Name the three gases categorized as nonflammable
Nitogen, Carbon Dioxide and Helium.
Most therapeutic gases will support combusion. Name three gases in this category.
oxygen, helium/oxygen, nitrous oxide
Describe the four basice step of fractional distillation process.
Atmospheric air is filtered to remove pollutants, water and Co2.
Purified air is then liquefied by compression and cooled by rapid expansion.
Heated in distillation chamber so nitrogen escapes first.
Stored in cryogenic storage in liquid form;
/or convert
What purifty level is required for medical grade oxygen?
99.0%
Used to treat to hiccups.
Carbon Dioxide
The "D" in (DISS) stands for
Diameter
A device that controls both pressure and flow
Regulator
Agency that classifies cylinders
Department Of Transportation. (DOT)
Chemical named for this light gas
HE
This meter controls the volume of gas per unit of volume
Flowmeter
Neddle_______________ adjust the flow in a Thorpe tube
Valves
Type of "distillation" that produces oxygen
Fractional
Gas used in treatment of severe asthma
Heliox
Valve that lowers gas pressure
Reducing valve
Low density gas
Helium
DISS (Diameter-Index Safety System)
*Low pressure safety system
Found at outlets of pressure-reducing valves , outlets of central piping systems, &
inlets of blenders, flowmeters, vents.
Pipe with many connections used to link gas cylinders together
Manifold
Gas delivered in a yellow cylinder
Air
This valve shut off the gas in case of a fire
Zone
PISS (Pin-Index Safety System)
*Your mom told you not to say this, but it really is a safety system.
*For small cylinders (up to & including size E) & their attachments
*Cylinders have yoke type connection
*Exact positions of pins & pinholes vary for each gas
**2 - 5 for oxygen
**1 - 5
Gas delivered in a blue cylinder
Nitrous Oxide or
The "P" in PISS means
Pin
Gas that makes up 20.95% or 21% of air
Oxygen
Fixed open, variable pressure measuring or mettering device. Also it is most appropriate for transport.-
Bourdon Gauge
Rear end: also a safety system
ASSS (American standard safety system)
Just say "NO
Nitric Oxide
Agency that sets standards for gas purity
FDA
Sets standards for design, construction, placement and use of bulk oxygen system
NFPA
Gas with only one oxygen molecule
Oxide
Slang term for cylinder
Tank
second half of gas made by heating limestone in contact with water
Dioxide
Name the two method of seperating oxygen from air and what concentration is produced.
a. Molecular device-90%
b. Vaccum -40%
what device is used to produce medical grade air for hospital and home?
Hospital-Air copressor system
Home-oxygen concentrator
Most medical grade carbon dioxide is used for what purpose?
Diagnostic purpuse
What is Heliox and what is it used for?
gas mixed oxygen and helium and use for severe airway obtructions
what is the primany medical use for nitrous oxide.
Use as an anesthetic agent
Describe two hazards of using nitric oxide
1. Can cause chemical pneumonitis and
exposeure to high concentration of nitric oxide 2. can cause methemoglobinemia.
Give the chemical symbol for each of the following:
Oxygen
Air
Carbon Dioxide
Helium
Nitrous Oxide
Nitric Oxide
O2
Air
CO2
He
N2O
NO
Because cylinder color is only a guideline, how do you actually determine what gas is in a tank?
careful inspection of label.
What is the best way to determine the actual oxygen concentration in a cylinder?
Analyze gas before administrating it.
Name two gases that can be stored in the liquid state at room temperature.
CO2 and N2O
Explain why the pressure in a gas-filled cylinder is different than of a liquid-filled cylinder.
Gas is compressed into the cylinder to fill it whereas , liquid is filled to specific level and gas is released from the liquid to pressurize the tank.
Describe the methods for measuring the contents of a gas-filled and the liquid-filled cylinder.
(a) Gas is directly proportional to it volume of pressure which can be read by a guage to read it's pressure.
(b) The measuered pressure is the vapor pressure above the liquid. This pressure bears no relation to the amount of liquid remaining.
Write the formular for calculating the cylinder factor for a gas-filled cylinder.
cubic feet (filled cylinder) x 28.3/
(pa) Pressure (filled cylinder) in psig
What are the cylinder factor for "E" and "K
E" =.28
K/H=3.14
Write the fourmula for caluclating duration of flow in minute.
duration of flow=contents/flow
Describe a gasous bulk system. Be sure to discuss the manifold, the primary, and reserve banks.
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 a gas pressure. It is then decreased by regulators to 50psi whichi is then send into the hospital
Why do most hospitals use a liquid oxygen system?
It is economical, safe and conveience
Where are the small liquid oxygen cylinders usually used?
They are used for home O2 supply
What is the critical temperature of oxygen? How is is the bulk liquid maintained at this temperature?
-118.6C. Tanks has an inner and outer shell with insulation between the shell.
What is the normal working pressure for a hospital oxygen piping system?
50psi
What are the zone valves? Give two reasons you might neeed to use these valves.
Zone valves are valves that shut off the sections of the hospital.
a. fire; b. maintenance
Gas laws states; If a cylinder overheat, the pressure will rise. Describe the type of pressure release valve usually found in these cylinder sterm.
Small cylinder-fusible plug relief valve
Large cylinder-spring loaded relief valve
Name the three basic indexed safety system for medical gas.
