Floors commonly used in a clean room installation must be clean, not porous, suitable for periodic cleanling and disinfection and resistant to the operations and traffic to which they are submitted.
Therefore, and based on the requirements and characteristics of the area in which it is installed they can be made with different materials:

Epoxide resin floor:
The floor covering is continuous over the whole surface, applying a self-levelling resin mortar and epoxide binder.

PVC floor:
This floor consists of an antistatic PVC covering with 2-3 mm thickness, uninterrupted or with paving tiles usually 600 x 600 mm welded together. In both cases, the final features of the floor are the same.

Epoxide painted floor:
You can apply epoxide paint directly on a bottom previously treated and prepared.

There are other floors which are not so common, but also usable for certain types of installation: ininterrupted terrazzo, porcelain tiles etc.