In Sweden, the minimum impact sound insulation requirements in dwellings is LnT,w + CI,50-2500 = 56 dB. Something worth noting about the spectrum adaptation term is that it is just a logarithmic addition of the 1/3 octave bands 50-2500 Hz. This is somewhat misleading because the way it is written it looks as if one should first calculate LnT,w, then the spectrum adaptation term and finally add them. It might have been more pedagogic to call it LnT,w,50 or something similar, which they are called now in the Swedish standard, by the way.