(both names- the abbreviation and meaning.
a. ASSS (American standard safety system)
b.DISS (Diameter-Index Safety System)
c .PISS (Pin-Index Safety System)
A large cylinder of O2 is describe as follows: CGA-540 0903-14NGO-RH Ext. Explain what this means.
CGA connection thread and number540 0.903 thread diameter of outlet -14 thread per sq in RH right hand thread
What tpye of cylinder uses pins and holes for the safety connection system?
Small cylinder.
What system was established to prevent accidental interchange of low-pressure medical gas connectors?
Diameter Index Safety System [DISS]
What is the purpose of the quick-connect system.
Allow quick access to a bulk supply of O2
Describe the action of the following devices.
Reducing Valve
Flowmeter
Regulator
Reducing valve-reduction of gas pressure
Flowmeter- control gas flow to patient
Regulator-control pressure and flow of gas
Describe the normal way the preset reducing valve is used in respiratory care.
Preset to only give out the amount of pressure set by manifold
Describe the normal way the Adjustable reducing valve is used in respiratory care.
used on high pressure system to regulator from high to low presure to sytem.
Describe the normal way multiple-stage reducing valve is used in respiratory care.
Reducing high pressure in multiple stage.
What two hazards can be created when you open a cylinder attached ot a high pressure reducing valve?
gas undergo rapid decompression followed by recompression.
Two advantages of flow restrictors.
a. Low cost; can be
b. Can be used in any postion
Two disadvantages of flow restrictors.
a. accuracy varies
b. can not be used with high- resistance equipments
What is the cheif advantage of the Bourdon-type flowmeter?
Operates under variable pressures.
How will indicated flow campare to actual flow when a Bourdon flowmeter meets up with downstream resistance?
Bourdon will read higher pressure than the actual flow reading
What is Bourdon gauges and what does it actually measure?
*Always used in combination with adjustable pressure-reducing valve
*Uses fixed open but operates under variable pressures
*Not gravity dependent; ideal for patient transport
*Not accurate when pressure distal to orifice changes.
It measures pressure of a
What does Thorpe tube actually measure?
It measures true flow of oxygen.
What happened to the flow in a compensated Thorpe tube when you connect to a 50 psi gas source?
it jumps and returns to zero as the Thorpe tube is pressurized.
What are the characteristics of Oxygen? (O2)
*Colorless, odorless, transparent, & tasteless
*Has density of 1.429 g/L
*3.3 ml of O2 dissolves in 100 ml of water
*Nonflammable but greatly accelerates combustion
*Oxygen concentrators pull ambient air through semipermeable plastic membrane
What are the characteristics of Air?
*Colorless, odorless.
*21% oxygen, 78% Nitrogen, 1% trace gases
*Medical grade air is produced by filtering cooling and compressing ATM air.
*Must be dry, pollutant and free of oil
*Has density of 1.29 g/L.
What are the characteristics of Carbon Dioxide? (CO2)
*Colorless & odorless gas
*Does not support combustion
*Usually is produced by heating limestone in Common uses for CO2 mixtures
***Calibration of blood gas analyzers
***Diagnostic purposes in clinical laboratory
Mixtures of O2 & 5-10% CO2 have therapeuti
What are the characteristics of Helium? (He)
*Odorless, tasteless, nonflammable, & chemically & physiologically inert
*Has density of 0.1785 g/L; much less than air
*Commercially produced from natural gas through liquefaction to purity standards of at least 99%
*Must always be mixed with at least 20
What are the characteristics of Nitric Oxide? (NO)
*Colorless, nonflammable, toxic gas that
supports combustion
*Exposure to high concentrations alone can
cause methemoglobinemia, which can cause
tissue hypoxia
*FDA approved for use in treatment of term &
near-term infants with hypoxic respiratory
failure
What are the differences between gas-filled cylinders and liquid-filled cylinders?
In a gas-filled cylinders the volume of gas in cylinder is directly proportional to its pressure, whereas with the liquid-filled cylinders, the pressure does not relate to amount of liquid remaining and only weight of cylinder indicates amount of gas insi
Write the formular for calculating the duration of flow. Content/flow?
Pressure (psig) x Cylinder factor / Flow (L/min
Alternating supply system or cylinder manifold system. (A type of Bulk O2 supply system)
*Consists of large (normally H or K size) cylinders of compressed O2 banked together in series
*When pressure in primary bank decreases to set level, control valve automatically switches over to reserve bank.
Cylinder supply system with reserve supply.
(A type of Bulk O2 supply system)
*Consists of primary supply, secondary supply, & reserve supply
*When primary gas supply is depleted by demand, this supply system automatically switches to secondary supply.
Bulk gas system with reserve.
*Most commonly used in large health facilities for economical, safety, & convenience reasons
*Small volume of liquid O2 provides very large amount of gaseous O2 & minimizes space requirements.
NFPA standards:
1. Must be stored 50 feet from wood frame
buildings.
2. Must be 25-50 feet from the hospital.
3. Must be fenced.
4. Must have a reserve backup.
5. Must have safety release valves.
American Standard Safety System (ASSS)
*For large cylinders & their attachments
*Prevents accidental misconnections
Three ways to tell a compensated flowmeter:
1. look at label. Calib at 50 psig
2. Ball jump
3. Position of needle valve.
Reducing valve
is used to reduce gas pressure to useable level
Flowmeter
is used to control flow to patient
Regulator
s used to control both pressure & flow
3A
Cylinder made of carbon steel
3AA
containers are manufactured with alloy steel