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Chapter 1: Introduction to Scuba Diving
Welcome, New Diver!
What Is Scuba Diving?
What Is Skin Diving?
Course Organization
Diver Certification Cards
Continuing Education Courses
Common Misconceptions
The True Risks of Diving
Facing Your Apprehensions
What Is DAN?
DAN Student Membership
Attendance & Behavior
Health Requirements
Fitness For Scuba Diving
Quiz
Chapter 2: Scuba Diving Equipment
Introduction
Introduction to Diving Equipment
Introduction to Diving Equipment page 2
Introduction to Diving Equipment page 3
Lesson 1: Mask, Snorkel, Fins
Introduction
Mask Lenses
Mask Frame,
Mask Skirt
Mask Nose Pocket
Mask Strap
Low Profile Masks, Purge Valves, and Prescription Lenses
Selecting a Mask
Defogging Your Mask
Why Divers Use Snorkels
Snorkel Mouth Piece
Snorkel Keeper
Snorkel Flex Tube
Snorkel Purge Valve
Snorkel Splash Guard
Snorkel Sizes
Why Divers Use Fins
Fin Styles
Fin Blade
Fin Straps
Fin Rails
Fin Channels
Selecting The Correct Size Fins
Rinsing Your Mask, Snorkel, and Fins
Storing Your Mask, Snorkel, and Fins
Inspecting Your Mask, Snorkel, and Fins
Quiz: Mask, Snorkel, and Fins
Lesson 2: Exposure Suits
Introduction
Why Divers Wear Exposure Suits
Selecting an Exposure Suit
Skin Suits
Wetsuit Construction
Sizing a Wetsuit
Wetsuit Styles
Wetsuit Thicknesses
Depth and Wetsuit Compression
Dry Suit Construction
Using a Dry Suit
Hoods
Booties
Gloves
Maintenance
Quiz: Exposure Suits
Lesson 3: Weights and BCD
Introduction
Why Divers Wear Weights
Hard Weights
Belts For Hard Weights
Assembling Your Weight Belt
Soft Weights
Weight Belt Quick Release
Accessory Weights
Why Divers Wear a BCD
Essential BCD Features
Power Inflator Low Pressure Hose
Power Inflator Air Inlet
Power Inflator Inflator Button
Power Inflator Deflate Button
Power Inflator Mouthpiece
Power Inflator Inflate/Defate Hose
BCD Styles
Weight-Integrated BCD
Selecting a BCD
Rinsing and Storing Your BCD
Inspecting Your Weight Belt and BCD
Quiz: Buoyancy Control Gear
Lesson 4: Scuba Tanks
Introduction
Steel Cylinders
Aluminum Cylinders
Scuba Tank Capacity & Pressure
Scuba Tank DOT Stamp
Scuba Tank Material Stamp
Scuba Tank Maximum Pressure Stamp
Scuba Tank Serial Number Stamp
Scuba Tank Manufacturer Stamp
Scuba Tank Hydro Stamp
Scuba Tank Capacity Stamp
Tank Valve Knob
Tank Valve O-Ring
Tank Valve Burst Disk
Tank Valve Snorkel Tube
"K" Valve
"J" Valve
DIN Valve
Rinsing & Storing Scuba Tanks
Filling Your Tanks
Scuba Cylinder Inspections
Quiz: Scuba Tanks
Lesson 5: Regulators and Gauges
Introduction
First Stage
Second Stage
Regulator Reliability & Safety
Selecting A Regulator
What Is An Alternate Air Source?
