The Importance Of The 80/20 Fill Rule


80/20 rule propane new jerseyIf you’ve ever checked your aboveground propane tank gauge after a propane delivery from Blue Flame to your southern New Jersey home and wondered why the gauge reads that your tank is only 80 percent full, there’s a simple answer: Science and safety.

Propane And Temperature

Propane is like water in that it expands in the heat, only a lot more so than water. Over the same increase in temperature, the volume of propane increases around 17 times over the volume of water.

With that expansion, your propane tank needs room to allow for it. That’s where the 80/20 rule for propane safety comes in. If you have a 500 gallon propane tank, it can only be filled to 400 gallons, or 80 percent of the tank. That 20 percent of empty space in your tank is the room for expansion of propane gas.

Propane safety is why your Blue Flame propane delivery driver will not fill your aboveground propane tank more than 80 percent full.

Underground propane tanks can be filled slightly more than 80 percent since being underground insulates the tanks more from the heat.

Sometimes, you may see fluctuation in your propane tank gauge levels, especially when there are fast temperature swings from a hot day to a cool night. Don’t worry, it’s a normal occurrence. What’s happening is that the density of the propane in your tank is adjusting as the temperature changes. The amount of propane in your tank hasn’t changed. It’s just either taking up more room as it expands, or going back down to its normal size.

Propane tank painting – How it can effect levels

One more propane safety note: NEVER paint your propane tank a dark color. Propane tanks are light for a reason. Lighter shades like white or beige reflect the outside heat. Darker colors absorb the heat, which creates dangerous levels of propane gas expansion.

Tired of always walking out to the tank to check your propane tank level? Sign up for our automatic delivery program and we’ll track how much propane you’ll use, and schedule a propane delivery before your propane tank runs low. We can also track your actual propane usage with wireless tank monitoring!

Trust the Blue Flame professionals for safe and reliable propane delivery to your southern New Jersey home. Contact us today to schedule a propane delivery or to find out about our automatic propane delivery!