You should consider specifying floors with good slip resistance in the wet. In bathrooms, the floor will need to be suitable for both shod and barefoot users.
However, smooth shiny floors, with very little slip resistance, are commonly specified for these areas. It may be difficult for end users to control the risk of slips, if this type of floor is fitted.
Slip resistant floors will only retain their properties if they are cleaned according to manufacturers' instructions. It is important that you ensure you provide this information.
Consider the information on test methods in the flooring module, before selecting slip resistant flooring.