Octopus
Integrated Air Source
Pony Bottle
Gauge Console
Submersible Pressure Gauge
Depth Gauge
Compass Needle
Compass Lubber Line
Compass Bezel
Dive Timing Device
Dive Computers
Rinsing & Storing Your Regulator
Regulator Service & Inspection
Quiz: Regulators & Gauges
Lesson 6: Dive Accessories
Introduction
Dive Knives
Dive Lights
Logbooks
Signaling Devices
Dive Flags
Spare Parts Kit
Dive Gear bags
Quiz: Dive Accessories
Chapter 3: Scuba Diving Skills
Introduction
Introduction to Diving Skills
Introduction to Diving Skills page 2
Lesson 1: Preparing to Dive
Introduction
Benefits of the Buddy System
Finding a Dive Buddy
Qualities of a Good Dive Buddy
Dive Planning
Dive Site Assessment
Emergency Plan
Dive Activity
Reviewing Hand Signals
Surface Signals
Underwater Signals
Using Hand Signals Effectively
Assembling Your Scuba Gear
Attaching The Tank
Attaching The Regulator
Opening The Cylinder
Testing The Scuba Unit
Stowing The Scuba Unit
Disassembling Your Scuba Unit
Donning Your Dive Gear
Donning Your Wetsuit
Donning Your Weight Belt
Donning Your Scuba Unit
Donning Your Mask And Fins
Checking Your Buddy's Gear
Reviewing Special Procedures
Quiz: Dive Preparations
Lesson 2: Skin Diving Skills
Introduction
Diving Entries & Exits
Giant Stride Entry
Back Roll Entry
Seated Entry
Shore Entry
Water Exits
Boat Exit
Shore Exit
Breathing Through Your Snorkel
Clearing Your Snorkel
Surface Swimming
Flutter Kick
Dolphin Kick
Swimming With One Fin
Relieving Leg Cramps
Surface Dives
Equalizing Your Ears
Tuck Dive
Pike Dive
Feet-First Dive
Surfacing From A Skin Dive
Quiz: Skin Diving Skills
Lesson 3: Scuba Skills
Introduction
Objectives
Breathing From Your Regulator
Monitoring Your Air Supply
Clearing Your Regulator
Regulator-Snorkel Exchanges
Sweep Regulator Recovery
Reach Regulator Recovery
Breathing From A Free-Flowing Regulator
Breathing Without A Mask
Clearing Water From A Mask
Removing and Replacing A Mask
Descent Precautions
Descent Procedures
Ascent Precautions
Ascent Procedures
Maintaining Neutral Buoyancy
Using the BCD Oral Inflator
Handing Your Gear In the Water
Removing Your Weight Belt
Replacing Your Weight Belt
Removing Your BCD
Replacing Your BCD
Underwater Navigation
Natural Navigation Aids
Using Your Compass
Setting A Reciprocal Course
Quiz: Scuba Diving Skills
Lesson 4: Problem Solving Skills
Introduction
Objectives
Responding to Dive Incidents
Locating A Lost Dive Buddy
Entanglements
Air Starvation
Power Inflator Malfunction
Diver Chilling
Diver Overheating
Choking and Coughing Underwater
Seasickness
Underwater Disorientation
Out of Air Emergencies
Sharing an Alternate Air Source
Buddy Breathing
Emergency Swimming Ascent
Emergency Buoyant Ascent
Your Role As A Dive Buddy
Tired Diver Tows
Assisting Panicked Divers
Rescuing an Unconscious Diver
Towing an Unconscious Diver
Quiz: Dive Problem Solving
Chapter 4: Diving Science
Introduction
Introduction to Diving Science
Introduction to Diving Science page 2
Lesson 1: The Air Divers Breathe
Introduction
The Composition of Air
The Density of Air
Measuring Cylinder Air Weight
Quiz: The Air Divers Breathe
Lesson 2: The Effects of Water Density
Introduction
The Density of Water
Refraction of Light
Absorption of Color
Effects of Water Density on Sound
Effects of Water Density on Body Heat
Effects of Water Density on Drag
Quiz: The Effects of Water Density
Lesson 3: Buoyancy
Introduction to Buoyancy
Archimedes Principle
Three States of Buoyancy
Factors Affecting a Diver's Buoyancy
Weight and Buoyancy
Volume and Buoyancy
Breathing and Buoyancy
Quiz: Buoyancy
Lesson 4: Pressure and Diving
Introduction
Objectives
Atmospheric Pressure
Gauge Pressure
Absolute Pressure
Absolute Pressure in Salt Water
Absolute Pressure in Fresh Water
Boyle's Law
Pressure & Volume in Open Air Spaces, Descent
Pressure & Volume in Open Air Spaces, Ascent
Pressure & Volume in Closed Air Spaces
How to Calculate Pressure & Volume Changes
Exercise: Boyle's Law
Pressure and Air Density
Density & Air Consumption
Exercise: Air Consumption
Quiz: Diving and Pressure
Chapter 5: Scuba Diving Injuries
Introduction
Introduction to Diving Injuries
Introduction to Diving Injuries page 2
Lesson 1: Diving & Barotraumas
Introduction
Objectives
Anatomy of the Ear
Middle Ear Squeezes
Ear Equalization Techniques
Health and Ear Equalization
Preventing Equalization Problems
Ear Reverse Blocks
Ascending With A Reverse Block
Treating Ear Injuries
Anatomy of Your Sinuses
Sinus Squeezes
Sinus Reverse Blocks
Lung Anatomy
Causes of Lung Overexpansion Injuries
Arterial Gas Embolism, Pneumothorax
Emphysemas
Treating Lung Overexpansion Injuries
Mask Squeezes
Tooth Squeezes and Reverse Blocks
Digestive System Reverse Blocks
Quiz: Barotraumas
Lesson 2: Decompression Sickness
Introduction
Ingassing & Offgassing
Pressure & Nitrogen Absorption
What Is Decompression Sickness
Decompression Sickness Risk Factors
Symptoms of Decompression Sickness
Treating Decompression Sickness
Preventing Decompression Sickness
What Is Nitrox
Benefits of Nitrox
Using Nitrox
Quiz: Decompression Sickness
Lesson 3: Breathing at Depth
Introduction
What Is Nitrogen Narcosis
Responding to Nitrogen Narcosis
Preventing Nitrogen Narcosis
The Role of Carbon Dioxide
Benefits of Breathing Deeply
Benefits of Breathing Slowly
The Danger of Skip Breathing
What Is Shallow Water Blackout
Hyperventilation
Safe Hyperventilation
Excessive Hyperventilation
Preventing Shallow Water Blackout
Oxygen Toxicity
Carbon Monoxide Poisoning
Quiz: Breathing at Depth
Chapter 6: Dive Tables and Computers
Introduction
Introduction to Dive Tables & Computers
Introduction to Dive Tables & Computers page 2
Lesson 1: Planning Your First Dive
Introduction
Dive Planning Terms
Dive Profiles
Dive Table 1 Overview
Dive Planning Rules
Dive Planning Rules Cont.
