No matter what the chems or strength, you should always use the correct PPE because you just never know and accidents do happen.
I do not use the Oxalic here much because I have not had good luck with it on both rust and fertilizer stains. When I do try it out, I use the PPE to be safe because it is both an acid and a poison.
Always be safe.
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Superior Power Washing
Chris Chappell
Exterior House Cleaning in Corpus Christi Texas