They aren't too noisy in other states because the other states don't have as stringent noise limits. You could argue that the other states are behind, and should catch up with NSW.
My comments have been in continuation of
If this country is trying to run a "national" rail system then how come a Aurizon 2800 class can run in Victoria and SA, but not NSW.
I would have thought in 2013 we would have national polices and procedures.
It is ludicrous to disallow something in one state that is allowed in another or vice versa.