Gas Explosions: Migration Precautions
Exercise extreme caution when approaching and entering the scene of an explosion.
Be aware there may be multiple buildings with gas levels in the explosive range and/or additional gas trapped in the location where the initial explosion occurred. And keep in mind that gas could possibly be leaking before a valve, so shutting off the valve may not mitigate the problem.
In extreme or prolonged situations, the electricity should be turned off to the structures or area involved.