Gasoline isn’t under pressure, even without a spark natural gas presents an explosion hazard. Notice when we transport gas tanks today the vehicle has to have warning labels.
Can you explain what you mean?
Natural Gas has a low and quite limited air/fuel ratio mix to be ignitable.
The same type of warning labels are on gasoline tanker trucks as well.
==>”...even without a spark natural gas presents an explosion hazard.”<==
A small fraction of the hazard presented by Hydrogen! The explosion hazard is represented by the range between the Lower Explosive Limit (LEL) and Upper Explosive Limit (UEL). For gasoline, the numbers are 1.4% and 7.6%, range 6.2. For Methane (nat. gas.) they are 5%, 15%, and 10. For Hydrogen, they are 4%, 75%, and 71! Only a very few fuel gases exceed that range - Table at ( http://www.engineeringtoolbox.com/explosive-concentration-limits-d_423.html ).
However, the total hazard should also reference the leakage hazard for Hydrogen, which is lighter - and leakier - than any other molecule. In addition, Hydrogen is chemically a metal. It can penetrate some metal tanks and pipes, and weaken them to the point of failure.