Air in your lungs is compressed by the pressure of the water. As the pressure of the water goes down (as you go up) then the air will expand. If you allow it to expand while trapped in your body, you can damage your ears and lungs. ascending means starting from least and moving towards highest
The reason you exhale slowly is to limit the risk of lung overexpansion injuries. The lungs are (in simplified terms) like a couple of balloons. When you inhale at depth, you fill them with compressed air. If you were to hold your breath and ascend, they would expand and eventually they would cause one of a number of potentially dangerous injuries.
The most serious lung expansion injury is arterial gas embolism (AGE) which involves bubbles being forced into the bloodstream through the lungs. It is potentially fatal.
Number one rule of Scuba diving is never ever hold your breath the pressure changes when you descend and ascend could damage your lungs. When ascending a diver does not need to just exhale they breathe normally unless they are using an emergency ascend in which case, depending on which emergency ascent they are using and for what reason, ie out of air and so on, will exhale on the way up to again ensure the pressure changes will not cause their lungs from over expansion and bursting
I hope this helps
As the diver ascends to the surface the external pressure decreases. If the air in the lungs were not exhaled, the volume in the thorax would expand, and the diver's lungs would explode.
first of all please make your question clear here divers means several well it is required to stay alive
The air in your lungs expands in volume as you get closer to the surface of any water you swim in. This is because the air was compressed when deeper due to the pressure of the water around you. This is why when scuba divers always exhale while ascending to avoid rupturing their lungs as the air expands.
Slowly
By Ditch I assume you mean discard or Jettison. obviously lead ballast which can get in the way!
The collective noun is a bubble of scuba divers.
breath without life support. :)
Self Contained Underwater Breathing Apparatus
Early and often. Divers should equalize immediately after breaking the surface, and frequently while descending. If you let the pressure build up too much, you may not be able to clear until you ascend.
scuba divers
Scuba divers who surface too quickly after a deep dive are prone to decompression sickness.
Free divers do but scuba divers do not need to. Scuba divers take their air with them and would have no need to hyperventilate.
They swim
seebees