All activities present some risk. There is risk involved in walking across the street or driving a car. To avoid injury while participating in an activity, people take precautions for their safety. Precautions must be taken for scuba diving just as for any other pursuit. The level of risk in diving is similar to that of flying in an airplane. Both are low-risk activities when done with well-maintained equipment according to established rules and in good environmental conditions. Unfortunately, both activities are unforgiving if you ignore the rules and recommendations designed to minimize the risks.
The following information (and the information throughout this book) will make you aware of injuries that scuba divers can incur. This information alerts you to potential hazards and, more important, helps you learn to avoid injury. If you do what you are taught to do as a diver, your risk will be minimal, and all of your diving experiences will likely be pleasant ones.
Pressure changes with depth. Changes in pressure can severely injure bodily air spaces if you are not in good health or if you fail to equalize the pressure in the bodily air spaces with the surrounding pressure. You will learn equalizing techniques as part of your training. Gases are normally dissolved in the fluids and tissues of your body. Increased pressure increases the amount of gas dissolved in your body. If you ascend too rapidly from a dive, the gases in your system can form bubbles and produce a serious illness known as decompression illness. By regulating your depth, the duration of your dive, and your rate of ascent, you can avoid decompression illness. Failure to heed depth and time schedules and ascent rates can result in serious, permanent injuries.
Diving can be strenuous at times. You need sufficient physical fitness and stamina to handle long swims, currents, and other situations that may arise. If you become winded from climbing a flight of stairs, you may need to improve your level of fitness before learning to scuba dive. Exhaustion in and under the water is hazardous. A good exercise to improve fitness for diving is swimming with fins while breathing through a snorkel.
Diving takes place in water, an alien environment. You use life-support equipment to dive, but you cannot depend entirely on the equipment for your well-being. Aquatic skills are essential in and around water. People with very weak aquatic ability can drown when minor equipment problems occur—problems that could be handled easily by a person with good water skills. To be a scuba diver, you must be comfortable in the water.
You should not be overly concerned with the potential risks of diving because the possible injuries are preventable. Learning how to dive as safely as possible is the purpose of your training. You will learn to minimize the risk of injury and maximize your enjoyment of the underwater world.