New bulletin issued on underwater sound impact evaluation
The evaluation of environmental impacts from anthropogenic underwater sound often involves a comparison between predicted sound levels and threshold criteria for effects, as well as consideration of contemporary published science, guidance and standards.
Substantive updates were made to internationally-recognised technical guidance and published scientific information on auditory effects in marine mammals and turtles in late 2024 and early 2025. These included:
- United States (U.S.) National Marine Fisheries Service (NMFS) 2024 update to Technical Guidance for Assessing the Effects of Anthropogenic Sound on Marine Mammal Hearing (NMFS 2024).
- U.S. Navy Phase 4 Report on Criteria and Thresholds for U.S. Navy Acoustic and Explosive Effects Analysis (Revision 2025.1; Accomando et al. 2025).
Both publications provide contemporary scientific information and threshold criteria for auditory effects that may arise from exposure to anthropogenic underwater sound.
NOPSEMA has published a new environment bulletin in response to queries it has received regarding the two publications. The bulletin provides further information and advice regarding the application of the NMFS (2024) Technical Guidance and the Accomando et al. (2025) in environmental impact and risk assessments under the Offshore Petroleum and Greenhouse Gas Storage (Environment) Regulations 2023.