Mere inhalations and exhalation doesn’t mean breathing in case of scuba diving. This is a fact while you breathe on the ground level, but when underwater, you need to know various techniques required to breathe rather than simply knowing about inhaling and exhaling.

Experience over more than fifteen decades has proved that there is more to safe and healthy scuba diving than just providing the diver with enough room to breathe. To prove why this is considered true, some concepts of elementary physics needs to be applied.

Imagine that someone is standing right in front of you and is pushing you. In such a scenario you surely will fall backwards, right? But picture a situation when there are two persons pushing you, one from the front and the other from the back, then what will happen? If the intensity of the push by both the persons is the same, then you will get sandwiched between them, but you will neither fall backwards nor forwards.

Under water, this is exactly what happens, but unlike the example when there are two persons pushing you, the “push” under water will come from all sides. In such a case, your rib cage, along with the adjacent tendons and muscles provide enough rigidity to withstand the great force applied by water, lest your body would collapse!

But how much pressure can water apply on the human body? You will be amazed to know that for every 33 feet [10m] deep dive, the pressure around your body will increase by 6.70kg/sq.inch. This makes it nearly one atmosphere of 14.70pounds/sq.inch. for an increase in the depth by every 10m!

In order to withstand such a great force exerted by the water, your body will normally be pushed back. But the muscles’ and the ribs’ flexibility allows them a slight collapse prior to becoming rigid, so that the outside pressure can be balanced. This results in compression of the lungs while under the water. With deeper depths, the external pressure only increases, and this makes expansion of the lungs very difficult indeed.

Another factor influences this. Compression of air is simpler than water, which needs more force for compression. Thus the water’s pressure results in a slight compression of the lungs. This necessitates you to expand your lungs even though there is a slight collapse in it. This is done for your body to get enough supply of oxygen.

Advanced diving equipments like tanks and diving regulators are made in such a manner which facilitates the delivery of air at the level of pressure exerted by the water to aid the scuba diver manage these issues that confront him underwater. Besides, this also lets the scuba divers proper breathing at moderate depths.

Given that the density of water is very high, there is a greater requirement of oxygen under water. Expert scuba divers know how to manage the equipment and how to swim in a slow manner to save oxygen. The scuba divers must remain very calm while under water to ensurethat their heart rate is kept at a low level, and moderate amount of oxygen is used. The demand for oxygen can be disturbed if the scuba diver experiences stress of excitement due to what happens underwater.