20 lb Propane Tanks
The 20 pound tank is typically used for barbecue grills, camping and other cooking applications. This size tank holds 4.7 gallons of propane, and when full weighs around 40 pounds. Total BTU value for this size tank is 430,000 when full. This type of tank requires an OPD (overfill protection device).
This size tank, a 20 pound Cylinder, is available at many hardware stores and other retail outlets. Normally an exchange for an empty bottle is required or a deposit is charged for the new bottle.
Another variety of 20 pound tank is the Buffer Cylinder which is filled using a fixed level gauge or by weight. This tank also holds 4.7 gallons and has the same BTU of 430,000 when full but is typically used for indoor industrial work such as floor buffers or other maintenance machinery. Dimensions vary depending on the type and manufacturer. OPD is not required with this type of tank.