How To Clean A Garage Floor With Muriatic Acid?

Concrete garage floors can get awfully dirty and oil stained. What can you do to remove deep, stubborn stains? One product that is often recommended is Muriatic acid, and this is a very effective way to remove stains of all sorts. Unfortunately, it can also be an effective way to etch, soften and remove a bit of your garage floor, as well.

Acidic cleaners, such as Muriatic acid can pull the calcium hydroxide out of a hardened concrete floor. This causes efflorescence (a dusty, white material) to form on the surface of the concrete. When this happens, you must take steps to remove it.

Even with this potential for damage, and the fact that Muriatic acid is rather dangerous to deal with (!), it can be the product of choice as a last resort when dealing with very stubborn concrete garage floor stains. In this article, we present advice and tips to help you use Muriatic acid safely and effectively. Read on to learn more.

9 Steps To Clean A Garage Floor With Muriatic Acid

Steps To Clean A Garage Floor With Muriatic Acid
  1. Sweep the floor and clear away any items that would be damaged by acid.
  2. Mop the floor or hose it down and allow it to become almost dry.
  3. Wear acid resistant rubber gloves, face covering, eye protection and a respirator.
  4. Gently pour 1 part Muriatic acid into 10 parts water in a heavy duty plastic container.
  5. Slowly and carefully pour the diluted Muriatic acid directly onto the stained area.
  6. Use a nylon bristle scrub brush or push broom to rub it in.
  7. Let the acid stand on the stained surface for several seconds or as per label instructions.
  8. Sprinkle baking soda over the treated area and allow it to stand for a few minutes to neutralize the acid.
  9. Use a pressure washer set at 1200 PSI or greater to thoroughly rinse the neutralized acid away.

Note that it is very important to protect your nasal passages, skin and eyes from the acid and to neutralize it before washing it away. If you spray it away without neutralizing it, you may end up with damage to your surrounding floor and/or belongings.

You might also be injured by acidic splash-back if the acid is not neutralized.

In this video, we see that when the presenter uses Muriatic acid to remove oil stains from his driveway, it does a good job of removing the oil, but it leaves the surface of the drive a bit degraded and pockmarked.

Driveway Oil Stain Removal Muriatic Acid

Treatment For Hydrogen Chloride Burns

If you do splash Muriatic acid onto your skin, flush the area with cool, running water for a solid ten minutes. Take off any clothing, jewelry or other item that has been touched by the acid and cover the burn with clean, dry gauze.

If the burn is large, deep, in a sensitive area or very painful, seek medical attention.

If you get Muriatic acid in your eyes, flush with water as directed above and call 911 for immediate medical attention.

It goes without saying that this acid is quite toxic when ingested or inhaled. Seek medical attention immediately in the case of ingestion or significant inhalation.

11 Tips For Safe Usage Of Muriatic Acid

11 Tips For Safe Usage Of Muriatic Acid
  1. Assemble everything you need in advance. Acid works fast, and you don’t want to have to scramble around looking for things while it eats away your garage floor.
  2. If your garage floor is very dirty, give it a good scrubbing with a commercial degreaser before applying Muriatic acid.
  3. After washing your garage floor, be sure to allow it to become nearly dry before applying Muriatic acid. Too much moisture on the floor will dilute the chemical, and it will enable the chemical to run into areas you don’t want affected.
    4.Keep baking soda (or garden lime) close at hand at all times to neutralize spills.
  4. A quart spray bottle of water with a half cup of baking soda dissolved in it is also useful.
    Never use full strength Muriatic acid. Dilute it with ten parts water to one part acid. Always pour the acid very gently into the water, not vice-versa.
  5. Do not mix muriatic acid with any other acid or chemical.
  6. Use a heavy duty plastic watering can to mix the acid and water and to pour it gently onto the stain. It’s a good idea to have a couple of watering cans in case the first one becomes damaged by the acid. The plastic should be able to withstand the acid for an hour, so if you work quickly and efficiently, you shouldn’t have a problem.
  7. The scrub brush or broom you use should have nylon bristles, or it should otherwise be specially made for use with acid. As with the watering can, it’s a good idea to have a spare on hand, just in case the first one dissolves.
  8. Some instructions say to leave the acid in place for as long as ten minutes. Don’t start out with this. Begin by allowing it to sit for a few seconds. This may do the trick. You can always do a second treatment if needed, but you cannot undo damage caused by leaving acid on your garage floor for too long.
  9. If you get acid on your skin, flush it with copious amounts of water immediately. Keep your garden hose close at hand and turned on. You can use a nozzle sprayer to avoid having water pouring out onto the ground as you work.
  10. Work slowly, carefully and incrementally the whole time. You want to be in complete control of the acid with no accidental splashing or running.

Follow Safe Storage And Disposal Practices

Store Muriatic acid outside, away from direct sunlight and safely out of the reach of children and animals, in the container in which it came. These containers have specially vented caps.

Muriatic acid does not freeze, and if you store it indoors, the fumes venting from the container may damage surrounding surfaces and items. If you put the acid into another container, it will damage or destroy the container.

Always dispose of Muriatic acid correctly. This is a dangerous chemical. Never pour it down the drain or otherwise allow it to come in contact with any waterway. Contact your city and/or your local recycling organization for instructions on properly disposing of Muriatic acid in your location.



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