4 Acoustic Noise and its Measurement
Noise level meters, unless very cheap, have primarily two settings, giving readings in dBA and LIN (or dBC).
dBA or dB(A) – either seems currently acceptable in the UK. This is a measurement which gives a reasonable approximation to loudness as perceived by the average person. The ‘A’ weighting network gives the measuring instrument a response which allows for the ear’s lack of sensitivity to low frequencies. See Figure 10.
dB(C). Some noise level meters, particularly in the USA, have a setting marked ‘C’. (Older meters may have a ‘B’ setting. This ...