How to get rust out of concrete

Blot first, then test white vinegar with salt on the concrete; rust can be stubborn and may need a commercial product made for this, used per its label.

Blot any wet area with clean cloths; do not rub.
Test white vinegar on a small hidden area of the concrete and let it dry.
If the test area looks unchanged, cover the rust stain with white vinegar and sprinkle salt over it.
Blot the stain with clean cloths, lifting what loosens.
Use a soft brush lightly if the stain is not lifting; do not scrub hard.
Rinse with cool water and blot dry.
Repeat once if the stain is lighter.

Don't do this

Do not rub, because rubbing can push the stain into the concrete.
Do not skip the white vinegar test, because some concrete can change in appearance.
Do not use white vinegar if the test area changes, because it may mark the concrete.
Do not scrub hard with a soft brush, because that can affect the surface.

Old rust on concrete can be difficult to remove. Use a commercial product made for this, used per its label.

Grounded in: site.extension.uga.edu. Every step follows sentences verified verbatim on those pages.

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