Scuba diving is a great activity for people who like adventure and seeing life beneath the sea. But scuba diving is not always safe. It is important to know what dangers you face and what you should do.

There are various types of scuba equipment that are used by divers. Some are designed to help the diver operate comfortably while others are used for special purposes.

The first scuba systems were designed by Henry Fleuss in 1878. These systems included a tank and a regulator that was attached to the tank. An air pressure gauge was also included. This device controlled the pressure of the air delivered to the diver.

A buoyancy control device is also used by divers to keep the diver in a neutral state of buoyancy. It is also used to ensure that the diver is not too deep or too shallow.

Typically, scuba divers wear a wet suit, a dry suit, a mask and fins. They may also carry a strobe, lights, and an emergency locator beacon.

Before beginning a dive, the diver must be trained to use the equipment. He or she must also learn the proper procedures for entering and exiting the water.

Underwater conditions can be physically and psychologically difficult. Many scuba divers descend into the depths for commercial or scientific reasons.

Some divers, for medical or recreational purposes, are prone to decompression sickness. This condition is caused by bubbles and overexpansion of lung gases. Lung gases can enter the pulmonary return circulation, which can lead to a range of dangerous medical problems.