ACTUAL Exam Questions and CORRECT
Answers
What are the most common symptoms of decompression sickness? - CORRECT
ANSWER - Pain in the joints, numbness, paralysis, loss of balance, muscle weakness, and
impaired thinking
What is the recommended first aid for decompression sickness? - CORRECT ANSWER -
Controlling their temperature and administering pure oxygen, then immediately getting them
airlifted to a hospital for the decompression chamber
What is the minimum concentration of oxygen required to maintain consciousness at sea level? -
CORRECT ANSWER - 16%
What is the maximum percentage of oxygen that sport divers use in a Nitrox mixture? -
CORRECT ANSWER - 40%
What is the maximum recommended depth for using 100 percent oxygen? - CORRECT
ANSWER - 20 feet
What FO2 does EAN 32 contain? - CORRECT ANSWER - 68 percent nitrogen and 32
percent oxygen
What are two reasons why EAN32 is a good choice for Nitrox diving? - CORRECT
ANSWER - Will provide you with a good combination of extended bottom time and
unrestricted depth within the sport diving range, &. using EAN32 poses less risk in terms of
exposure to oxygen than other richer mixtures.
What is the maximum partial pressure of oxygen (PO2) we use in Nitrox diving? - CORRECT
ANSWER - 1.6
, What does the term oxygen toxicity mean? - CORRECT ANSWER - condition that occurs
when the diver breathes a mixture of gas that allows the PO2 to exceed 1.6 by going too deep or
exceeding the time limit at a lower PO2
What is the primary risk associated with Nitrox diving? - CORRECT ANSWER - Oxygen
poisoning
What are the words represented by the acronym CONVENTID? - CORRECT ANSWER -
Con - convulsions, V - visual disturbances,E - ringing/auditory hallucinations, N - nausea, T -
twitching, I - irritability/apprehension, D - dizziness
What does a Nitrox tank wrap used to identify Nitrox cylinders look like? - CORRECT
ANSWER - adhesive decal, generally 10-13 cm/4-5 in in width, that is designed to
completely encircle the diameter of the tank. The tape is usually printed in yellow with bold
green letters with the words Enriched Air and/or Nitrox printed continuously on it. This tape
makes it quick and easy to spot a Nitrox bottle in a group of tanks.
What are the two most important pieces of information that will appear on a Nitrox fill tag or
label? - CORRECT ANSWER - Nitrox mixture used in the tank (FO2) and its MOD
What is the most important setting that must be made to your Nitrox computer before every
dive? - CORRECT ANSWER - oxygen % (FO2) must be set
What is an oxygen analyzer? - CORRECT ANSWER - electronic devices that are used to
measure the percentage of oxygen in a gas mixture
What are two equipment items that do not need to be cleaned for oxygen service? - CORRECT
ANSWER - buoyancy compensators and their low pressure inflators and dry suit inflation
valves