Deep Diving is any dive deeper than 20 meters (60 feet). However there are different kinds of diving which gives deep diving its own specific definition. In Recreational diving, the maximum depth limit is 40 meters (130 feet).
In technical diving, a dive deeper than 60 meters (200 feet) is described as a deep dive.
However, as defined by most recreational diving agencies, a deep dive allows you to descend to 18 meters and beyond.
Risks in Deep Diving
Deep diving is relatively safe as long as you follow all the rules and procedures. However, it is important that you know the inherent risk of diving at greater depths.
When you dive, you breathe in air which is composed of oxygen, nitrogen and other gases. Your body uses the oxygen but nitrogen is eventually released over time since our body does not need it.
So, when pressure suddenly drops, like in the case of a rapid ascent, nitrogen gas inside your body expands and develops into bubbles. These bubbles are usually trapped in the joints causing severe pain. A diver with decompression sickness is treated using hyperbaric oxygen therapy inside a recompression chamber.
You will experience a narcotic effect when you accumulate too much nitrogen. The first symptoms are tingling of the fingers, dizziness and disorientation. It also affects your sight by experiencing a tunnel vision which makes reading gauges and instruments difficult. The deeper you go, the greater the effect of nitrogen narcosis is.
Rapid Air Consumption
The air you breathe will become denser as you go deeper due to increasing pressure. Meaning, you consume more air while deep diving as compared to diving at shallower depths. So it is highly recommended that you constantly monitor your pressure gauge.
You can also bring an additional small cylinder or a pony bottle, some stage a decompression tank at the safety stop line.
Rules, Recommendations and Tips for a Safe Deep Dive
- Plan your dive. Establish your maximum depth and bottom time.
- Always perform the Pre-Dive Safety Check before diving.
- Regularly monitor your depth and pressure gauge. Make sure that you have plenty of air in your tank for your ascent.
- Do not plan your dive so that it exceeds the No Decompression Limits of the dive table.
- Never dive alone and always have an experienced buddy with you.
- Never go beyond your planned depth nor exceed your bottom time.
How to Get Started
Your first deep dive should be under the supervision of a dive instructor. You can do this during your Advanced Open Water Diver course. You will be trained to dive to a depth of 30 meters (100 feet). You may also have the option to enroll in a Deep Diver Specialty course wherein you will be trained to dive as deep as 40 meters (140 feet).
After your certification, you may plan to go deep diving with an experienced dive buddy. Some deep diving sites may take you to shipwrecks or may require you to use an enriched air to extend your dive time. So you may also consider enrolling in other specialty courses like wreck diving, peak performance buoyancy and enriched air diver.