Given the track of the signal FAST, it must be verified that, by lowering by 10 dB than the maximum value, the pulse duration is less than a second. Thus we see that it is necessary to simultaneously measure the temporal history with the three time constants IMPULSE, FAST and SLOW. However the only tool that allows a direct measurement of this type is the sound level of the Larson Davis and is very expensive. Most of the sound level meters instead allows a measurement time. So the only solution is to record the signal and then add it back into the sound level meter in methodology IMPULSE, FAST and SLOW.