hi there
just dnt use bleach,
it is classed as a hazardous chemical in the workplace,
example
yu clean domestic toilet with bleach, but dont wash it all away, then the client adds another toilet cleaner for some reason, resultant gas affects you client
or
you clean a toilet with a toilet cleaner, and then the client putws bleach down the toilet, again gas can be formed,
in either event the consequences are not good, just avoid it
regards
martin