Medical Gas Production/storage

Given the following gas mixture and total pressure, calculate the partial pressure for oxygen: Oxygen10% Carbon dioxide20% Nitrogen70% Total pressure760 mmHg

76.0 mmHg

One cu/ft of liquid O2 is the equivalent of about how many cu/ft of gaseous O2?

860

What is the Food and Drug Administration (FDA) purity standard for O2?

99%

You are preparing to conduct a complex transport of a patient receiving O2, and you expect to have to alter O2 flows during the transport. Which of the following devices would best meet your needs?

Bourdon gauge

What safety system is designed to prevent accidental interchanging among low-pressure (< 200 psig) connectors such as those found on flowmeters and ventilators?

DISS

When used to control the flow of medical gases to a patient, how is a flow restrictor classified?

Fixed orifice, constant-pressure flowmetering device

When used to control the flow of medical gases to a patient, how is a Bourdon gauge classified?

Fixed orifice, variable-pressure flowmetering device

Why are zone valves incorporated into a hospital's central gas piping systems? I. To terminate O2 delivery to an area in case of fire .II. To allow selective maintenance without shutting the system down .III. To allow variable pressure reduction throughout the system.

I and II

Station outlets may consist of:I. Diameter Index Safety System (DISS) fittingsII. American Standard Safety System (ASSS) fittingsIII. quick connect fittings

I and III

Under which of the following circumstances will gas flow be greater between two points? I. if the pressure difference is large II. if the pressure difference is small III. if the opening between the points is large IV. if the opening between the points is small

I and III

Under which of the following circumstances will gas flow be greater between two points?I. if the pressure difference is largeII. if the pressure difference is smallIII. if the opening between the points is largeIV. if the opening between the points is small

I and III

Which of the following medical gases can be stored in cylinders as liquids at room temperature? I. CO2II. O2III. N2O

I and III only

Which of the following are safety features of cylinder valves?I. American Standard Safety System threadingII. pin index safety system connectionsIII. fusible plugsIV. frangible disks

I, II, III,IV

Air for medical use in a hospital should be which of the following? I. Particle-freeII. Oil-freeIII. Dry

I,II and III

The diameter index safety system (DISS):I. uses different pitches and threads per inchII. uses internal and external threadsIII. is intended for low pressure (< 200 psi)IV. is intended for high pressure (> 200 psi)

I,II and III

the diameter index safety system (DISS):I. uses different pitches and threads per inchII. uses internal and external threadsIII. is intended for low pressure (< 200 psi)IV. is intended for high pressure (> 200 psi)

I,II, and III

Which of the following should be observed when storing cylinders?I. Post the names of gases being stored.II. Keep empty and full cylinders separate.III. Use chains to secure the cylinders to the wall.IV. Do not store flammable substances with the cylinders.

I,II,III, IV

What do the components of a liquid O2 bulk storage tank include? I. Inner and outer steel shells, separated by a vacuum II. A safety system that vents O2 if warming occurs III. A vaporizer system that converts liquid O2 to gas IV. Pressure-reducing valves to lower pressure to 50 psig

I,II,III, and IV

What factors should you consider when placing an oxygen concentrator into a patient's home? I. Know how large of an electrical load is allowed on the circuit you wish to use. II. Keep the concentrator away from loose draperies. III. Keep the concentrator away from heat vents, registers, or baseboard heaters. IV. Place the concentrator centrally within the home if possible.

I,II,III, and IV

Which of the following should be observed when storing cylinders? I. Post the names of gases being stored. II. Keep empty and full cylinders separate. III. Use chains to secure the cylinders to the wall. IV. Do not store flammable substances with the cylinders.

I,II,III, and IV

What do the components of a liquid O2 bulk storage tank include? I. Inner and outer steel shells, separated by a vacuumII. A safety system that vents O2 if warming occursIII. A vaporizer system that converts liquid O2 to gasIV. Pressure-reducing valves to lower pressure to 50 psig

I,II,III,and IV

Which of the following should be observed when moving an "H" cylinder of oxygen? I. Leave the valve cap on. II. Don't lift the cylinder by its cap. III. Don't slide or drag the cylinder. IV. Don't drop the cylinder.

