NAUI Instructor Exam Questions with
Verified Solutions
Henry's Law - ANS-The amount of gas dissolved in a liquid is directly related to its
partial pressure above the liquid.
Relationship of gas solubility and temperature - ANS-Solubility of gas decreases with
increasing temperature
(INVERSELY RELATED)
Inert gas loading in relation to body tissue - ANS-Body tissue absorbs more inert gas as
depth increases
Benefit of Dive Computer compared to Dive Tables - ANS-Gives the diver credit for
shallow portions of the dive
Cold or Strenuous dive planning rule - ANS-Use the next greater dive TIME to
determine letter group
Equilibrium as it relates to nitrogen in the body - ANS-When the pressure of nitrogen is
balanced between air and your body
Haldane surfacing ratio - ANS-Originally 2:1 - Updated with new research to 1.58:1
Tissue compartment half-time - ANS-The time required for the compartment to absorb
or eliminate half of the pressure difference between what it started with and the ambient
pressure
M-Value of tissue - ANS-The maximum allowable nitrogen (inert gas) pressure in a
specific tissue
NAUI recommendation for diving while pregnant - ANS-Do not dive while pregnant
Haldane tissue compartments - ANS-Haldane - 5 compartments
Modern Computers - Apx. 16 compartments
Tissue compartment - ANS-Mathematical model consisting of multiple theoretical
tissues and their relative halftimes
Fast compartments - short halftimes
Slow compartments - long halftimes
, Ascent rate at altitude - ANS-Slower than at sea level
Benefit of a Capillary tube depth gage - ANS-Automatically provides equivalent depth
readings
when used at higher elevations
first stage filters that appear green in color may be an indication of what? - ANS-
Corrosion from moisture in the cylinder
Boyles Law - ANS-Pressure increases as volume decreases
IVERSLEY PROPORTUNATE
Index marks on a compass - ANS-Temporarily mark the bearing that is indicated by the
north-seeking needle
Where does gas exchange occur in the body - ANS-Alveolar-capillary membrane
Two main benefits to Nitrox - ANS-Longer dive times & Shorter SIT
Inert gas means - ANS-Our bodies do not use the gas
Daltons Law - ANS-The partial pressure of any gas in a mixture is directly related to the
fraction of the gas in the total mixture
Central Nervous System (CNS) Oxygen Toxicity results from: - ANS-Relatively short
exposures to high oxygen partial pressures
ConVENTID (oxygen poisoning) - ANS-Convulsions
Vision (blurriness)
Ears (ringing)
Nausea
Twitching
Irritability
Dizziness
The maximum contingency partial pressure of oxygen (PO2) for diving nitrox is - ANS-
1.6 ATA
MOD - ANS-Maximum Operating Depth - calculated by the partial pressure of oxygen
Nitrox mixing methods - ANS-Partial pressure blending
Nitrogen separating membrane
Continuous gas blending
Verified Solutions
Henry's Law - ANS-The amount of gas dissolved in a liquid is directly related to its
partial pressure above the liquid.
Relationship of gas solubility and temperature - ANS-Solubility of gas decreases with
increasing temperature
(INVERSELY RELATED)
Inert gas loading in relation to body tissue - ANS-Body tissue absorbs more inert gas as
depth increases
Benefit of Dive Computer compared to Dive Tables - ANS-Gives the diver credit for
shallow portions of the dive
Cold or Strenuous dive planning rule - ANS-Use the next greater dive TIME to
determine letter group
Equilibrium as it relates to nitrogen in the body - ANS-When the pressure of nitrogen is
balanced between air and your body
Haldane surfacing ratio - ANS-Originally 2:1 - Updated with new research to 1.58:1
Tissue compartment half-time - ANS-The time required for the compartment to absorb
or eliminate half of the pressure difference between what it started with and the ambient
pressure
M-Value of tissue - ANS-The maximum allowable nitrogen (inert gas) pressure in a
specific tissue
NAUI recommendation for diving while pregnant - ANS-Do not dive while pregnant
Haldane tissue compartments - ANS-Haldane - 5 compartments
Modern Computers - Apx. 16 compartments
Tissue compartment - ANS-Mathematical model consisting of multiple theoretical
tissues and their relative halftimes
Fast compartments - short halftimes
Slow compartments - long halftimes
, Ascent rate at altitude - ANS-Slower than at sea level
Benefit of a Capillary tube depth gage - ANS-Automatically provides equivalent depth
readings
when used at higher elevations
first stage filters that appear green in color may be an indication of what? - ANS-
Corrosion from moisture in the cylinder
Boyles Law - ANS-Pressure increases as volume decreases
IVERSLEY PROPORTUNATE
Index marks on a compass - ANS-Temporarily mark the bearing that is indicated by the
north-seeking needle
Where does gas exchange occur in the body - ANS-Alveolar-capillary membrane
Two main benefits to Nitrox - ANS-Longer dive times & Shorter SIT
Inert gas means - ANS-Our bodies do not use the gas
Daltons Law - ANS-The partial pressure of any gas in a mixture is directly related to the
fraction of the gas in the total mixture
Central Nervous System (CNS) Oxygen Toxicity results from: - ANS-Relatively short
exposures to high oxygen partial pressures
ConVENTID (oxygen poisoning) - ANS-Convulsions
Vision (blurriness)
Ears (ringing)
Nausea
Twitching
Irritability
Dizziness
The maximum contingency partial pressure of oxygen (PO2) for diving nitrox is - ANS-
1.6 ATA
MOD - ANS-Maximum Operating Depth - calculated by the partial pressure of oxygen
Nitrox mixing methods - ANS-Partial pressure blending
Nitrogen separating membrane
Continuous gas blending
