ASPE CPD STUDY QUESTIONS AH EXAM WITH VERIFIED
SOLUTIONS A+ SCORE REVIEW
What is the conversion for uniform flow velocity and capacity in
sloping pipe going from from 1/4 in/ft slope to 1/8 in/ft? 1/2 in/ft?
- --Answers----0.707 and 1.414
The hydraulic mean depth of flow or hydraulic radius is what
ratio and what value? - --Answers----The ratio of the cross
sectional area of flow to the wetted perimeter of pipe surface,
expressed as D/4 where D is diameter in feet. It is the same ratio
for full and half flow.
How is the quantity “rate of flow” expressed? - --Answers--
--Cross sectional area of flow times the average velocity.
What formula determines the velocity of uniform flow in sloping
drains? - --Answers----The Manning Formula
Flow in piping and open channels is caused by what? - --
Answers----The gravitational force induced by the slope of the
drain and the height of water in that drain.
How is maximum pressure drop calculated for a medical gas
system? - --Answers----Identify the maximum pressure drop
allowed for the specific gas system, divide it by equivalent length,
and multiply by 100.
In medical gas piping, how is diversity calculated? - --Answers--
--From simultaneous use factors given in a table.
,What are recommended minimum medical gas riser sizes? - --
Answers----Oxygen: 3/4” Medical air: 3/4” Nitrous Oxide:
3/4” Nitrogen: 1” Vacuum: 1”
What are minimum medical gas pipe sizes? - --Answers----Med
gas mains and branches: 1/2” Vacuum mains and branches:
3/4” Drops to individual outlets/inlets: 1/2” Piping to alarm
panels: 1/4”
Where should medical gas piping be labeled? - --Answers----
Every 20 feet, once in each room, at each side of every wall
penetration, and at each floor level, and with the appropriate
color.
What joints are prohibited in medical gas systems? - --Answers-
---Flared or compression type, straight thread connections,
clamp/gasket style couplings, pipe crimping tools, all joints that
do not provide the mechanical, thermal, and sealing integrity of a
brazed joint.
What type of piping material is used for vacuum or WAGD
medical gas? - --Answers----Seamless, hard-drawn type K, L
or M copper tube or stainless steel tube. For level 3 vacuum
systems, schedule 40 wall pvc plastic may be used.
What type of piping material is used for medical air or gases? - -
-Answers----Hard drawn seamless type K or L copper tube,
cleaned and capped for medical services (ASTM B819)
For gas piping, how is probable peak demand calculated? - --
Answers----Identify the number of outlets for the system,
identify the outlet/room flow rate for each specific gas,
determine the simultaneous use factor/diversity percentage
,What are the requirements for medical/surgical vacuum outlets?
- --Answers----Med/surg vacuum outlets should draw 85 LPM
(3 standard cfm) without reducing the vacuum pressure below 12
in Hg at any adjacent outlet
What is the delivery required for oxygen and medical air outlets
serving critical areas? - --Answers----170 liters per minute (6
standard cfm) for a minimum of three seconds
What is the delivery rate, pressure drop, and static pressure for
support outlets? - --Answers----140 liters per minute (5
standard cfm, or scfm) delivery, pressure drop of no more than 5
psi, and a static pressure of 160-185 psig
What is the pressure, delivery rate, pressure drop, and static
pressure for oxygen, nitrous oxide, medical air and carbon
dioxide outlets? - --Answers----50 psig pressure, 100 liters per
minute (3.5 standard cfm, or scfm) delivery, pressure drop of no
more than 5 psi, and a static pressure of 50-55 psig
What shall medical gas valve identification include? - --
Answers----Name of the gas or vacuum system, room or areas
served, a caution to not close or open the valve except in an
emergency
What is a WAGD system? - --Answers----Waste anaesthetic gas
disposal system includes oil-les/inert vacuum producers, and is
required at each anesthetizing location. It is violet colored and
gas specific. The minimum flow/Hg is determined by patient
equipment requirements
, What are the three levels and their ramifications in terms of
potential patient risk if a medical gas system fails? - --Answers-
---Level 1: Places patients in imminent danger of morbidity or
mortality Level 2: Places patients at manageable risk for
morbidity or mortality Level 3: Terminates procedures but would
not place patients at risk of morbidity or mortality
What is the definition of medical gases and can you name the 8
major gases? - --Answers----Gases that are used as part of a
healthcare procedure other than for normal body functions. 1)
Oxygen, 2) Medical Air 3) Nitrous Oxide 4) Carbon dioxide 5)
Nitrogen 6) Instrument Air 7) Vacuum and 8) WAGD
What two methods of gas sizing may be used? - --Answers----1)
The longest length method sizes the main from the meter to the
farthest gas user (stay constant along the maximum horizontal
length). The same maximum length can be used for branches. 2)
The branch length method sizes the branches (not the main)
based on their individual actual lengths from the meter.
