Identify areas of concern where sources of noise (ports, underwater acoustic deterrents,
pile driving, busy streets, airports, railways, industry, etc.) are near to natural habitats,
including marine habitats. Count occurrences of noise above a 55 decibel threshold on
land (or a 170 decibel threshold underwater) in at least 5 outdoor locations within the
areas of concern in the city for at least 30 minutes each during the most noisy time
period of a typical day (Benliay et al., 2019).

A noise map of the areas of concern can be used in lieu of these measurements to
report on extent of natural habitats adjacent to sources of noise above 55 decibels on
land or 170 decibels underwater.