Noise Pollution Level
There are a number of different noise criteria measurements used by local authorities to determine noise levels in the community.
Noise Pollution Level, LNP, takes into account two basic attributes of noise annoyance: the higher the level of noise, the greater the disturbance and the larger the variability of fluctuations in level, the more annoying it becomes. A variation of LAeqT which accounts for short-term variability in noise level.
For a gaussian distribution of dB(A) level, it is defined as: