What is the Criterion Level?

• A. The trade-off between noise level and exposure duration
• B. The sound level allowed for an 8-hour exposure, used as the basis for measurement of a noise standard
• C. A survey to classify noise sources
• D. The Wet Bulb Globe Temperature index

Answer: (B)

The criterion level is the reference sound level used to define the permissible exposure for an eight-hour work shift. It serves as the baseline against which measured noise levels are evaluated, so dosimetry can determine how long a worker can be exposed before reaching the standard. The exact dB value depends on the regulation being used, but the idea is that this level sets the 8-hour exposure standard that measurement and dose calculations reference. It isn’t describing the trade-off between level and duration (that’s handled by the exchange rate), nor a survey of noise sources, nor a heat stress index like Wet Bulb Globe Temperature.