While we were sitting around eating at Kyle’s party yesterday, I overheard a conversation regarding “the bends” — how and why it happens when going scuba diving.Don’t know why this came up, and I wasn’t really paying attention, so Linda said to do some research, and blog about it. Here it is:
One way to think about the bends is to shake a bottle of soda and open it quickly — a disaster. However, by waiting to open it, disaster is avoided.
Similarly when scuba diving, rising to the surface slowly (decompressing) safely releases nitrogen gases that built up in the diver’s blood.
Conversely, rising too quickly releases the nitrogen, causing a painful condition called the bends.
So, how does nitrogen get into the diver’s body? From the oxygen tank that’s part of the diver’s SCUBA system.
Since the pressure on our body is much greater under water than when on land (water is much heavier than air), the SCUBA oxygen tank must be filled at a higher pressure, or the air won’t come out.
The oxygen in the tank contains some nitrogen, and because it’s highly pressurized, nitrogen enters the diver body when breathed in, just like gases carbonating a liquid substance.
P.S. for the scientifically inclined, air pressure at sea level is 14.7 PSI (pounds per square inch). Diving 10 meters down increases the pressure by a factor of two. 20 meters by three, etc.