Noise Dose is a measure of noise exposure similar to Lep’d, and is shown as a percentage (sometimes named Percentage Dose). It is dependant on exchange and criterion levels. In the UK, where the criterion level is the Upper Action Level of 85dBA, dose can best be described with the following statement:
100% Noise Dose = 85dBA for 8 hours
It is related to exposure time and Lep’d. The following tables give examples of dose levels using different changing factors, a criterion level of 90dBA is used throughout.
Each time the sound level increases by 3dB (the exchange rate), the dose doubles given the same exposure time. Similarly, if the sound level decreases by 3dB, it will halve for the same exposure time.
Doubling the exposure time doubles the dose and halving the exposure time halves the it, given the same sound level.