Have you ever heard divers use the word ‘narked’ or ‘narcosis’? Have you been narked yourself?
Let me tell you what it’s all about…
What is narcosis?
‘Narked’ is slang for gas narcosis, more commonly known as nitrogen narcosis. It’s the narcotic
effect that gases, not just nitrogen, can cause when breathed at greater partial pressures. Partial
pressure increases with depth, meaning if you dive on air or nitrox you’ll probably feel the narcotic
effect around 30 meters or deeper. The effects of narcosis are often compared to those of alcohol or sedatives. Some divers have reported hallucinations, euphoria, giddiness and paranoia whilst being at depth. Admittedly these extreme effects are rare and generally only felt by technical divers at depths excessive of 70 meters. When descending to 30 meters or more it’s normal for inexperienced divers to be clumsy, have impaired judgment, lack concentration and slower mechanical responses than usual
How does it work?
Okay, lets talk science. Nitrogen is an inert gas, meaning it doesn’t have a chemical reaction in the
body instead it has a physical reaction. Nitrogen is very soluble in fat, and nerve cells have a lot of
fat, which allows nitrogen to enter and disturb transmission of impulses. This reaction is similar to
anaesthetics, resulting in intoxicated symptoms. Even though narcosis isn’t harmful to you,
performance impairment could be problematic if trouble were to arise on a deep dive.
Avoid getting narked?
There is a debate between scientists whether divers build up a tolerance to narcosis or if they just
cope better with the effects due to experience. Even though narcosis isn’t typical in recreational
diving. Every diver is different, therefore the effects may be felt at varying depths. A divers susceptibility can also vary day to day and for this reason it is beneficial for divers to practice skills and tasks at depth. Obviously always dive within your comfort levels. Training dives and dives guided by professionals can help expand your comfort window. If you ever feel ‘narked’ whilst scuba diving simply ascend to shallower depths to reduce the ambient pressure, and readily reverse the effects.
Deep Diver Course
To learn about more about gases and the effects of narcosis throughly you can enrol in the Deep Diver Course with Silver Thatch Water Sports. The theoretical portion of this course can be taken online. When you arrive in the Cayman Islands you will complete three open water dives, during which the effects of narcosis will be demonstrated for you. A favourite amongst most diving instructors to teach.