STORAGE AND DELIVERY OF MEDICAL
GASES EXAM QUESTIONS AND
ANSWERS 100% CORRECT
Non flammable - ANSWER-Unable to support combustion
Oxidizing - ANSWER-Not flammable but supports combustion
Bourdon gauge - ANSWER-A fixed orifice comma variable pressure flow meter
Thorpe tube - ANSWER-A variable orifice, constant pressure flow meter
Reducing valve - ANSWER-A valve that reduces gas pressure
Regulator - ANSWER-A device that controls both pressure and Flow
Flow meter - ANSWER-A device operated by a needle valve that controls or measures
gas flow according to viscosity and density
Zone valve - ANSWER-On and off piping valve that controls medical Gas Distribution to
pre-specified zones of the hospital
List three gases that are categorized as non flammable - ANSWER-Nitrogen, helium,
and carbon dioxide
Most therapeutic gases will oxidize or support combustion. List three gases in this
category. - ANSWER-Air, oxygen, and nitric oxide
Describe the four basic steps of the fractional distillation process - ANSWER-
Atmospheric air is filtered to remove pollutants, water, and carbon dioxide.
Purified air is liquefied by compression and cooled by rapid expansion.
The remaining mixture of liquid oxygen and nitrogen is heated slowly in the distillation
tower and repeated twice. The remaining liquid oxygen is transferred to specifically
insulated cryogenic storage cylinders.
What Purity level is required for medical-grade oxygen? - ANSWER-99%
Describe the two methods used to separate oxygen from Air. What concentration is
produced by each method? - ANSWER-A. Inorganic sodium aluminum silicate pellets
absorb nitrogen and water vapor producing 90% oxygen.
B. Pulling of ambient air through a membrane and allows oxygen and water to pass at a
faster rate than nitrogen in ambient air.
, What is the most common use of CO2 mixtures? - ANSWER-It is used for the
calibration of blood gas analyzers and for Diagnostic purposes in Clinical Laboratory
settings
Explain why the pressure in a gas-filled cylinder is different from that of a liquid-filled
cylinder - ANSWER-Pressure in a cylinder depends on its contents. In a gas-filled
cylinder, the pressure represents the force required to compress the gas into its smaller
volume whereas the pressure and a liquid-filled cylinder is the vapor pressure needed to
keep the gas liquefied at current temperature.
Describe the methods for using the contents of a gas-filled cylinder and a liquid-filled
cylinder - ANSWER-A. Gas filled: the volume of gas is directly proportional to pressure
at constant temperature
B. Liquid filled: the measured pressure is the vapor pressure above the liquid
What are the cylinder factors for the E, G, and H gas field oxygen cylinders? -
ANSWER-E- 0.28
G- 2.41
H- 3.14
Write the formula for calculating duration of flow in minutes of gas filled cylinders. -
ANSWER-Duration of flow (min) = (pressure x cylinder factor) / (flow rate)
Describe a gaseous bulk systems. Be sure to discuss the manifold, the primary, and
Reserve Banks. - ANSWER-Oxygen is stored in a large tank at low pressure, as the
liquid flows through, it is heated up. The liquid is then converted back to gas pressure. It
is then decreased by Regulators to 50 psi which is then sent to the hospital.
What is heliox? What is it used for in the clinical setting? - ANSWER-Heliox is a gas
mixture of oxygen and helium and may be used clinically to manage severe cases of
Airway obstruction. Example: life threatening asthma
What is the primary medical use for nitrous oxide? What are some of the hazards of
nitrous oxide Administration? - ANSWER-Nitrous oxide is clinically used as an
anesthetic agent. Hazards consist of the president of the central nervous system,
increased risk for fetal disorders, and spontaneous abortion.
