What You Need To Know About The 80/20 Rule For Propane Tanks

Few things are more maddening than buying something at the store and realizing that the box, bag, or other container is only partially full. (Depending on if you’re a pessimist or an optimist, you may say it’s partially empty.) Regardless, the excuse is always “Contents may settle during shipping…” Okay, you tell yourself, so be it.

What about your propane tank? Were you aware that it’s only 80% full when you purchase it? Yes, that means 20% empty. But it’s got nothing to do with settling or the dealer trying to rip you off. No, the 80/20 rule for propane tanks has far more to do with safety and science than anything else.

The Science of Propane

You may know that water expands in heat. So does liquid propane. But it’s got water beat by a long shot! When both are subjected to the exact same high temperature, propane expands approximately 17 times more!

That liquid propane needs somewhere to go when expansion happens. That’s why your propane tank is 20% empty on top. It is a “safety expansion” area provided for the propane.

“The Rule of Propane Safety – 80/20”

Yes, it’s a real thing. As an example, your tank can only be filled to 400 gallons even if it’s a 500 gallon tank – obviously, that’s a big tank. But that’s not unheard of when you’re talking about underground propane tanks. Although, with underground tanks, the 80% may be exceeded slightly because the tanks are insulated from temperature fluctuations and heat by the ground around them.

What else can temperature changes do? You may notice the gauge on your propane tank fluctuating during temperature changes. It’s okay – that’s normal. The amount of propane held within has not altered, but merely expanded. The gauge level will go down when the temperature goes down.

The Color of Propane Tanks

Have you ever wondered why propane tanks are painted with something light in color (light gray, white, etc.)? There is a reason. Darker colors absorb heat. Lighter colors reflect outside heat. Dangerous levels of expansion could be reached if the propane tank absorbed enough heat to become hazardous. You may not be crazy about the color, but never, ever paint your propane tank in a dark color!

In direct relation to the 80/20 rule, propane tanks should always be stored and transported in an upright position. This allows the safety expansion area to remain at the safety release valve, where it belongs. If the safety release valve is triggered, only vapor will be released – not liquid propane. If liquid propane is released, and an ignition source is present, that could spell disaster.

Do you transport propane tanks on a regular basis? Are propane tanks part of necessary equipment relating to your business or favorite pastime? Regardless, Mickey Genuine Parts has what you need for the proper transportation of full or empty propane tanks. We have an impressive inventory of parts, accessories, and more.

If you would like additional information about our propane gas transportation equipment, or if you’d like to make an appointment at one of our certified service centers throughout the United States, contact one of our knowledgeable representatives today.

Let’s keep truckin'.

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