Don’t get caught at the last minute with a low or empty propane tank on your BBQ grill. Here’s a way to test how much fuel is in the tank: on a cold, turned off  grill, pour a few cups of boiling water over the sides of the propane tank. Carefully touch the sides of the tank. Where it feels warm it is EMPTY and where the metal feels cool is where the fuel is and you can gauge how much is left inside.