I |
IIt |
IIIt |
IVt |
Vt |
VIt |
VIIt |
VIIIt |
|
Class |
1.Nearly level |
2. Gently |
3. Undulating |
4. Moderate |
2.Gent |
5. Steep |
6. Very steep |
any |
% |
≤ 2 |
≤ 8 |
≤ 16 |
≤ 30 |
≤ 8 |
≤ 50 |
≤ 75 |
any |