This chapter introduces the impact of construction noise on biological effects, including terrestrial and aquatic biological effects.
This manual provides methods for evaluating construction noise effects on species and ecosystems. It covers airborne and underwater noise, attenuation, and species-specific thresholds. It includes tables and figures for noise levels, equipment, and habitat impacts.
The document is intended for project biologists to define action areas and assess noise-related disturbances during construction projects, especially those involving pile driving, geotechnical work, and marine activities.
The two most common types are point source and line source noise.
Underwater noise is measured with a hydrophone, which converts sound pressure to voltage, expressed in Pascals (Pa), pounds per square inch (psi), or decibels (dB).
Peak pressure is the instantaneous maximum overpressure, while RMS level is the mean square pressure level of the pulse, used to describe disturbance-related effects.