Figure 11. Sound Exposure Level (SEL) for the sparker source at the two highest levels throughout a full 2 hour exposure run recorded at the outer hydrophone. Note that for level 2, the peak in the middle (points inside circle) is not attributed to the sparker, but to a vessel passing close to the hydrophone, see also figure 12 for details of this. For level 3, those points clearly lying at the same level as the ship noise are from the turns (“corners”) of the racetrack, when the source was turned off. These measurements are from block 3 (Level 2) and block 4 (Level 3).
