Keeping a strong cleaning agent like muriatic acid in a corner of your house comes in handy while cleaning your pool or basement. But many acids are flammable and you might want to know if your cleaning agent is a fire hazard. So, is muriatic acid flammable?
No, muriatic acid isn’t flammable or combustible as it’s an inorganic acid. However, while reacting with other substances, it can produce hazardous gases and chemicals. For example, muriatic acid can react with metals and produce flammable and explosive hydrogen gas.
Apart from that, liquid muriatic acid and its fumes are dangerous for your skin and eyes. If you want to learn more about the flammability of muriatic acid and how to protect yourself from its negative effects, keep reading!

Understanding Flammability
In simple words, the flammability of a substance indicates how easily the substance can burn. It’s the chemical properties of a substance that makes it flammable or non-flammable.
Besides, environmental factors like high temperature and moisture affect the flammability of a material. Gasoline, wood, fabric, organic acid are some flammable materials that ignite or burn upon catching fire.
Metal, brick masonry, nitrogen gas, concrete blocks, inorganic acids, etc., are some non-flammable products which fire can’t ignite.
Why Muriatic Acid is Not Flammable?
The chemical composition of muriatic acid makes it non-flammable. Muriatic acid present in regular cleaning products mainly contains 31.5% hydrogen chloride gas dissolved in water.
Typically, the ratio of hydrochloride acid and water in muriatic acid solution is 1:10. It also contains other impurities such as iron and plastic.
However, you must check the label on the product before using it. Neither hydrochloric acid nor water is flammable which makes the muriatic acid non-flammable as well.
It’s an inorganic acid which doesn’t contain any hydrocarbon chain that facilitates the burning process. As a result, muriatic acid doesn’t burn in any form, be it liquid or gas.
Chemical and Physical Properties of Muriatic Acid

If you’re planning to purchase a product that contains muriatic acid, you must learn its properties first. There are many ways it can harm your body if you’re not careful.
So, here are some notable properties of muriatic acid-
High Reactivity
Since muriatic acid is a diluted form of a very strong acid (hydrochloric acid), it’s highly reactive with most materials including iron, steel, and aluminum. In fact, it’s considered one of the most hazardous acids that react and damage almost everything except for a few plastic types.
Muriatic acid easily reacts with different metals (aluminum, magnesium) and bases (sodium hydroxide). While reacting, it produces a high amount of heat.
Corrosiveness
From the strongest metal to regular clothing, muriatic acid can dissolve it all.
So, in regular cleaning products, the acid is diluted with water to prevent it from corroding the surface material you’ll be cleaning.
However, even diluted muriatic acid can be corrosive to the skin. So, you must take proper caution before using it.
Pungent Odor
One identifying property of muriatic acid is its annoying pungent odor. As mentioned, muriatic acid contains some impurities which give it a yellowish tint and a pungent odor.
The sharp smell of muriatic acid can make you uncomfortable and irritate your nose.
Non-Flammable
Thankfully, muriatic acid won’t burn upon coming in contact with a flame. You can freely use and store them in your house without worrying about accidentally catching fire.
Just be careful while applying it to any type of metal as it will react and produce flammable hydrogen gas. Be sure to check the label first to see if the acid can be used on metals.
Chemical Reaction Between Muriatic Acid and Other Materials
The high reactivity of muriatic acid makes it very useful for household and industrial uses. It’s often used for producing steel, removing mineral deposits, producing organic and inorganic compounds, etc.
Below are the chemical reactions of muriatic acid with other materials and how it’s used in industrial production.
Reaction with Steel
Muriatic acid is used during the pickling of steel. The acid is used to remove rust from the metal surface.

Here, 18% muriatic acid reacts with the iron atoms of rust. Muriatic acid dissolves rust and other impurities from the surface.
Reactions While Removing Mineral Deposits
Too often, your pools, bathroom faucets, water lines, and even unused tiles might be stained by mineral deposits. This is caused by compounds containing calcium or lime.
Muriatic acid reacts with calcium, magnesium, or other minerals and easily dissolves them. After that, you can easily wipe off the mineral deposits with a damp cloth.
Producing Organic and Inorganic Compounds
In industries, muriatic acid is used as a reagent to produce organic compounds like dichloroethane and vinyl chloride. Muriatic acid goes through a chain of reactions to produce bisphenol A.
Similarly, the acid can also react with various substances to produce polyaluminum chloride and iron chloride. All these organic and inorganic chemicals have various applications such as PVC plastic production, water treatment, and galvanizing metals.
Safety Measures for Using Muriatic Acid
If you’re using muriatic acid cleaning solution, you must follow some safety measures to protect yourself from its effects. Here’s what you need to do —
Wear Protective Gloves
Even though muriatic acid contains only 31.5% hydrochloride acid, it’s still corrosive to the skin.
So, you must wear gloves before using the acid. A pair of rubber gloves will be enough to avoid direct contact with muriatic acid.
Wear Goggles
As you know, muriatic acid has a very strong pungent smell. If the acid fume gets into your nostrils, it can irritate your nose, throat, and lungs. Besides, the acid fume can irritate your eyes as well.
To avoid this, you need to wear a gas mask that properly covers your mouth, nostrils, and eyes.
Ventilation Is Important
While working with muriatic acid, you’ll be exposed to toxic acidic fumes. If you work in a closed room without proper air, the fume will get trapped.
Therefore, you must work in a well-ventilated area so that the fume can quickly pass through.
Proper Storage
It’s best if you can store muriatic acid outdoors in a plastic or wooden box near your pool or inside a shed. The toxic fume of acid gets trapped in a closed area and makes the air toxic.
Also, the fume can react with the metal structures of your house and rust them over time. Hence, if you want to store muriatic acid indoors, keep it in a well-ventilated area far from any metal.
Follow Label Instructions
Always check out the label on the muriatic acid container before using it. If there’s any special safety instructions, be sure to follow them.
Moreover, it should tell you the proper ways of using the acid and which surfaces you should avoid applying the acid on.
Wrapping Up!
In this write-up, we provided a detailed answer to ‘is muriatic acid flammable?’ Muriatic acid used in cleaning products is mild, non-flammable, and less corrosive. Although it doesn’t possess any fire threat, the acid is harmful to the human body.
So, you must wear gloves and a gas mask while working with the chemical to avoid unpleasant circumstances.