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Other countries may use different Criterion levels and Exchange Rate values for
their legislation.
The Threshold is the sound level at below which the Dose is not accumulated.
The threshold level is determined by ( Criterion – Selected Threshold value).
Therefore if the criterion is 85 and the selected threshold value is -10 then
Dose is only accumulated from noise levels greater than 85 - 10 or 75 decibels.
In the UK, the Control of Noise at Work Regulations requires a threshold of
-10dB (75dB).
An example screen display may be: -
Noise Dose per Hour
This is more commonly known as Dose per Hour and is expressed as a
percentage.
The Dose per Hour is the Dose value that the employee would be subject to for
each hour of the working shift.
As an example, if a continuous noise level of 85dB is being subject to an
employee then the Dose per Hour would be 100 / 8 = 12.5%
An example screen display may be: -
Pascal Squared Hours
This is more commonly known as Pa
2
Hr and is another alternative method to
show how much noise exposure an employee has been exposed to.
If an employee has been exposed to a continual noise level of 85dB for an 8 hour
working shift then the employee will have been subject to 1 Pa
2
Hr.
An example screen display may be: -
Do% 59.4
Hr% 23.2
P2h 0.4
