Why do scuba divers need to exhale air when they ascend to the surface of the water?

Answer 1

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

Answer 2

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.

Answer 3

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

Answer 4

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.

Answer 5

first of all please make your question clear here divers means several well it is required to stay alive