Does Kerosene Go Bad? How Long Does It Last?

Kerosene is a popular fuel source still used in many households around the world, and commonly used for heating, lighting, and cooking. Although nowhere near as popular in the US as it used to be, it is still a viable fuel for many homes.

However, if you rely on stored kerosene for an extended period of time, you may be wondering if it ever expires. And if so, how long can you store it before it goes bad?

Kerosene has a shelf life of typically 2-6 years before it needs to be replaced. This is because the liquid can degrade over time with exposure to oxygen or moisture, and eventually it can become contaminated or even hazardous due to mold growth in the container.

Compared to some other hydrocarbon fuels, this is a pretty good shelf life, but not so long that you can rely on it for decades as you would with propane.

If you have kerosene heating in your home, or other kerosene-fueled appliances, you’ll need to know more to make the most of it.

Keep reading and I will tell you all about kerosene’s shelf life…

What is Kerosene, Exactly?

Kerosene is a type of refined petroleum oil that is commonly used as a fuel source for heating and other appliances.

It’s obtained from the fractional distillation of crude oil and typically has a clear or a faint, pale yellow color, though it should always be clear. We’ll talk more about that in a moment.

Kerosene has a wide range of other applications though, including lighting, cooking, and even as a jet engine fuel. It’s relatively high flashpoint, makes it somewhat safer to handle than other fuels such as gasoline.

Understanding Kerosene Degradation

Like any other fuel, kerosene can and will degrade over time. Overtime, air and condensation cause kerosene to break down into various compounds, including peroxides, acids, and gums.

This degradation process can lead to a decrease in the quality of the fuel and can ultimately make it unusable. But far and away the most significant factor that contributes to kerosene degradation is exposure to moisture.

Condensation is the enemy! Water will dilute kerosene and often lead to the formation of mold or “sludge” which will quite literally colonize the fuel and make it unusable by breaking it down.

Fascinating but gross, and terrible if it happens to your fuel!

Do Different Kinds of Kerosene Have Different Shelf Lives?

Yes. The shelf life of kerosene can vary depending on the specific type being used. Aviation kerosene, for example, is often treated with special additives to increase its shelf life and improve its performance.

These additives can help to prevent oxidation and degradation, which can also extend the life of the fuel…

However, other types of kerosene, such as common heating kerosene or “lamp” oil, may not have these additives and accordingly may have a much shorter shelf life.

Additionally, kerosene that has been blended with biofuels or other additives may also have a different shelf life than pure kerosene, usually shorter since they have a tendency to separate.

How Can You Identify Expired Kerosene?

You sure can. Identifying expired kerosene isn’t too challenging, but there are usually a few telltale signs to watch out for.

The first thing you may notice is a change in color, as expired kerosene will typically appear a darker yellow color or have a cloudy or milky look compared to fresh kerosene.

Bad or questionable kerosene may also smell bad. You could detect an odor that is distinctly “off” or different from fresh kerosene.

Also, any obvious chunks, layers, film or other “slime” or “sludge” in the kerosene is an obvious sign that is contaminated by mold or other harmful microorganisms.

What are Some Ways to Extend the Shelf Life of Kerosene?

There are a few strategies you can use to extend the shelf life of kerosene. One way is to store the kerosene in a cool, dry place away from direct sunlight.

Exposure to heat and sunlight can accelerate the degradation process and promote condensation, a double whammy, so storing the fuel in a dark, cool space can help to slow down this process.

It’s also essential to keep the kerosene container tightly sealed to prevent outside moisture and air from entering and contaminating the fuel that way.

Can You Test Old Kerosene for Usability?

Yes. One way to check the quality of kerosene is to use a test kit that measures the fuel’s acidity level. If the acidity level is too high, it may indicate that the fuel has degraded and may not be suitable for use.

Another way is to perform a visual inspection of the kerosene as described above, looking for any obvious signs of cloudiness, foreign matter, or discoloration. These can be indications that the fuel is too far gone and should be disposed of properly.

Lastly, you can always test it by burning it: if it doesn’t burn correctly and evenly or if produces any notably unpleasant or just different odors, you’ll know it’s degraded and possibly compromised.

Is it Safe to Burn Expired Kerosene?

For truly expired, nasty kerosene, no, it’s not safe. When kerosene degrades past the point of usability, it can form harmful compounds that can be released during combustion.

Bad kerosene is also highly likely to malfunction or even cause damage to your heater, lamp or other appliance.

Using expired kerosene can also pose a safety risk, as it will be more unpredictable than fresh stuff and increase the likelihood of accident when you inevitably have to attempt to drain it from whatever you put it in.

Ultimately, it’s best to dispose of expired kerosene properly and replace it with fresh fuel to avoid any potential safety hazards.

But, if you just have kerosene that is a bit old or slightly off, you can usually use it safely as long as you expect a slight decline in performance.

What Can You Do with Expired Kerosene?

Expired kerosene is not good for much. There are only a few ways to dispose of expired kerosene safely and responsibly.

The best option is to contact a hazardous waste disposal company, who can safely handle and dispose of the fuel, or else bring it to your local hazardous waste collection day.

Some cities and municipalities also offer hazardous waste collection programs, where you can drop off expired kerosene and other hazardous materials for safe disposal at no or little cost.

If you only have a small amount of older (non-cloudy/slimy) kerosene, you can mix it with fresh kerosene to dilute the expired fuel and use it normally, burning it off.

This can help to minimize any potential issues with disposing of the fuel while allowing you to use it up. Note that mixing expired and fresh kerosene can impact the quality and performance of the fuel as mentioned previously.

One thing you should never, ever do is pour expired kerosene down the drain or dispose of it in the trash with your other garbage. This can lead to serious waterway pollution and other environmental damage.