quick question about fuel pumps and gas

You know I've always wondered why in-tank fuel pumps don't cause the gas to ignite. Here I am today upgrading to a 255LPH pump and I see that the terminals on the old pump are exposed to the gas inside the tank. I realize that it's safe but just out of curiosity how is it that it doesn't ignite the gas?

Air\Fuel ratio?

I'm no expert, but perhaps because the fuel pump isn't in gas, it's in a liquid. There is no oxygen to spark a bang. The fuel has to be vapors or atomized to mix with oxygen...and the spark will give you a bang.

Is that right?

Electrical current in and of itself isn't going to ignite a vapor (say tank is 1/2 full). It would require a spark with the right amount% of vapor in the tank for things to ignite. The tank usually has too much gasoline and not enough oxygen to make a good combustion.

Crazy, thanks for the info, just one of those things that always puzzled me.