Diving Physiology
Focuses on how the human body responds to immersion, pressure, and breathing underwater. You can gain a clear understanding of the body systems most affected by diving and the physiological risks associated with depth, gas exposure, and ascent and descent.
Key areas covered include:
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The structure and function of the circulatory system and how immersion affects the heart and blood flow
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The anatomy and function of the respiratory system, including breathing mechanics and gas exchange
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Breathing techniques, breathing effort, and how equipment design affects breathing
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Physiological dead space, tidal volume, breathing rate, and gas consumption
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Barotrauma of air spaces including ears, sinuses, lungs, teeth, and gastrointestinal tract
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Gas toxicity, including the effects of nitrogen, oxygen, carbon dioxide, carbon monoxide, helium, and other gases
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Decompression sickness and how dissolved gases affect the body during ascent
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Physical, sensory, physiological, and psychological changes experienced in the diving environment, including vision, sound, balance, and perception
By the end of this section, you will understand how and why the body reacts underwater, how diving-related injuries occur, and how correct techniques and awareness reduce risk.
Course Features
- Lectures 46
- Quizzes 7
- Duration Lifetime access
- Skill level All levels
- Language English
- Students 485
- Certificate Yes
- Assessments Self
- 9 Sections
- 46 Lessons
- Lifetime
- Introduction1
- The Circulatory System
Objective: Explain how the circulatory system supports oxygen delivery and diver performance.
Knowledge: Describe heart structure, blood flow through the heart, and cardiovascular fitness requirements.
Skills: Interpret circulatory risk factors (e.g., PFO) and apply safe diving practices.
6 - The Respiratory System
Objective: Explain respiratory anatomy and how breathing supports gas exchange during diving.
Knowledge: Describe airway structure, lung volumes, gas exchange, and breathing emergencies.
Skills: Identify early signs of respiratory distress and apply correct response priorities.
10- 3.1Function of the Respiratory System
- 3.2Applied Anatomy and Physiology
- 3.3Respiration – Breathing
- 3.4Tidal Volume
- 3.5Respiratory Minute Volume (RMV)
- 3.6Physiological Dead Air Space and Snorkeling
- 3.7Lung Volumes
- 3.8Pulmonary Barotrauma
- 3.9Breathing Emergencies
- 3.10Practice Test – Respiratory System68 Minutes34 Questions
- Breathing
Objective: Explain how pressure, exertion and equipment affect breathing in diving operations.
Knowledge: Describe work of breathing, gas density, RMV, and dead space effects.
Skills: Apply safe breathing techniques and recognise risks of CO₂ retention or panic.
6 - Barotrauma of Air Spaces
Objective: Identify barotrauma risks affecting air spaces and explain prevention strategies.
Knowledge: Describe causes, symptoms and prevention of ear, sinus, lung, dental and gut barotrauma.
Skills: Apply safe equalisation and ascent/descent decision-making to prevent pressure injuries.
7 - Gas uptake and Gas Toxicity
Objective: Explain gas uptake and identify common gas toxicities affecting divers.
Knowledge: Describe gas solubility, tissue loading, and effects of narcosis, CO₂, CO and oxygen toxicity.
Skills: Recognise symptoms and apply immediate safety actions for gas toxicity scenarios.
9 - Gas Elimination and Decompression Sickness
Objective: Explain outgassing and decompression sickness and identify early warning signs.
Knowledge: Describe bubble formation, silent bubbles and the mechanism and symptoms of DCS.
Skills: Apply correct response priorities and escalation actions when DCS is suspected.
3 - Diving Environments
Objective: Explain how environmental and psychological stressors affect diver physiology and safety.
Knowledge: Describe effects of vision, sound, balance, temperature, ventilation, psychological stress and stressors.
Skills: Apply stress management and safe operational awareness in diving scenario decisions.
10 - Final Exam
Objective: Demonstrate competence in diving physiology through scenario-based assessments and final examination.
Knowledge: Explain physiology principles, injuries, and risks relevant to diving operations.
Skills: Apply physiology knowledge to interpret symptoms, risks, and safe responses under exam conditions.
1
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