10 NAUI Nitrox Diver
Contents
Preface ...........................................................12
Enrollment ........................................................12
Responsibilities ................................................12
Getting the Most From the Course ..................13
1 Introduction 14
Learning Goals ..........................................15
What is Nitrox? ..........................................15
A Bit of History ..........................................15
Wh y Dive With Enriched Air Nitrox? .......19
Common Misconceptions
About Nitrox ............................................20
Myth 1: "Nitrox is for technical diving." ...20
Myth 2: "Nitrox is for deep diving." .........21
Myth 3: "If you dive with nitrox
you won't get bent." ..............................21
Myth 4: "Nitrox is safer than air." .............21
Myth 5:"If you dive with nitrox
you won't get narcosis." ........................21
Myth 6: "It is hard to dive with nitrox." .....21
Terminology .............................................21
Pioneers Paving the Way .......................22
2 Gases and Gas Mixtures 24
Learning Goals ........................................25
What’s in Air? ..........................................25
Some Facts About Individual Gases ....26
Oxygen ....................................................26
Nitrogen ..................................................26
Argon ......................................................26
Carbon Dioxide .......................................26
Helium and Neon ....................................26
How Gases Behave .................................27
Boyle’s Law: Pressure,
Volume, and Density .............................27
Henry’s Law: The Solubility of Gases .....28
Dalton’s Law: Partial Pressure
in Gas Mixtures .....................................29
Converting Between
Depth and Pressure ..............................30
Converting Between Depth and
Pressure by Formula ..............................30
Converting Between Depth and
Pressure With a Table ............................31
Calculating Partial Pressures ................32
Determining Oxygen Partial
Pressure by Table .................................33
The NAUI MobileTM Application...............33
3 The Physiology of Diving and Nitrox 36
Learning Goals ........................................37
Nitrogen: Narcosis and
Decompression Sickness ....................37
Nitrogen Narcosis ...................................37
Decompression Sickness .......................38
Oxygen: The Good and the Bad ............40
Oxygen and Metabolism .........................40
Physiological Effects of Low Oxygen
Levels (Hypoxia) ...................................40
Physiological Effects of High
Oxygen Levels ......................................41
Central Nervous System Toxicity ..........41
Managing Oxygen Exposure ..................43
Avoiding CNS Toxicity ............................44
Professionals Leading the Way .............44
4 Choosing the Best Nitrox Mix 46
Learning Goals ........................................47
The ODIGTML Dive Planning System ...47
Oxygen ....................................................48
Decompression .......................................48
Inert Gas Narcosis ..................................48
Gas Management ...................................48
Thermal ...................................................49
Mission ....................................................49
Logistics ..................................................49
Enriched Air Nitrox Mixtures .................49
Maximum Operating Depth ....................51
Maximum Operating Depth by Table .....51
Calculating Maximum
Operating Depth ...................................51
Using the NAUI MobileTM App
to Determine MOD .................................52
Choosing Your “Best Mix” .................... 52
Best Mix by Table .................................. 52
Calculating Best Mix .............................. 52
Using the NAUI MobileTM App to
Determine Best Mix ................................ 53
Pioneers Paving the Way .......................54
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