In a Spiral or Shore-Based pattern: one part of the pattern has been completed. The Anchor diver sends this signal. The Point diver lets out enough search line for the visibility range and starts the next part of the pattern.
In a Circle pattern, one of the divers wants to stop the pattern. There may be an obstruction or an equipment problem. The Point diver swims in to investigate and assist.
In a Circle pattern: the Point diver swims in to assist
and direct the recovery.
If the Point diver needs assistance, he or she give this signal
repeatedly, and the outside Sweep diver swims out to assist.
In a Spiral or Shore-Based pattern: if the Point diver sends this signal, the Anchor diver relays the signal to the Safety diver. They swim down and out to assist. If the Safety diver sends this signal, the Anchor relays the signal to the Point diver. They retrieve the search line and surface.
Receive signals by keeping tension in the line and staying in contact with the line. If you are a Sweep diver in a Circle pattern, keep one hand in light contact with the line at all times.