The new EPA Guidance Note, NG4, is very welcome. The two previous guidance documents, NG1 and NG2 overlapped and this was the source of some confusion.
The new evening limit of 50 dB for the hours 19:00 to 23:00 is obviously going to cause some difficulties for plants running two or three shifts as typically noise levels may have been previously compliant and in the 50 dB to 55 dB range.
Reducing to 50 dB or below will take some doing. However, Noise Prediction Modelling can be very useful in identifying the sources of noise and the effect of noise control measures on noise levels at the boundary. Modelling can identify the noisy equipment for which abatement will be most cost effective. We have had particular success recently with large saw mills and the post abatement noise levels have been very close to those predicted.
If you think that the new limits will cause you a noise problem, then we would be happy to talk you through the options.