Rinsing oxalic acid

[petemoss]

I have been considering applying oxalic acid to driveways after I clean them, as a brightener. I was wondering, if I do this, will I have to rinse it off after a certain dwell time, or could I leave it on the driveway. I was mainly concerened wether it would pose any health problems to pets and such if not rinsed off.

Thanks

 

[Tim Smith]

I do not rinse on my commercial accounts - it really whitens the concrete, but I do on residential sometimes.