I,II,III,and IV

Which of the following are true regarding a compensated Thorpe tube flowmeter? I. The needle valve is proximal to the Thorpe tube. II. The needle valve is distal to the Thorpe tube. III. The flowmeter reads accurately in the presence of back pressure. IV. The flowmeter reads higher in the presence of back pressure.

II and III

Which of the following are true regarding a compensated Thorpe tube flowmeter?I. The needle valve is proximal to the Thorpe tube.II. The needle valve is distal to the Thorpe tube.III. The flowmeter reads accurately in the presence of back pressure.IV. The flowmeter reads higher in the presence of back pressure.

II and III

Compared to portable cylinders, a centrally located, piped-in bulk O2 system has which of the following advantages? I. No need for a backup or reserve system II. More convenient and less hazardous than cylinders III. O2 is already reduced to its working pressure IV. Less risk of the O2 supply being depleted

II,III, and IV

During inspection of the shoulder of a compressed gas cylinder, you note a plus sign (+) next to the test date. This indicates what about the cylinder?

It only requires a 10 year DOT inspection and can be filled to 10% above its service pressure.

Which of the following is false about a Bourdon gauge?

It will register zero flow when the outlet is completely blocked.

an oxygen concentrator works using the principle of

absorption

When using a Bourdon gauge flowmeter, it is important to:

be certain all tubing is free of kinks or obstructions

the riser valve controls oxygen flow

between floors

The most common application of the adjustable pressure reducing valve is in combination with which of the following?

bourdon gauge

How can one determine whether a pressure-reducing valve uses multiple stages for pressure reduction?

by netting the number of pressure relief vents

By what means is air for medical use in a hospital most commonly produced?

compression of atmospheric air

a hydrostatic test

determines the integrity of the cylinder

What is the only major factor limiting the use of pressure-compensated Thorpe tube flowmeters?

effect of postion(gravity)

When using a Bourdon gauge against high outflow resistance, what will the flowmeter reading show?

exceed actual flow

What is the most common and least expensive method for commercial production of O2?

fractional distillation of air

What is the greatest potential problem with quick-connect DISS systems (such as Ohio, NCG, or Puritan)?

incompatibility among different manufacturers

Which of the following statements about CO2 is false?

it is a flammable gas

Which of the following statements about He is false?

it is heavier than air

What key property of He makes it useful as a therapeutic gas?

low density

According to the U.S. Department of Commerce, a gas cylinder that is color coded blue should contain which of the following?

n20

What is the fire-risk classification of both N2 and CO2?

nonflammable

According to the National Institute of Standards and Technology of the U.S. Department of Commerce, a gas cylinder that is color-coded brown and green should contain which of the following?

o2-He mixture

Gas flows from one point to another because:

of pressure gradient

Which of the following methods of producing O2 is commonly used in the home care setting?

physical separation

Which of the following mechanisms do all compressed gas cylinders use to avoid excessively high buildup of cylinder pressure?

pressure-relief valve on the valve stem

To clean a cylinder valve outlet of foreign material, what should you do?

quickly open, then close, the valve

In the presence of back pressure, a Bourdon gauge flowmeter will:

read higher than the actual flow delivered

What is the usual method of monitoring the remaining contents in a gas-filled cylinder?

read the pressure gauge

If you had to power a ventilator from a large cylinder of compressed gas, which of the following devices would be required?

reducing valve

A flowmeter attached to a reducing valve is known as a:

regulator

What device is used to reduce the pressure and control the flow of a compressed medical gas?

regulator

Compressed gas cylinders are manufactured from which of the following?

seamless steel

What is the key difference between small compressed gas cylinders (sizes AA to E) and their larger counterparts (sizes F to K)?

small gas cylinders use a yoke ( not threaded) connector

Upon inspection you note the letter and number combination of 3AA stamped into an oxygen cylinder's shoulder. This means:

the cylinder is made of chrome molybdenum steel

To what is the measured pressure in a gas-filled cylinder equivalent?

the force required to compress its volume within the cylinder

Fixed orifice flowmeters operate by:

the pressure set proximal to the orifice determining gas flow

You need to transport a patient by helicopter to your home base one and one-half hours away. You are using a bag-mask at a liter flow of 15 L/min. How many full "E" cylinders do you need for the transport?

