Peracetic acid is rather stable, just keep it out of light and store it in a cool place. Peracetic acid is commercially available, but SWiM never bought it since it is a small effort to make it SWihimself. Actually, SWiM didn't know it was sold in the kind of stores you mentioned.
MSD info... Mass Selective Detector info? SWiM doesn't think that MSDs like reactive peracids as peracetic acid that much... Try iodometric titration, has always been used to check the peracid concentration. Furthermore, if the peracetic acid concentration is 15%, it should show something else as well, don't you think?
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