To produce a program that is compliant to the TWR Loudness Standard, there are different options.

But the first thing is to understand what Loudness-based measurement is and
leave Peak Normalizing behind!
There are some documents about it on the home page of this site.

Here is a (growing) list of possibilities:

TWR offers a free Loudness Analyser Portable (LAP) software.
If you want some audio samples with different Loudness to play with (measure and modify), download the Audio Samples package here.

A very efficient batch processing tool for setting the correct Loudness in your productions:

Here is a very good video from a guy called Jason on how to use Loudness in Adobe Audition CS6

More to come...