three

To accurately determine the remaining contents of a liquid-filled CO2 cylinder, what would you do?

weigh the contents of the cylinder

You are working with an outpatient who needs to go home on an "E" cylinder. She is wearing a nasal cannula at 2 L/min, and her cylinder has 1,500 psi remaining. She needs to travel by car one and one-half hours to reach her home and her concentrator. Can she make it?

yes

The gauge on an H cylinder of O2 reads 2000 psig. About how long would the contents of this cylinder last, until completely empty, at a flow of 6 L/min?

17 hours, 30 minutes

You are about to transport a patient from computerized tomography (CT) to the intensive care unit who is being bagged with a bag-mask. You set the liter flow at 15 Lmin. The cylinder reads 1,000 psi. How long do you have before the cylinder is empty?

18 minutes

You are planning a patient transport that will take about 1-1/2 hours. The patient requires manual ventilation with 10 L/min of O2. What is the minimum number of full E cylinders you would take with you?

2

What is the PISS index hole position for O2?

2 and 5

You are determining the weight of a portable reservoir, and you determine that it contains 10 lbs of liquid oxygen. This is equivalent to:

3,440 L of gaseous oxygen

What cylinder factor is used to compute the duration of flow for a 244 cu/ft (H/K) O2 or air cylinder?

3.14

A cylinder of N2O has a gauge pressure of 750 psig when full. What will be the pressure in this cylinder when it is half full?

375 psig

Department of Transportation (DOT) regulations require compressed gas cylinders to be hydrostatically tested for leaks and expansion every how often?

5-10 years

The pressure of O2 or air in a bulk supply system is reduced to what standard working pressure?

50 psig

You are setting a patient up on a non-rebreathing mask at a liter flow of 10 L/min. The "H" cylinder you are using reads 1,700 psi. How long will the cylinder last until you need to change it at 500 psi?

6 hours

What cylinder factor is used to compute the duration of flow for a 22 cu/ft O2 or air E cylinder?

0.28

Advantages of a Bourdon gauge flowmeter include which of the following?I. It is very compact.II. It works in any position.III. It is accurate in the presence of back pressure.IV. It is back-pressure compensated.

1 and II

The gauge on an E cylinder of O2 reads 800 psig. About how long would the contents of this cylinder last, until completely empty, at a flow of 3 L/min?

1 hour, 15 minutes

When full, a gas cylinder registers a pressure of 2200 psig. After a few hours of use, the pressure gauge reads 550 psig. The cylinder is now how full?

1/4

Given the following gas mixture and total pressure, calculate the partial pressure for carbon dioxide: Oxygen10% Carbon dioxide20% Nitrogen70% Total pressure760 mmHg

152.0 mmHg

The atmospheric pressure is 740 mmHg (Salt Lake City, UT). What is the partial pressure for oxygen?

155 mmHg

What is the indexed safety system for threaded high-pressure connections between large compressed gas cylinders and their attachments?

American standard safety system (ASSS)

When minimal fluctuations in pressure and flow are critical factors, which of the following pressure-reducing valves would be the best choice?

Multiple-stage pressure-reducing valve

Structural requirements for the central piping systems that are used in hospitals to distribute gases are established by whom?

NFPA

Which of the following gases is used to treat conditions causing hypoxic respiratory failure?

O2

Unlike CO2 or N2O, O2 cannot be stored as a liquid at room temperature but must be kept in special cryogenic containers. Why is this so?

O2 has a critical temperature well below room temperature.

What is the primary purpose of indexed connector systems?

Prevent inadvertent misconnections between equipment

In clinical practice, how is a positive identification made of the contents of a medical gas cylinder?

Reading the cylinder label, ID the color of the cylinder

Which of the following statements is false about PISS standards?

They apply to low-pressure (<200 psig) connections.

If you have to deliver O2 to a patient directly from a bedside outlet station, which of the following devices would you select?

Thrope tube flowmeter

When used to control the flow of medical gases to a patient, how is a Thorpe tube classified?

Variable orifice, constant-pressure flowmetering device