What is LAVG?
LAVG is simply the average sound level measured over the run time. This becomes a bit confusing when thresholds are used. Any sound below the threshold is not included in this average. Remember that sound is measured in logarithmic scale of decibels therefore the average cannot be computed by simply adding the levels and dividing by the number of samples. When averaging decibels, short durations of high levels can significantly contribute to the average level. Example: Assume the threshold is set to 80dB and the exchange rate is 5dB (the settings of OSHA’s Hearing Conservation Amendment). Consider taking a one-hour noise measurement in an office where the A-weighted sound level was typically between 50dB and 70dB. If the sound level never exceeded the 80dB threshold during the one hour period, then the LAVG would not indicate any reading at all. If 80dB was exceeded for only a few seconds due to a telephone ringing near the instrument, then only those seconds will contribute to the LAV
