Muriatic acid is hydrogen chloride gas dissolved in water; many know it as hydrochloric acid. It is often used on masonry to etch the surface in preparation for paint or epoxy; etching degrades the surface so it is more receptive to the paint or epoxy. Use caution with using muriatic acid; it can cause permanent blindness if you get it in your eyes, and can severely burn your skin. Wear acid-resistant gloves, rubber boots, a long-sleeved shirt and pants, safety goggles and a respirator with an acid-grade filter. Keep a neutralizing agent handy with a garden hose and water at all times; and the outdoor area where you are working should be well-ventilated. Muriatic acid should not be used indoors.

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corrosive results of acid

Step 1

Tape an acid-resistant covering to the walls and trim around the floor, using painter's tape. Cover up to 12 inches up the wall.

Step 2

Cover adjacent plants or foliage with the acid-resistant covering to protect them from overspray.

Step 3

Mix a solution of muriatic acid and water, with 10 parts water and 1 part muriatic acid, in a bucket.

Step 4

Pour a puddle-sized amount of the muriatic acid solution on the floor. Scrub the area with a power scrubber. Use a bristle brush with a long handle to scrub areas adjacent to the wall and in corners that the power scrubber won't reach. Continue scrubbing the floor until you've covered the entire area.

Step 5

Spray water over the floor with a garden hose a few times to wash off the muriatic acid. Remove the pads from the power scrubber and rinse them off with the water. Rinse the bristle brush with water.

Step 6

Replace the clean pads on the power scrubber. Spray an area with water and scrub the area with the power scrubber. Scrub the entire floor with the scrubbers.

Step 7

Rinse the entire floor two more times with water to remove all the muriatic acid solution.