A story about gasoline fumes ….
About 25 years ago, the local police force was a participant in our regional “Marine Safety Day”. A grand event which drew several thousand people from all around. One of the attractions was the demonstration of a “bilge fume explosion”. To accomplish this, the demolitions division of the police obtained a derelict 28 foot wood construction enclosed cabin power boat. It was towed and moored in the otherwise closed harbour. They closed off the boat, and left a 5 liter jerry can of gasoline to evaporate all morning. A small detonator of some type was controlled by wire to shore.
My job was to operate our fireboat. I rafted up to the two police boats a safe distance back, with my crew, all geared up and ready! The police Sargent said to me: “When it blows up, don’t rush right in and put out the fire, let it get going for effect, so the crowd can see”. Fair enough, I replied, I’ll wait right here, and you tell me when to go in and extinguish the fire…”.
3, 2, 1…. Blammo! An immense fireball emanated from the boat, and the shock wave hit us (and the crowd, I presume) with a thump. I looked at the boat, as the smoke cleared, to judge the fire we were about to be asked to extinguish, and there was nothing there. The entire 28 foot boat was gone above the waterline, planks and splinters blown hundreds of feet away. I turned to the Sargent, as we both viewed the smouldering, and now sinking remaining hull, and asked: “shall we go now and put out the fire? Or, shall we let it burn for a while first?”. His return look indicated to me that they had not planned to blow the boat to bits, but rather just start a fire.
We spent all afternoon gathering up all the floating debris, all those planks with nails sticking out like angry porcupines being carry to shore across the tubes of our two Zodiac boats!
The explosive power of the vapour from a few liters of gasoline is not to be underestimated!