The approach to the affection of the submarine noise in the North Atlantic Marine Subdivision has been made for a 5' x 5' grid, being the noise source navigation. To do this, a semi-quantitative index has been developed that integrates the analysis of AIS data (merchant vessels) and VMS data (fishing ships).

For both, cells have been selected according to the intensity of traffic effects based on the density of AIS and VMS signals in a month. In both cases, different intensity intervals have been established, and each case has been given a different weight. In addition, adjacent cells have been selected (classified into four ranges), giving them another way of importance depending on the proximity. The zero range coincides with the cells in which the signal density was recorded, while the first range corresponds to those cells limiting with the zero level, and so on. In Table 10 and Table 11 of the aforementioned document the applied values ​​are indicated.

The final result is the addition of all the weights in each cell, taking into account the maximum value for the bordering cells. The values range between 0 and 3.1, with the following levels of classification: Very High: > 2 / High: 1.71 - 2 / Medium: 0.41 - 1.7 / Low: 0.1 - 0, 4 / Very Low < 0.1