| Breathing underwater while scuba diving is not just | | | | To withstand such great pressure, you body should |
| about inhaling and exhaling. This is true of breathing | | | | ideally be pushing back. However, the flexibility of the |
| on ground but when you get underwater, even if | | | | ribs and muscles allows them to collapse slightly |
| you have an air tank on you, you will need to know | | | | before becoming rigid in order to balance the outside |
| a lot more about breathing than simply how to inhale | | | | pressure. This causes your lungs to compress slightly |
| or exhale. | | | | when you are under water. The deeper you go, the |
| Over a hundred and fifty years of studying scuba | | | | greater the outside pressure and thereby the more |
| diving experience has shown that healthy and safe | | | | difficult it is for your lungs to expand. |
| dive takes more than just giving the diver enough air | | | | There is another factor that is at work. While water |
| to breathe. Let us try and use some elementary | | | | needs considerable force to be compressed, air is |
| physics to understand why this is true. | | | | relatively easier to compress. Therefore, the pressure |
| Okay, here's a visualization exercise. Try and imagine | | | | of water outside compresses the air in your lungs to |
| someone standing in front of you and trying to push | | | | a certain degree. In order to supply your body with |
| you. What happens to you? You will tip and fall | | | | enough oxygen, you have to expand your lungs |
| backward. Now what if there were two people - one | | | | despite the slight collapse and the air compression. |
| pushing you from the front and one from the back. | | | | Modern equipment like diving regulators and tanks are |
| You will probably remain standing if the two forces | | | | designed in a way that the air is delivered at the |
| are equal but you may get squeezed by them. | | | | pressure levels of the surrounding water to help the |
| This is what happens when you are in the water, | | | | scuba diver cope with these underwater issues. This |
| except that the "push force" comes from all sides | | | | allows scuba divers to breathe easily up to moderate |
| not just two sides. So how does your body cope | | | | depths but not great depths. |
| with all this pressure? Well, it's your rib cage, and | | | | The oxygen requirement underwater is higher owing |
| surrounding muscles and tendons that provide the | | | | to the high density of the surrounding water. Skilled |
| rigidity to withstand this enormous pressure, | | | | scuba divers learn ways to work with the equipment |
| otherwise your body would simply collapse. | | | | and swim slowly in order to conserve oxygen. |
| Now you will ask, how much pressure can water | | | | Scuba divers also make sure they remain calm |
| exert? The answer is bound to surprise you. Every | | | | underwater, so that their heart rate is low and their |
| 10 m (33 feet) deep that you dive will increase the | | | | oxygen use is moderate. Excitement due to |
| pressure around you by 6.7 kg per square inch. This | | | | fascinating underwater sights and stress caused by |
| means about one atmosphere or 14.7 lbs per square | | | | possible dangers can all affect the need for oxygen. |
| inch of increased pressure every 10 m!! | | | | So, learn to breathe properly and have a safe dive! |