The recommended calculation of Safety Depth is: Draught + Squat + Required Underkeel Clearance – Height of Tide (HoT)

Safety contour is the next chartered contour beyond the safety depth.

For example, if the chart on display has 5m and 10m contours and you have set your safety depth at 6m, the 10m contour will be used as the safety contour.

We now need to look at how we can view the safety contour.  The safety contour is a key menu to understand as it is the automatic alarm feature when standing into danger