ENRICHED AIR NITROX 2026 QUESTIONS AND
ANSWERS SURE A+
✔✔Oxygen can be toxic to all body tissues, its most noticeable and immediate effects
take place at the:
A) Central nervous system and feet
B) Lungs and circulation system
C) Lungs and central nervous system
D) Bones and blood - ✔✔Lungs and central nervous system
✔✔If you notice symptoms of CNS oxygen toxicity on yourself or your buddy while
underwater, you should immediately begin:
A) Diving deeper
B) Buddy breathing
C) Using your buddy's alternate air source
D) Controlled ascent together - ✔✔Controlled ascent together
✔✔What does ppO2 mean?
A) Partial pressure of Nitrogen
B) Partial pressure of Oxygen
C) Air
D) Nitrox - ✔✔Partial pressure of Oxygen
✔✔You can be sure that the FO2 content on the cylinder contents tag accurately
reflects the content of the Nitrox Cylinder if:
A) This was done by your buddy
B) The date on the content tag is not older than 1 day
C) This was done from a recognized dive center
, D) you personally analyze the cylinder's FO2 content, or witniss the analysis - ✔✔you
personally analyze the cylinder's FO2 content, or witniss the analysis
✔✔It is important that every nitrox cylinder be clearly labeled with a contents tag that
includes the following information:
A) MOD, Date and number of dives
B) Owner of the Total Dive system and MOD
C) FO2 content, MOD, who analyzed, Date
D) Manufacturer's name and FO2 - ✔✔FO2 content, MOD, who analyzed, Date
✔✔Always check the FO2 and MOD appearing on the contents tag, because if it
reflects a limiting ppO2 of more than 1.4 bar you should:
A) Set your computer to the higher ppO2
B) Accept it, because now you can go deeper
C) Do nothing
D) Disregard it and use more conservative ppO2 of max 1.4 bar - ✔✔Disregard it and
use more conservative ppO2 of max 1.4 bar
✔✔You need a gas source to properly calibrate your O2 Analyzer, and this gas source
should be:
A) Pure oxygen
B) All answers are correct
C) Premixed Nitrox
D) Air - ✔✔All answers are correct
✔✔If silicone lubricants, used to service first and second stages, are exposed to high
concentrations of Oxygen under pressure, this can cause:
A) Damage to the second stage only
B) Nothing
C) Fire and Explosion
D) Bad taste - ✔✔Fire and Explosion
✔✔If there is any doubt about the O2 rating of the cylinder it should:
A) Be stored in a shaded place
B) Never be filled again
C) Be handled as oxygen rated
D) Undergo a O2 cleaning prior to the next filling - ✔✔Undergo a O2 cleaning prior to
the next filling
ANSWERS SURE A+
✔✔Oxygen can be toxic to all body tissues, its most noticeable and immediate effects
take place at the:
A) Central nervous system and feet
B) Lungs and circulation system
C) Lungs and central nervous system
D) Bones and blood - ✔✔Lungs and central nervous system
✔✔If you notice symptoms of CNS oxygen toxicity on yourself or your buddy while
underwater, you should immediately begin:
A) Diving deeper
B) Buddy breathing
C) Using your buddy's alternate air source
D) Controlled ascent together - ✔✔Controlled ascent together
✔✔What does ppO2 mean?
A) Partial pressure of Nitrogen
B) Partial pressure of Oxygen
C) Air
D) Nitrox - ✔✔Partial pressure of Oxygen
✔✔You can be sure that the FO2 content on the cylinder contents tag accurately
reflects the content of the Nitrox Cylinder if:
A) This was done by your buddy
B) The date on the content tag is not older than 1 day
C) This was done from a recognized dive center
, D) you personally analyze the cylinder's FO2 content, or witniss the analysis - ✔✔you
personally analyze the cylinder's FO2 content, or witniss the analysis
✔✔It is important that every nitrox cylinder be clearly labeled with a contents tag that
includes the following information:
A) MOD, Date and number of dives
B) Owner of the Total Dive system and MOD
C) FO2 content, MOD, who analyzed, Date
D) Manufacturer's name and FO2 - ✔✔FO2 content, MOD, who analyzed, Date
✔✔Always check the FO2 and MOD appearing on the contents tag, because if it
reflects a limiting ppO2 of more than 1.4 bar you should:
A) Set your computer to the higher ppO2
B) Accept it, because now you can go deeper
C) Do nothing
D) Disregard it and use more conservative ppO2 of max 1.4 bar - ✔✔Disregard it and
use more conservative ppO2 of max 1.4 bar
✔✔You need a gas source to properly calibrate your O2 Analyzer, and this gas source
should be:
A) Pure oxygen
B) All answers are correct
C) Premixed Nitrox
D) Air - ✔✔All answers are correct
✔✔If silicone lubricants, used to service first and second stages, are exposed to high
concentrations of Oxygen under pressure, this can cause:
A) Damage to the second stage only
B) Nothing
C) Fire and Explosion
D) Bad taste - ✔✔Fire and Explosion
✔✔If there is any doubt about the O2 rating of the cylinder it should:
A) Be stored in a shaded place
B) Never be filled again
C) Be handled as oxygen rated
D) Undergo a O2 cleaning prior to the next filling - ✔✔Undergo a O2 cleaning prior to
the next filling
