Reading your Tank Gauge:
Go to a phone that is not near the smell and call your propane company right away. (If the smell is strong or you are unsure, leave the building and then call.) They will come and make the area safe at no charge to you. While waiting for the propane company field service representative:
-Keep everyone away from the area of the odor.
-Don't smoke or strike any matches.
-Don’t light any candles.
-Don't flip light switches on or off.
-Don't use a telephone.
-Don’t use any electrical equipment or lights that
might create a spark in the area of the odor.
-Don’t use the doorbell.
-Don’t adjust thermostats or appliance controls.
-Don’t use elevators.
-Put out all open flames.
Your tank gauge is a percentage of the liquid amount in your tank.
Example: If your have a 250 Gallon Propane Tank, and your gauge reads 60%. You have about 150 gallons. 250g x .60 = 150
Below is a PDF Document link to a propane safety booklet.