Where are porous or rough materials not allowed?

Porous or rough materials are not allowed in restrooms and refrigeration primarily due to their ability to harbor bacteria and other pathogens. In environments where cleanliness and sanitation are critical, such as restrooms and areas where food is stored or prepared, smooth and non-porous materials are preferred. These materials can be easily cleaned and disinfected, reducing the risk of contamination.

In the context of refrigeration, using porous materials could lead to the absorption of moisture and food particles, which could foster bacterial growth and compromise food safety. Similarly, in restrooms, surfaces need to be easily maintained to prevent the buildup of germs and odors that could pose health risks. This requirement ensures that both food safety and public health standards are upheld in those specific environments.