Three bucket system for area cleaning

Sir,

Industry practice for floor cleaning is 3 bucket system; one for Disinfectant, WFI and empty bucket.

Procedure: Mop the floor with WFI and squeeze in empty bucket, again with disinfectant mop the floor and rinse the mop with WFI, Repeat the procedure.

But if we dip the mop in WFI again and again and dipping in disinfectant will cause diluting the actual concentration of disinfectant.

Why do not we use one more same disinfectant instead of WFI for cleaning?? We mop the floor with disinfectant(1) squeeze in empty bucket and dip in second disinfectant anf mop the floor for disinfection.

What is the right practice??? Please confirm?