Determining a Depth's Maximum Dive Time
Determining a Depth's Maximum Dive Time continued
Exceeding Maximum Dive Time
End Of Dive Letter Group
End Of Dive Letter Group example
End Of Dive Letter Group example 2
Quiz: Planning Your First Dive
Lesson 2: Surface Intervals
Introduction to Surface Intervals
Surface Interval Terms
Residual Nitrogen
Dive Table 2 Overview
Surface Interval Rules
Determining the Letter Group After a Surface Interval
Determining the Letter Group After a Surface Interval example 1
Determining the Letter Group After a Surface Interval example 2
Determining the Letter Group After a Surface Interval example 3
Quiz: Surface Intervals
Lesson 3: Planning Repetitive Dives
Introduction to Repetitive Dives
Dive Table Terminology
Table 3 Overview
Adjusted Maximum Dive Time
Adjusted Maximum Dive Time Example page 1
Adjusted Maximum Dive Time Example page 2
Adjusted Maximum Dive Time Example page 3
Adjusted Maximum Dive Time Example page 4
Minimum Required Surface Interval
Minimum Required Surface Interval example page 1
Minimum Required Surface Interval example page 2
Repetitive Dive Letter Group
Residual Nitrogen Time
Residual Nitrogen Time example
Total Nitrogen Time
Total Nitrogen Time example
Repetitive Dive Letter Group 2
Repetitive Dive Letter Group 3
Repetitive Dive Letter Group 4
Repetitive Dive Letter Group 5
Quiz: Repetitive Dives
Lesson 4: Dive Computers
Introduction to Dive Computers
Benefits of Dive Computers
Benefits of Dive Computers continued
Using Dive Computers
Using Dive Computers continued
Dive Computer Display Modes
Dive Computer Initialization Mode
Dive Computer Dive Mode
Dive Computer Decompression Mode
Dive Computer Scrolling Mode
Dive Computer Surface Mode
Dive Computer Log Mode
Quiz: Dive Computers
Chapter 7: Diving Environment
Introduction
Introduction to the Dive Environment page 1
Introduction to the Dive Environment page 2
Lesson 1: Dive Sites
Introduction to Dive Sites
The Beauty of Coral Reefs
Diving Coral Reefs
What Are Kelp Forests
Diving Kelp Forests
Rocky Reefs
Wharfs & Piers
Shipwrecks
Lake Diving Opportunities
Diving in Lakes
Quiz: Dive Sites
Lesson 2: Site Conditions
Introduction to Site Conditions
Objectives
Tides
Swells
Surf
Surge
What Are Currents
Longshore Currents
Rip Currents
Tidal Currents
Diving In Currents
Factors That Affect Visibility
Diving In Low Visibility
Climate and Water Temperature
Upwellings
Thermoclines
Dive Site Bottom Composition
Dive Site Bottom Contours
Quiz: Site Conditions
Lesson 3: Underwater Life
Introduction to Underwater Life
Preventing Injuries From Aquatic Life
Animals That Bite
Animals That Sting
Animals With Spines
Animals That Cut & Scrape
Treating Aquatic Life Injuries
Negative Impacts Of Diving
Effects of Poor Buoyancy Control
Abuse of Aquatic Life
Hunting & Collecting
Trash & Pollution
Positive Impacts of Diving
Quiz: Underwater Life
Chapter 8: Continuing Education
Introduction to Continuing Education Dive Classes
Advanced Scuba Diver
Rescue Scuba Diver
Master Scuba Diver
First Aid & CPR
Diver Refresher Course
Local Diving Orientation
Specialty Dive Courses
Technical Diving Courses
Leadership Diving Courses