Automated measurement of noise violations in the therapeutic workplace.

The present analysis was conducted to validate an automated measurement system of noise violations by participants in the therapeutic workplace, which is a model workplace that offers paid employment and vocational training programs to illicit drug users. We collected data on dB levels via an electronic dB meter in a computer classroom with many different sound sources, and defined noise violations as sounds exceeding 55 dB. Human observers recorded whether staff or participants were responsible for violations, the types of events that resulted in violations, and whether these events were a result of participant behavior. Our analyses revealed that participants caused the majority of noise violations. These results suggest that the automated measurement system collects valid data on participant behavior that contributes to noise violations. Our results also suggest that these behaviors can in principle be modified to reduce the frequency of noise violations. Suggestions for replication in other settings and interventions designed to reduce behaviors leading to noise violations involving feedback and incentives are discussed.