Does Gasoline Go Bad?

gasoline containment
Gasoline, like other forms of fuel, is often stored above ground in gigantic metal containers. Refineries all over the world have these large contraptions regularly inspected for structural integrity. For this, they call upon inspection services to do an API 653 inspection, which involves a thorough assessment of the safety of a tank’s structural components. Such an inspection is a given—gasoline, after all, is a highly volatile substance.

But for the sake of curiosity, assume that gasoline isn’t stored in such a rigorously constructed container. Stored out in the open and exposed to the elements, will it go bad? Science says it will. There’s obviously a good reason that sealed containers are always recommended for storing gasoline, apart from it being a fire hazard.

Why Gasoline Goes Bad

Gasoline is a highly refined product. This means that it’s brewed to have certain characteristics — in this case, it’s made to easily vaporize for efficient burning inside an engine. Also known as volatility, this property of gasoline also renders it perishable. All the volatile substances in gasoline can easily evaporate if the fuel is stored in open air. As a result, gasoline’s ability to burn degrades. It goes bad, as colloquial terms put it.

Not a lot of people are aware of this fact, even those who work in popular media. For instance, creators of science fiction (whether in novels or video games) almost always portray gasoline and other fuels as an incorruptible resource. It isn’t. Unless laced with a chemical stabilizer, gasoline will degrade during storage. Perhaps it’s time that several creators of post-apocalyptic fiction correct this.

Another thing that degrades gasoline over time is its octane quality. This is due to a process called oxidation. Over time, gasoline’s combustible content would just evaporate into thin air if it has even the smallest way out of a tank or any other container. Aside from physical “symptoms” like a darkened color and a sour smell, old gas is obviously less potent than a newer batch.

If refineries regularly check their storage tanks for structural defects, it’s because of gasoline’s highly volatile nature. Such a move isn’t just industry-standard — it’s logical.