Diving counterweight method
If the weight is appropriate, your body should float vertically at a position where your line of sight is the same as the water surface, otherwise you must increase or decrease the lead block until it is in the right position. When doing the test, you can ask the dive guide or companion to help hold the lead block and adjust the weight.
Check one last time, and then exhale. At this time, if your weight is correct, you will sink slowly.
Extrusion and drainage method of mask
(1) The external pressure increases when descending, which can cause squeezing. It must be excluded to avoid injury to the face.
(2) At this time, the nose blows slowly
(3) Return to normal state
(4) When the mask enters the water, the head rises slightly, press the upper part of the mask, and blow the nose slowly to drain the water