Today, Fu-sama brings you:
HORRIBLEand goodTHINGS ABOUT DIVING
Note: I'm not gonna post any bloody pictures or anything, since I don't have any. So you'll have to do with some randomly placed pictures of me in scuba gear, and some fish.
There are a lot of ways to get hurt when diving. And the creatures who live underwater are the least of your concerns.
No, the biggest troublemaker when diving is YOU.
Yeah, I'm looking at you, Joe.
Anyway. Only stupid people get hurt when diving, so that includes you too. Not just you Joe. The people reading this, too.
And how are you stupid? Whoo, I don't have time to list that. Wikipedia exists for

a reason. Or just look out your window (Or in the mirror, for that sake). Stupidity is everywhere. And there's no limit to it.
Most diving accidents happen at the surface, sometimes even before you touch the water. You usually survive from these accidents, as they include tripping on the boat, hitting something as you jump in the water, etc.
But underwater, it's different.
So, one million dollar question? Wait, screw that. One million euro question. That's better. Then you can actually afford something.
How are you stupid underwater?
Answerr isss...
You run out of air.
Yeah, facepalm inducing, isn't it? Statistics say that you're more likely to get eaten by a shark than run out of air. And you're more likely to get hit by a car while walking on the sidewalk, than get eaten by a shark. Heck, you could probably compare running out of air to suffocating on the street, becaue you forgot to breathe. I love numbers.
There are various things following running out of air. First of, you panic. Well, most do, but those who don't still have good reason to. Next is, you want air. And you'll probably try to rip out your buddy's regulator in order to get some yourself. BUT, this is where stupidity comes in, because you're not with your buddy!forsomereason
Soo, you want to go where there's air. The surface. So, you swim, up.
Now, there's a lot of ways to continue from here, but I'll take the worst case.
You hold your breath as you swim up with rapid speed.
And now it gets hurtful.
The compressed air you'd breathed in from the tank on your back begins to expand in your lungs, as the pressure around you becomes lower and lower. Your lungs expand towards your ribs, without the slightest feeling of discomfort. Suddenly your lung explodes in multiple places, as the air desperately tries to escape your body. You either instantly die, suffocate to death, is paralyzed from top to toe, or if you're lucky, pass out from the excruciating pain.
Slowly, you'll ascend to the surface, unconscious or dead, where pinkish foam and lung tissue escapes from your mouth and nose in a grotesque manner.
If you survive this, you'll probably never dive again, and maybe even never be able to breathe properly again. And if you ascended too fast, you'll probably have DCS, too, since it was from 18 meters.

This is the most serious accident that can happen when scuba diving. Now, you're probably thinking "OMG thats so crazy, but youll naturally hold your breath when out of air wont you??+". Yes, you will. But both this and DCS (Which I will get to later) can be well explained with a soda bottle.
The air inside a bottle of soda is compressed, to seal the bottle and keep foreign nasty things from entering. When you open it, you relieve the pressure, and bubbles rise in the soda. If there're too many bubbles, you naturally either open it quickly and let out the full pressure, usually resulting in soda all over your hand and the bottle. Or, you slowly open the bottle, little by little relieving the pressure, as it adapts to the pressure outside. If you do this correctly, the bubbles won't even rise, and you won't have soda all over.
So the solution to keep your lungs from exploding is: Relieve pressure as you ascend.
You let out a tiny stream of bubbles from your mouth (Usually humming works) as you swim upwards. This will keep the air pressure inside your lungs stable, as it adapts to the outside pressure.
Now, to DCS. DCS stands for De-Compression Sickness, also known as the 'bends'. This is the 'accident' where you ascend too fast, OR dive at too deep depths, for too long. Nitrogen bubbles form in your blood veins, and if you've exceeded the maximum dive time at a specific depth, these bubbles will get larger, and if you're unlucky, they'll enter your arteries, and then your heart, which either kills you or gives you a stroke. They can also enter your brain, and the result will probably be even nastier.
This is called AGE, Arterial Gas Embolism.
I'm not going to go completely into detail how it works, but it's the same as the soda bottle concept.
After each dive, you will have a slight amount of bubbles in your body, and you'll be fizzing like a coke for a few hours after you resurface. This is not serious at all.
However, if you do dive too much and get DCS, you'll experience pain in your joints, which can be reduced by bending the joint to a more comfortable position. This is often found in the back or the shoulders, resulting in people bending forwards to relieve the pain. This is why it's called the 'bends'.
Other symptoms include confusion, memory loss, blurred vision, extreme fatigue, burning sensation, twitching, shortness of breath, dry constant cough, swollen skin, and many other nasty things.
So, how do you avoid it? First of all, keep a schedule of your dives. This is simpler than it sounds, but not very interesting to read about. In short: Know how long you dived for, maximum depth, water temperature, etc.
Second, always ascend slowly. No more than 9m/minute. This is about as fast as tiny bubbles ascend. If you've doven to more than 16ish meters, make sure to make a precautionary decompression stop at 5 meters, for 5 minutes.
If you do get DCS, you'll be put in a decompression chamber for a day or two, where the pressure inside is lowered to 15 meters or so.

Yeah, pressure is some really nasty stuff.
Oh right, the good things about diving? Uhmm.
It's like flying underwater.
Happy birthday, dad. (He asked for it himself!)
-Fu