Like others mentioned, I'd make sure to have an SOP for operating it. Last time I had one of these, we just updated our forklift training program to include instructions on the floor scrubber, trained all equipment operators to the same standard. Covers the operation of the machine from the OSHA standpoint.
Possible blind spot would be ensuring the person operating it has your training for mixing chemicals. Lots of warehouse forklift operators don't have chemical training beyond where to find the SDS for a spill, but whomever runs the floor scrubber needs to show training for mixing chemicals and disposal of the waste water.
Lastly, floor scrubbers are notoriously dirty and will absolutely draw attention from your GFSI auditors. You'll want to add contact points from it to your environmental monitoring program for listeria to be able to prove it's not a source or cause of spread within your facility. Likewise, make sure it's added to your master sanitation schedule with detailed instructions on how to break it down for cleaning.