There was an explosion and fire at an Arroyo Grande home on Friday. It now looks like the company that serviced their propane tanks earlier in the day didn't close a valve and the gas collected in the garage and then ignited. It also sounds like the water heater wasn't at least 18" off the ground as you're supposed to have. The theory is that the propane would be able to evacuate so you wouldn't get an explosion like what happened in this case.