If you have ever tried to read a standards document you will know that it is hard work. Trying to separate the useful information from all the technical jargon can be very time consuming and even then you may not find the answer to your question. The bad news is, the Cabling Standards are no different, they are full of cross references, formulas and tables all of which can be a very daunting prospect and can make the installation engineer think twice about installing the stuff. Now for the good news, the standards are mostly concerned with the performance criteria of the components of a cabling system, and, as that is guaranteed by the manufacturers of the different cabling components, you don't have to worry about it. Please go to the Questions and Opinions page for my personal views on the subject.
Lets work on a hypothetical installation.
It is for 30 double outlets, in one building, with an average run of about 30m. Each double outlet will be used for one PC and one telephone. 3 x 32 way RJ45 patch panels. 6 x boxes of Cat 5e cable. 30 x 1.5m patch leads 30 x 2m patch leads 30 x 3m fly leads.