Table 3.
Comparison of factors affecting fire and explosion hazards of hydrogen vs. methane, propane, and acetylene at atmospheric conditions (
1 atm and 
298 K).
| Factor | Hydrogen vs. methane | Hydrogen vs. propane | Hydrogen vs. acetylene | Acetylene vs. methane | Acetylene vs. propane | Propane vs. methane | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Hydrogen | Methane | Hydrogen | Propane | Hydrogen | Acetylene | Acetylene | Methane | Acetylene | Propane | Methane | Propane | |
| LFL | 1 | 0 | 0 | 1 | 0 | 1 | 1 | 0 | 0 | 1 | 1 | 0 |
| UFL | 1 | 0 | 1 | 0 | 0 | 1 | 1 | 0 | 1 | 0 | 0 | 1 |
| MOC | 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 |
| Autoignition temperature | 0 | 1 | 0 | 1 | 0 | 1 | 1 | 0 | 1 | 0 | 1 | 0 |
| Minimum spark ignition energy | 1 | 0 | 1 | 0 | 0 | 1 | 1 | 0 | 1 | 0 | 0 | 1 |
| Gas density | 0 | 1 | 0 | 1 | 0 | 1 | 1 | 0 | 0 | 1 | 1 | 0 |
| Molecular size | 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 | 0 | 1 |
| Quenching distance | 1 | 0 | 1 | 0 | 0 | 1 | 1 | 0 | 1 | 0 | 1 | 0 |
| Boiling point | 1 | 0 | 1 | 0 | 1 | 0 | 0 | 1 | 1 | 0 | 0 | 1 |
| Flame speed | 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 | 0 | 1 |
| LHV | 1 | 0 | 1 | 0 | 1 | 0 | 0 | 1 | 1 | 0 | 0 | 1 |
| Adiabatic flame temperature | 1 | 0 | 1 | 0 | 0 | 1 | 1 | 0 | 1 | 0 | 1 | 0 |
| Deflagration index | 1 | 0 | 1 | 0 | 1 | 0 | 0 | 1 | 0 | 1 | 1 | 0 |
| Thermal conductivity | 1 | 0 | 1 | 0 | 1 | 0 | 0 | 1 | 1 | 0 | 0 | 1 |
| Probability factors (total) | 7 | 2 | 6 | 3 | 3 | 6 | 8 | 1 | 7 | 2 | 5 | 4 |
| Consequence factors (total) | 5 | 0 | 5 | 0 | 4 | 1 | 2 | 3 | 4 | 1 | 2 | 3 |
| Sum of factors | 12 | 2 | 11 | 3 | 7 | 7 | 10 | 4 | 11 | 3 | 7 | 7 |