Tag Archive: oxygen

Scuba Q and A: Why Do Decompression Divers Use Nitrox? Q. Why do decompression divers need to use nitrox in the shallower part of their dive? Answer: A diver absorbs or releases inert gas based on the positive or negative partial pressure differential of those gases in their breathing mix and body tissues. We only […]

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 (CNS) toxicity at higher […]

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 debilitating through anaesthetic effect […]
OXYGEN EXPOSURE MANAGEMENT by Richard D. Vann Oxygen metabolism is the primary energy source in higher life forms, but when oxygen enters the metabolic process prematurely, reactive oxygen species can form which interfere with normal function and cause convulsions or other symptoms of oxygen toxicity. Immersion, exercise, and inspired carbon dioxide increase susceptibility to oxygen […]

The Physics of Diving – Scuba Gas Laws A concise explanation of the critical scuba gas laws for divers by Andy Davis Scuba diving is all about getting gas into your body while you are underwater. What complicates scuba diving is the way gasses behaves at depth, under pressure, in your body and in your […]

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 […]

Decompression Gases – Efficiency Ratios Deco Gas Efficiency Ratio Air 1:1 32% 1:1.6 36% 1:1.21 40% 1:1.26 50% 1:1.32 80% 1:1.36 100% 1:1.40 Theoretical efficiency ratios for decompression gas options.