The topic of this paper is limited to industrial floors, more specifically, floors in underground spaces, which are used as parking areas in residential or office buildings. The question is whether this division is still valid, but that is not essential for the issues addressed in this paper. Of course, all these questions will need to be addressed with both the construction companies and the suppliers of materials. I would be also useful to also know the opinion of designers. The purpose of my paper is, therefore, to generate debate about these topics and allow for further improvement of CSN 74 4505 and, eventually, to create special technical conditions.