soil and soft rock (S3) | 0.20 gravitational acceleration (Z3) |
| Stiff soil ( S4) | 0.30 gravitational acceleration (Z4) |
| Soft soil (S5) | 0.40 gravitational acceleration (Z5) |