Deep Diving

Qualification required: Advanced up to + - 30m only.

Deep diving is the means to an end and not an end in itself. Most wrecks require visiting depths below 18metres, the Open Water qualification cut-off. Aquatic species vary in the shallower parts of the ocean and exploring subjects for deep water photography. Deep diving generally caps at 40m/130 feet below at which commercial and other forms of highly technical trained areas like navy divers take over. Equipment requirements here vary in accordance, using six cylinders, multiples regulators, extended decompression stops, special helium breathing gases and much training and experience.

Deeper dives need to be taken seriously and awareness of the dangers of deep diving as well as the importance of matching the depth of your dive to your qualification and experience is imperative and will allow for a more rewarding experience. One of the hazards is Nitrogen Narcosis which sets in with more impact the deeper one dives. Another is decompression sickness, subject to repetitive dives on a single tank of air as well as fading light making it harder to read instruments.

Dive equipment for deep descents is specialized and it is recommended that your regulator, BCD, tanks and such are serviced thoroughly before embarking on the exploration, spare weights, dive computers and emergency oxygen are just a few examples of diving essentials. In the event that you are unsure of what to take you should be diving with a seasoned diver or instructor.

Special attentions should be given to studying the role played by the following aspects of diving when exploring the ocean deeper than 18m:
• Maintaining control during descent and ascent.
• Buddy contact
• Specialized breathing techniques and air supply control.
• Decompression stops.

Nitrogen Narcosis

Commonly described as the process of 'poisoning' that occurs when breathing nitrogen under pressure. Tolerance levels differ from person to person it is important to note the side effects.

The signs:
• Anxiety, sleepiness or drowsiness.
• Dlation and a false sense of security.
• Short term memory loss.
• Impaired judgment slowed thinking.
• Irrational behavior.

Preventing getting 'narked':
• If you notice symptoms ascend until the side effects subside.
• Stay shallow

Decompression Sickness

Recall the effects on a balloon inflating and deflating under the pressure of large amounts of water and the result of this experiment will assist you in understanding lung over-expansion injuries and decompression sickness.

Thus holding your breath while ascending can literally cause your lungs to explode or rupture.

Be on the lookout as symptoms can appear during or straight after the dive and even up to 48 hours after.

Signs:
• Tingling, paralysis, dizziness or paralysis.
• Breathing difficulty and coughing spasms.
• Pain in arms legs, joints.
• A rash and or itchy skin.
• Collapse and unconsciousness
Prevention:
• Stick to the dive tables religiously to avoid dive errors which are the main cause of decompression illness.
• Never dive to the limits.
• Consider you age and weight (for higher and thus more dangerous nitrogen absorption factors)
• Heavy exertion accelerating hear rate which increases circulation and thus absorption.
• Injuries and illness.
• Dehydration or conversely alcohol use.
• Cold water effects on circulation Carbon dioxide build-up due to holding your breath instead of breathing properly.
• Flying after diving and altitude diving.

Decompression chambers, breathing pure oxygen and CPR are methods of treating decompression illness.