Scuba diving is a great sport, but like other extreme activities, it has certain risks and dangers.
In any basic scuba certification course, divers learn about the dangers of scuba diving. These dangers include:
Ear and Sinus Barotrauma
Lung Expansion Injury
Decompression Sickness (Bends)
Arteral Air Embolism
Gas Toxicity (Nitrogen Narcosis and Oxygen Toxicity)
Divers not only learn about the risk, they also learn how to avoid them.
But the biggest danger in scuba diving is the reckless diver. This is the person who trys to dive without proper training or a diver who chooses to disregard their training. This bad judgement is the cause of most scuba divng injuries.