Aviation Medicine Quiz – Hypoxia

Before we understand the basics about Hypoxia, please answer to the best of your knowledge and understanding the following questions pertaining to Hypoxia in aviation.

1. What is the gaseous composition of atmosphere?

  • (a) Nitrogen 77%, Oxygen 22% and Others Gases 1%
  • (b) Nitrogen 78%, Oxygen 21% and Others Gases 1%
  • (c) Nitrogen 79%, Oxygen 20% and Others Gases 1%
  • (d) Nitrogen 78%, Oxygen 20% and Others Gases 2%

2. What is the percentage of Oxygen in the atmosphere at 33,000 ft?

  • (a) 21%
  • (b) 25%
  • (c) 30%
  • (d) 35%

3. What is the earliest indication of Hypoxia noticed by most aircrew?

  • (a) Impending sense of doom and gloom
  • (b) Vision impairment
  • (c) Hypoxia creeps in stealthily without any warning or tell-tale signs
  • (d) Impaired eye-hand coordination

4. What is the first action of a combat pilot in case of rapid decompression at an altitude of 40,000 feet?

  • (a) Nothing is required, since Oxygen mask and on-board Oxygen system shall take care of it
  • (b) Worry about decompression sickness
  • (c) Call out aircraft emergency
  • (d) Select 100% Oxygen and descend below 10,000 feet ASAP

5. What action is required by the Captain of a commercial airliner in the event of a cabin decompression at FL340?

  • (a) Start immediate descent below 10,000 feet
  • (b) Make an announcement for the benefit of the passengers
  • (c) Captain and FO to don their personal Oxygen masks and check Oxygen flow
  • (d) Prepare for diversion to the nearest airfield

6. Which type of hypoxia is most commonly seen in aviation?

  • (a) Hypoxic hypoxia
  • (b) Anaemic hypoxia
  • (c) Stagnant hypoxia
  • (d) Histotoxic hypoxia

7. Smoking makes an individual more liable to suffer from hypoxia due to:-

  • (a) False statement: smoking does not make anyone susceptible to hypoxia
  • (b) Binding of haemoglobin with the Carbon monoxide present in the smoke
  • (c) Effect of nicotine on the nervous system
  • (d) Smoking affects only those with weak lungs

8. In commercial aircraft, cabin pressure is maintained at:-

  • (a) MSL
  • (b) Below 5000 feet
  • (c) Between 6000 to 8000 feet
  • (d) Above 8000 feet

9. Time of Useful Consciousness (TUC) is:-

  • (a) Occurrence of Hypoxic insult on exposure to altitude
  • (b) Time available to recognise the development of Hypoxia and to take corrective actions to prevent its ill-effects affecting performance
  • (c) Time from commencement of flight till Hypoxic effects compromise a pilot’s performance
  • (d) Several minutes of available emergency Oxygen supply to prevent Hypoxia.

10.  military aircraft are equipped with this type of pressurisation system:-

  • (a) Isobaric system.
  • (b) Isobaric differential system
  • (c) Both of the above
  • (d) None of the above

Answers to the quiz:

1. (b);      2. (a);       3. (c);      4. (d);      5. (c);      6. (a);      7. (b);      8. (c);      9. (b);      10. (b).

If you answered 9-10 questions correctly, Congratulations! you have a good understanding of hypoxia; if you answered 6-8 answers correctly, Great start! you have a fair idea, yet it may be advisable to brush up; if 5 or less answers are correct, you need to  learn about hypoxia once more.  You can read more about Hypoxia here.

In case you wish to share your experiences of hypoxia, offer comments/feedback on this Quiz, you may use the form below or send an e-mail to avmed@avmed.in