Health and Hygiene

040-02-03Pablo Asensio Martínez2026-04-011 min

Intoxication

  • Alcohol: A central nervous system depressant. Affects judgment, vision, and balance.
    • Rule: 8 hours "Bottle to Throttle" (often 12-24h recommended). Limit typically 0.02% BAC.
    • Histotoxic Hypoxia: Alcohol interferes with oxygen use by cells.
  • Tobacco: Produces Carbon Monoxide (CO).
    • CO Affinity: Hemoglobin loves CO 200x more than Oxygen. Reduces oxygen carrying capacity (Anemic Hypoxia). Smoking lowers performance altitude by ~5,000 ft.

Fatigue and Sleep

Biological clock human

  • Circadian Rhythm: The body's natural 24-25 hour cycle (Body temperature drops at night, alertness drops 02:00-06:00).
  • Jet Lag: Desynchronization when crossing time zones. Worse flying East (shortening the day).
  • Sleep Inertia: Groggy feeling for 15-30 mins after waking up (especially from deep/slow-wave sleep).
  • Management: Strategic napping, bright light exposure, controlled rest.

Decompression Sickness (DCS)

Caused by nitrogen bubbles coming out of solution (Henry's Law).

  • The Bends: Joint pain.
  • The Chokes: Lung pain.
  • The Creeps: Skin itching.
  • Neuro: CNS issues.
  • Scuba Diving: Should not fly for 12 hours (non-decompression dives) or 24 hours (decompression dives) after diving.

Medication

Self-medication is discouraged.

  • Antihistamines: Drowsiness.
  • Analgesics: Can mask symptoms.
  • Antibiotics: Side effects + underlying infection.
  • Consult AME: Always consult an Aviation Medical Examiner.
Written and reviewed by

Pablo Asensio · 2026-04-01

Aeronautical engineer. Passed the thirteen EASA ATPL(A) theoretical knowledge exams studying from these very notes. Writes and reviews each topic against the Part-FCL Learning Objectives.

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