A glass of Scotch whiskey is often considered to be the height of good taste when it comes to alcoholic beverages. Business deals are sealed over the clink of glasses and lifetime friendships are formed. But just how much of a risk does whiskey present when it’s near an open flame? Should we really have a cigar with our next glass, or should we leave it for another occasion?
Bottled whiskey is typically provided at 80 proof (40% alcohol by volume) and while it can catch fire, it is not considered to be flammable. However, whiskey is flammable when it is at “cask strength” (52% to 66%) straight from the barrel.
Let’s take a look at what can make whisky flammable or not. Here’s what you need to know.
Also read: What Makes Something Flammable?
Table of Contents
What Is Whiskey? (Chemically)
Whiskey is one of the most complex hard liquors.
It is made in a seven-step process which includes preparation, mashing, fermenting, distilling, aging, and bottling.
It may involve malt and nearly any grain as the base quantity and additional compounds are added at different stages and may even leach out of the barrel when the whiskey is aging.
Thus, nobody can give you a concrete list of what, exactly, is in “whiskey” because every whiskey is different, and some are markedly different from all the others.
To make matters more complex, as we shall see in a little bit, there is also the conundrum of American “whiskeys” which are not whiskeys by the standard international definition and thus, are different again.
However, as a general rule, whiskey is alcohol and water as well as esters, aldehydes, whisky lactones, and phenolic compounds with other random compounds (mainly affecting flavor and odor) too.
This huge variance in chemical structure adds an extra note of challenge when it comes to answering questions about the flammability of whiskey.
The good news, however, is that because most of these chemicals exist in very small quantities – we can treat whiskey as a blend of ethanol and water and just ignore the rest.
Also read: Is Beer Flammable? Will it Catch Fire?
Does It Catch Fire?
Cask strength whiskey is flammable as it has a higher alcohol content, but regular bottled whiskey is usually not flammable, as it is diluted to a lower alcohol percentage.
If whiskey is in the cask – it is usually at a higher strength (52% to 66%) than it will be after bottling. Bottled whisky is either slightly diluted or mixed with other whiskies (a process known as “blending”) to change the overall alcohol percentage (usually around 40% ABV).
So, cask whiskey tends to burn very easily indeed, and once it is alight it may be hard for the flame to be extinguished. In fact, we’d suggest that if you are ever around casks of whiskey that are on fire, you should evacuate and hit the fire alarm and sprinkler activation on your way out of the door.
Bottle whiskey, on the other hand, tends to have a proof rating of about 80 which is 40% alcohol by volume.
Thus, it doesn’t burn very well. It can catch fire, but only briefly, because the water in the whiskey will quickly overwhelm any flame.
Take a look at this video for some alcohol flammability testing:
Is It A Flammable Liquid?
Whiskey is defined by shipping companies as a flammable liquid, but it is not technically flammable at bottle strength (80 proof).
Shipping companies consider all alcohol products, even beer, to be flammable.
However, from a chemical point of view – whiskey that is less than 100 proof (50% ABV), isn’t flammable, though it is combustible.
The self-extinguishing nature of whiskeys with a higher water content means they just won’t burn.
Also read: Is Rum Flammable? Can it Catch on Fire?
Johnnie Walker Whiskey?
Jonnie Walker whiskey is not technically flammable. It may catch fire temporarily, but it will quickly go out due to low alcohol (40% ABV) and high water content.
However, as with Jameson there are many different versions of Johnnie Walker, which is the world’s best known and most popular whiskey brand, and some versions may be much stronger and are, indeed, flammable.
Also read: Is Methanol Flammable?
Most types of Bourbon are not flammable as the alcohol content is around 40% ABV.
Bourbon and other American whiskies including Jack Daniels, Rye, Millet, etc. are not technically “whiskey” in the same way as Scotch, Irish or even Japanese whiskies.
However, they too contain alcohol and are thus, considered “flammable”, though once again – the majority of these whiskies will be at 80 proof (or even less) and won’t be capable of carrying a flame for any length of time.
Most types of Jameson Whiskey, like most bottled whiskies, are not flammable. It may catch fire, but will not sustain a flame for long as the water content will extinguish itself.
Jameson is an Irish distiller and while, technically, all alcohol products can catch fire at the right temperature – the standard Jameson offering is only 80 proof.
And therefore, it can’t sustain a flame and isn’t “flammable” from the sense of “will it catch fire and cause harm?”
However, Jameson makes many different whiskeys and it is possible that their aged products (standard age for Jameson is 12-years-old) carry more alcohol and are, in fact, flammable.
What About 100 Proof Whiskey?
100 proof liquor (50% ABV) of any type including bourbon, rye, whiskey, millet, etc. is always considered to be flammable.
It is at this concentration (50% alcohol by volume) when the water in the drink is no longer capable of extinguishing the flame when the spirit catches fire.
Thus, if you ever order a round of flaming shots in a bar, the base spirit will always be one of 100 proof or more.
Also read: Is Ethanol Flammable? What You Should Know
Flashpoint Of Whiskey
The flashpoint of whiskey and most other spirits at 80 proof (40% ABV) is 79 degrees Fahrenheit (26 Celsius).
The flashpoint will depend on the strength (alcohol content) of the whiskey.
The flashpoint of ethanol (pure alcohol) is 61.9 degrees Fahrenheit (16.6 Celsius).