Underwater divers are advised not to hold the breath unnecessarily while diving why
Answers
When a person is diving into the water, he should not hold his breath for reserving air for underwater breathing through life support systems.
Rather, the normal breathing is essential to keep the respiratory passage free under the varying water pressure, as the diver descends under the water.
If the air is held inside the lungs while diving, this air is compressed due to water pressure and this same air may expand while rising up in the water, creating fatal pressure over the walls of the lungs.
Underwater divers are advised not to hold the breath unnecessarily while diving because when we hold down the air the air may get compressed and it may reduce in size. Later on this compressed air while moving up in the upper layer of water will increase due to decrease in the pressure of the water which is fatal and may burst the veins and arteries and it may cause death.