And don't tip the remains down the sink/bath either when cleaning up, major blockage is possible....
We had a lad labouring for us briefly.. we had 10 bathrooms to tile @ 12m2 each and 1 kitchen backsplash & 4 Toilets @ 35m2 each ... It was made clear where to dispose of the waste gear and grout water by the Site foreman & Myself...
I got called back to the job 2 months later with the foreman and Contracts manager to determine what had blocked a filter system in the drains!!
On arrival the drive has been partially dug up and inspection covers were off...
Due to poor flow on the system (original piping having barely any fall) the waste from addy washouts & grout water residue being sat in the bottom of these pipes had gone stiff, so the drains were backing up!!
Never again... to this day we don't know how you can mistake a big metal yellow skip for a drain !