NITROX EXAM GUIDE QUESTIONS
WITH CORRECT ANSWERS
If we heat a gas, we are adding _________, increasing the speed of the molecules
and the force of the impacts -Answer-Energy
Which law states: "At a constant temperature, the volume of a gas varies inversely
with absolute pressure, while the density of a gas varies inversely with absolute
pressure?" -Answer-Boyle's Law
Which law states: "The amount of any given gas that will dissolve in a liquid at a
given temperature is a function of the partial pressure of the gas that is in contact
with the liquid and the solubility coefficient of the gas in the particular liquid?" -
Answer-Henry's Law
What is the portion of the total gas pressure exerted by a single gas in a mixture of
gases? -Answer-Partial Pressure
Which law states: "The total pressure exerted by a mixture of gases is equal to the
sum of the pressures that would be exerted by each of the gases if it alone were
present and occupied volume."? -Answer-Dalton's Law
Each __________ that you descend in the ocean adds another atmosphere of
pressure to the one atmosphere of surface pressure. -Answer-10 meters (33 feet)
When you are at a depth of 20 meters of seawater (msw)/66 feet of seawater (fsw),
the absolute pressure is what? -Answer-3 ata
To convert depth to absolute pressure, you first find the water (hydrostatic) pressure
in atmospheres and then add what? -Answer-One atmosphere for the sea level air
pressure
To determine the partial pressure of a gas in a mixture, you multiply what two
numbers? -Answer-Gas fraction
Absolute pressure
Using the Oxygen Partial Pressure at Depth table, what is PO2 of EAN34 at a depth
of 24 msw (80fsw)? -Answer-1.16 ata
A stuporous condition characterized by impaired mental and physical performance
and changes in mood and behavior is known as _____. -Answer-Nitrogen narcosis
The mechanisms of nitrogen narcosis are thought to be similar to what? -Answer-
Gases used in anesthesia
What are the terms for absorption and elimination of nitrogen during a dive? -
Answer-Ingassing and offgassing
, List the signs and symptoms of decompression sickness? -Answer-Excessive fatigue
weakness and tingling in limbs
limb and join pain and dysfunction
skin rashes and itching
vertigo
loss of sensation
Paralysis
Death
What is the primary waster product in metabolism? -Answer-Carbon Dioxide
When do symptoms of hypoxia appear? -Answer-When the partial pressure of
oxygen falls below 0.16 ata
Central nervous system toxicity can result from what? Pulmonary toxicity? -Answer-
Short exposure to high partial pressure of oxygen;
Prolonged exposure to elevated partial pressure of oxygen
The recommended maximum PO2 for enriched air nitrox diving is: -Answer-1.4 ata
What are some of the many factors that can increase your susceptibility to CNS
oxygen toxicity? -Answer-Heavy exercising
Increased carbon dioxide buildup
Chilling
Water immersion
What does the mnemonic acronym "ConVENTID" stand for? -Answer-Convulsions
Visual disturbances
Ears
Nausea
Twitching and tingling
Irritability
Dizziness or dyspnea
What are the two standard nitrox mixes? -Answer-32% and 36% oxygen
What is the Maximum Operating Depth (MOD)? -Answer-The maximum operating
depth that should be dived with a given nitrox mixture
Using the Maximum Operating Depth table, what is the MOD for EAN36 if the PO2 is
not to exceed 1.4 ata? -Answer-28 msw (95 fsw)
What is the first thing you need to find when calculating the maximum operating
depth for any nitrox mixture? -Answer-Find the total pressure that it takes to produce
the maximum acceptable oxygen partial pressure, and then convert it to a depth
What is the range of oxygen percentages you can set on the NAUI mobile App
calculators? -Answer-21%-40%
WITH CORRECT ANSWERS
If we heat a gas, we are adding _________, increasing the speed of the molecules
and the force of the impacts -Answer-Energy
Which law states: "At a constant temperature, the volume of a gas varies inversely
with absolute pressure, while the density of a gas varies inversely with absolute
pressure?" -Answer-Boyle's Law
Which law states: "The amount of any given gas that will dissolve in a liquid at a
given temperature is a function of the partial pressure of the gas that is in contact
with the liquid and the solubility coefficient of the gas in the particular liquid?" -
Answer-Henry's Law
What is the portion of the total gas pressure exerted by a single gas in a mixture of
gases? -Answer-Partial Pressure
Which law states: "The total pressure exerted by a mixture of gases is equal to the
sum of the pressures that would be exerted by each of the gases if it alone were
present and occupied volume."? -Answer-Dalton's Law
Each __________ that you descend in the ocean adds another atmosphere of
pressure to the one atmosphere of surface pressure. -Answer-10 meters (33 feet)
When you are at a depth of 20 meters of seawater (msw)/66 feet of seawater (fsw),
the absolute pressure is what? -Answer-3 ata
To convert depth to absolute pressure, you first find the water (hydrostatic) pressure
in atmospheres and then add what? -Answer-One atmosphere for the sea level air
pressure
To determine the partial pressure of a gas in a mixture, you multiply what two
numbers? -Answer-Gas fraction
Absolute pressure
Using the Oxygen Partial Pressure at Depth table, what is PO2 of EAN34 at a depth
of 24 msw (80fsw)? -Answer-1.16 ata
A stuporous condition characterized by impaired mental and physical performance
and changes in mood and behavior is known as _____. -Answer-Nitrogen narcosis
The mechanisms of nitrogen narcosis are thought to be similar to what? -Answer-
Gases used in anesthesia
What are the terms for absorption and elimination of nitrogen during a dive? -
Answer-Ingassing and offgassing
, List the signs and symptoms of decompression sickness? -Answer-Excessive fatigue
weakness and tingling in limbs
limb and join pain and dysfunction
skin rashes and itching
vertigo
loss of sensation
Paralysis
Death
What is the primary waster product in metabolism? -Answer-Carbon Dioxide
When do symptoms of hypoxia appear? -Answer-When the partial pressure of
oxygen falls below 0.16 ata
Central nervous system toxicity can result from what? Pulmonary toxicity? -Answer-
Short exposure to high partial pressure of oxygen;
Prolonged exposure to elevated partial pressure of oxygen
The recommended maximum PO2 for enriched air nitrox diving is: -Answer-1.4 ata
What are some of the many factors that can increase your susceptibility to CNS
oxygen toxicity? -Answer-Heavy exercising
Increased carbon dioxide buildup
Chilling
Water immersion
What does the mnemonic acronym "ConVENTID" stand for? -Answer-Convulsions
Visual disturbances
Ears
Nausea
Twitching and tingling
Irritability
Dizziness or dyspnea
What are the two standard nitrox mixes? -Answer-32% and 36% oxygen
What is the Maximum Operating Depth (MOD)? -Answer-The maximum operating
depth that should be dived with a given nitrox mixture
Using the Maximum Operating Depth table, what is the MOD for EAN36 if the PO2 is
not to exceed 1.4 ata? -Answer-28 msw (95 fsw)
What is the first thing you need to find when calculating the maximum operating
depth for any nitrox mixture? -Answer-Find the total pressure that it takes to produce
the maximum acceptable oxygen partial pressure, and then convert it to a depth
What is the range of oxygen percentages you can set on the NAUI mobile App
calculators? -Answer-21%-40%
