Propane is a gas—and you’re probably aware of that. However, you may wonder why your tank is so heavy when you get it filled up. And why is it measured in gallons?
Knowing about what’s in your propane tank—whether it’s a portable cylinder you use to fire up your grill, or a residential-size propane storage tank that fuels your heating systems and other appliances—can help you use it safely and effectively.
For starters, you may not know that the propane in your tank is stored as a liquid. This is an important distinction because while it comes out of the tank as gas, it’s stored in liquid form. Visually, it looks a lot like water. Propane is stored as a liquid because, in its gaseous state, it takes up 270 times more space than liquid propane. Imagine having a tank that big to store propane for your grill—let alone your house!
Because it’s stored as a liquid in your tank, it’s measured in gallons—except for portable cylinders, which are usually measured by weight in pounds.
If propane is stored as a liquid in your tank, how does it turn back into a gas? Believe it or not, it boils—just like boiling water turns into a gas (steam). Unlike water, which boils at 212 F, propane boils as soon as the temperature is -44F or higher. In its liquid form, it’s extremely cold, but because it turns to gas instantly when exposed to even winter temps as low as zero, propane spills are harmless.
When you open the valve on your tank, the pressure in the tank drops and the propane inside is exposed to outside temperatures and begins to boil. From that point, it turns to gas and moves through the gas lines to fuel your heating systems, cooking appliances, and other equipment.
Maintaining the pressure when the valves are closed is important. That’s why we need to perform pressure tests after a runout. If the pressure changes in the lines—as happens when you run out of fuel—there is the possibility that the joint compound sealing connections could contract and create a leak. While propane is completely safe under most conditions, it can be highly flammable, so leaking propane lines can be dangerous. The best way to avoid runouts is to sign up for our tank monitoring services.
Propane has a distinct rotten-egg smell to help you quickly notice leaking gas. In its gaseous form, it can be flammable. Make sure everyone in your home can recognize the odor. If you do smell gas:
At Depew, safety is our number one priority. All our technicians follow the highest safety standards for all your propane deliveries, and we invest in ongoing training to keep them up to date in the latest technologies and safety protocols available.
You can find links to more propane safety information on our propane safety page. These will help you get familiar with propane best practices and other tips.
And as always, we’re here to help with everything from convenient automatic deliveries to answers to any of your questions—contact us today.