EMODnet Physics - Impulsive noise events in Pulse Block Day unit. A PBDU is the number of days in a calendar year in which impulsive sound activity occurred within the cell-grid. The product applies a common grid (10' latitude x 20' longitude) to harmonize the Regional Conventions events DBs. These data are collected at national level and contribute to the Sea Regional Convention events registry. ICES (http://underwaternoise.ices.dk/map.aspx) is hosting OSPAR and HELCOM registries. Mediterranean data are integrated from CTN under the ACCOBAMS demonstrator (http://accobams.noiseregister.org/).