NOAA is developing comprehensive guidance on sound characteristics likely to cause injury and behavioral disruption in the context of the Marine Mammal Protection Act (MMPA), Endangered Species Act (ESA) and other statutes. Until formal guidance is available, NOAA Fisheries uses conservative thresholds of received sound pressure levels from broad band sounds that may cause behavioral disturbance and injury. These conservative thresholds are applied in MMPA permits and Endangered Species Act Section 7 consultations for marine mammals to evaluate the potential for sound effects. The criterion levels specified are specific to the levels of harassment permitted under the MMPA.
Interim Sound Threshold Guidance
National Oceanic and Atmospheric Administration (2016). Interim Sound Threshold Guidance. Retrieved from http://www.westcoast.fisheries.noaa.gov/protected_species/marine_mammals/threshold_guidance.html