Andy Davisnarcosis - Andy Davis Technical Diving Blog

Tag Archive: narcosis


Originally posted 2019-02-22 12:34:35. Scuba Q and A: Why Do Deep Divers Use Helium? Q. Why is helium preferred over nitrogen for diluting oxygen during deep sea diving? Answer: There are three reasons why helium becomes a necessary addition to breathing gas as depth increases: Oxygen Toxicity Oxygen is known to cause central nervous system […]


Originally posted 2019-02-22 12:12:32. Scuba Q and A: How Deep Can You Dive Using Air? Q. How deep can someone scuba dive using normal air? Answer:  There are a number of factors that determine the Maximum Operating Depth (MOD) of any gas mixture. These include: Inert-Gas Narcosis Inert gas narcosis using air begins to become […]


Originally posted 2018-03-07 23:56:52. Scuba Q and A Question:   I was taught that “recreational divers plan all dives to be no stop dives” and also that most agencies consider 40m /130 feet as the maximum depth for recreational deep diving.  That seems inconsistent when my dive computer allows me to dive below 40m/130 feet and […]


Originally posted 2018-03-07 23:55:40. Nitrogen Narcosis – Perceptions of Susceptibility Examining the human factors influencing diver perceptions of susceptibility to nitrogen narcosis.  By Andy Davis Nitrogen narcosis is a hyperbaric neurological phenomenon. Its existence, symptoms and onset are known, even if medical science has not yet explained the physiological mechanisms causing it. Individual susceptibility to […]


Does Nitrogen Narcosis Impairment Persist? by Andy Davis. A new study on nitrogen narcosis challenges the long held presumption that nitrogen narcosis impairment dissipates immediately on ascent from depth.  A scientific study, ‘Persistence of Critical Flicker Fusion Frequency Impairment; Evidence of Prolonged Nitrogen Narcosis,’ first published in 2012 in the European Journal of Applied Physiology, by Costantino […]