Vusal,
How it was explained to me.
When it comes to sprinklers NFPA #13 is a standard and the standard assumes fire sprinkler are everywhere in a building, except where specifically addressed otherwise, regardless of building size.
According to NFPA #13 if you have a small 100 sq ft rubber tire warehouse it is to have sprinklers.
It is not the standards that tell us in what buildings fire sprinklers need to be installed that is the job of the Building Code. The Building Code is law while NFPA #13 is simply a standard that tells you how to do something when it is required but the standard does not say anything about where it is required by law.
NFPA does have a building code but it has to be adopted by law to be enforceable.