A vertical 120-gallon propane tank is 55 inches tall and 30 inches in diameter, while a horizontal 120-gallon tank is 24 inches in diameter and 66 inches long. To make room for growth, a 120-gallon tank holds 96 gallons of propane.
A vertical tank this size weighs 175 pounds when it is empty and 600 pounds when it is full. A 120-gallon horizontal tank weighs 300 pounds when it’s empty and 725 pounds when it’s full.
Appliances like water heaters, clothes dryers, space heaters, and kitchen ranges get their gas from these tanks. Usually, propane tanks are put next to a building, at least 10 feet away from any electric source that could start a fire.