| Compounds | Percentage by volume (%) |
| Hydrogen (H2) | 20 |
| Carbon (ii) oxide (CO) | 25 |
| Carbon(iv) oxide (CO2) | 10 |
| Methane (CH4) | 3 |
| Higher hydrocarbon | 1 |
| Nitrogen | 40 |
| Others | 1 |
| Total | 100 |