Describe two possible hazards for using nitric oxide - ANSWER-A. Exposure to high
concentration of NO can cause methmoglobinemia which could lead to tissue hypoxia
B. Use of inhaled NO in treatment of premature neonates with hypoxic respiratory
failure does not improve outcomes and may increase the risk for intracranial
hemorrhage
GASES EXAM QUESTIONS AND
ANSWERS 100% CORRECT
Non flammable - ANSWER-Unable to support combustion
Oxidizing - ANSWER-Not flammable but supports combustion
Bourdon gauge - ANSWER-A fixed orifice comma variable pressure flow meter
Thorpe tube - ANSWER-A variable orifice, constant pressure flow meter
Reducing valve - ANSWER-A valve that reduces gas pressure
Regulator - ANSWER-A device that controls both pressure and Flow
Flow meter - ANSWER-A device operated by a needle valve that controls or measures
gas flow according to viscosity and density
Zone valve - ANSWER-On and off piping valve that controls medical Gas Distribution to
pre-specified zones of the hospital
List three gases that are categorized as non flammable - ANSWER-Nitrogen, helium,
and carbon dioxide
Most therapeutic gases will oxidize or support combustion. List three gases in this
category. - ANSWER-Air, oxygen, and nitric oxide
Describe the four basic steps of the fractional distillation process - ANSWER-
Atmospheric air is filtered to remove pollutants, water, and carbon dioxide.
Purified air is liquefied by compression and cooled by rapid expansion.
The remaining mixture of liquid oxygen and nitrogen is heated slowly in the distillation
tower and repeated twice. The remaining liquid oxygen is transferred to specifically
insulated cryogenic storage cylinders.
What Purity level is required for medical-grade oxygen? - ANSWER-99%
Describe the two methods used to separate oxygen from Air. What concentration is
produced by each method? - ANSWER-A. Inorganic sodium aluminum silicate pellets
absorb nitrogen and water vapor producing 90% oxygen.
B. Pulling of ambient air through a membrane and allows oxygen and water to pass at a
faster rate than nitrogen in ambient air.
, What is the most common use of CO2 mixtures? - ANSWER-It is used for the
calibration of blood gas analyzers and for Diagnostic purposes in Clinical Laboratory
settings
Explain why the pressure in a gas-filled cylinder is different from that of a liquid-filled
cylinder - ANSWER-Pressure in a cylinder depends on its contents. In a gas-filled
cylinder, the pressure represents the force required to compress the gas into its smaller
volume whereas the pressure and a liquid-filled cylinder is the vapor pressure needed to
keep the gas liquefied at current temperature.
Describe the methods for using the contents of a gas-filled cylinder and a liquid-filled
cylinder - ANSWER-A. Gas filled: the volume of gas is directly proportional to pressure
at constant temperature
B. Liquid filled: the measured pressure is the vapor pressure above the liquid
What are the cylinder factors for the E, G, and H gas field oxygen cylinders? -
ANSWER-E- 0.28
G- 2.41
H- 3.14
Write the formula for calculating duration of flow in minutes of gas filled cylinders. -
ANSWER-Duration of flow (min) = (pressure x cylinder factor) / (flow rate)
Describe a gaseous bulk systems. Be sure to discuss the manifold, the primary, and
Reserve Banks. - ANSWER-Oxygen is stored in a large tank at low pressure, as the
liquid flows through, it is heated up. The liquid is then converted back to gas pressure. It
is then decreased by Regulators to 50 psi which is then sent to the hospital.
What is heliox? What is it used for in the clinical setting? - ANSWER-Heliox is a gas
mixture of oxygen and helium and may be used clinically to manage severe cases of
Airway obstruction. Example: life threatening asthma
What is the primary medical use for nitrous oxide? What are some of the hazards of
nitrous oxide Administration? - ANSWER-Nitrous oxide is clinically used as an
anesthetic agent. Hazards consist of the president of the central nervous system,
increased risk for fetal disorders, and spontaneous abortion.
Describe two possible hazards for using nitric oxide - ANSWER-A. Exposure to high
concentration of NO can cause methmoglobinemia which could lead to tissue hypoxia
B. Use of inhaled NO in treatment of premature neonates with hypoxic respiratory
failure does not improve outcomes and may increase the risk for intracranial
hemorrhage