What five factors are involved in the sizing of gas systems? - --
Answers----1) Allowable pressure drop from meter to farthest
outlet 2) Demand (load) in (ft^3/h) 3) Actual length of run (see
NFPA 54 National Fuel Gas Code for gas sizing tables) 4) Specific
gravity of gas 5) Diversity factor (or factor of usage) if allowed by
code
What is the testing procedure for the gas piping? - --Answers---
-The entire system should be subjected to an air test for 10 min
at a pressure that is twice the working pressure without showing
any loss of pressure.
SOLUTIONS A+ SCORE REVIEW
What is the conversion for uniform flow velocity and capacity in
sloping pipe going from from 1/4 in/ft slope to 1/8 in/ft? 1/2 in/ft?
- --Answers----0.707 and 1.414
The hydraulic mean depth of flow or hydraulic radius is what
ratio and what value? - --Answers----The ratio of the cross
sectional area of flow to the wetted perimeter of pipe surface,
expressed as D/4 where D is diameter in feet. It is the same ratio
for full and half flow.
How is the quantity “rate of flow” expressed? - --Answers--
--Cross sectional area of flow times the average velocity.
What formula determines the velocity of uniform flow in sloping
drains? - --Answers----The Manning Formula
Flow in piping and open channels is caused by what? - --
Answers----The gravitational force induced by the slope of the
drain and the height of water in that drain.
How is maximum pressure drop calculated for a medical gas
system? - --Answers----Identify the maximum pressure drop
allowed for the specific gas system, divide it by equivalent length,
and multiply by 100.
In medical gas piping, how is diversity calculated? - --Answers--
--From simultaneous use factors given in a table.
,What are recommended minimum medical gas riser sizes? - --
Answers----Oxygen: 3/4” Medical air: 3/4” Nitrous Oxide:
3/4” Nitrogen: 1” Vacuum: 1”
What are minimum medical gas pipe sizes? - --Answers----Med
gas mains and branches: 1/2” Vacuum mains and branches:
3/4” Drops to individual outlets/inlets: 1/2” Piping to alarm
panels: 1/4”
Where should medical gas piping be labeled? - --Answers----
Every 20 feet, once in each room, at each side of every wall
penetration, and at each floor level, and with the appropriate
color.
What joints are prohibited in medical gas systems? - --Answers-
---Flared or compression type, straight thread connections,
clamp/gasket style couplings, pipe crimping tools, all joints that
do not provide the mechanical, thermal, and sealing integrity of a
brazed joint.
What type of piping material is used for vacuum or WAGD
medical gas? - --Answers----Seamless, hard-drawn type K, L
or M copper tube or stainless steel tube. For level 3 vacuum
systems, schedule 40 wall pvc plastic may be used.
What type of piping material is used for medical air or gases? - -
-Answers----Hard drawn seamless type K or L copper tube,
cleaned and capped for medical services (ASTM B819)
For gas piping, how is probable peak demand calculated? - --
Answers----Identify the number of outlets for the system,
identify the outlet/room flow rate for each specific gas,
determine the simultaneous use factor/diversity percentage
,What are the requirements for medical/surgical vacuum outlets?
- --Answers----Med/surg vacuum outlets should draw 85 LPM
(3 standard cfm) without reducing the vacuum pressure below 12
in Hg at any adjacent outlet
What is the delivery required for oxygen and medical air outlets
serving critical areas? - --Answers----170 liters per minute (6
standard cfm) for a minimum of three seconds
What is the delivery rate, pressure drop, and static pressure for
support outlets? - --Answers----140 liters per minute (5
standard cfm, or scfm) delivery, pressure drop of no more than 5
psi, and a static pressure of 160-185 psig
What is the pressure, delivery rate, pressure drop, and static
pressure for oxygen, nitrous oxide, medical air and carbon
dioxide outlets? - --Answers----50 psig pressure, 100 liters per
minute (3.5 standard cfm, or scfm) delivery, pressure drop of no
more than 5 psi, and a static pressure of 50-55 psig
What shall medical gas valve identification include? - --
Answers----Name of the gas or vacuum system, room or areas
served, a caution to not close or open the valve except in an
emergency
What is a WAGD system? - --Answers----Waste anaesthetic gas
disposal system includes oil-les/inert vacuum producers, and is
required at each anesthetizing location. It is violet colored and
gas specific. The minimum flow/Hg is determined by patient
equipment requirements
, What are the three levels and their ramifications in terms of
potential patient risk if a medical gas system fails? - --Answers-
---Level 1: Places patients in imminent danger of morbidity or
mortality Level 2: Places patients at manageable risk for
morbidity or mortality Level 3: Terminates procedures but would
not place patients at risk of morbidity or mortality
What is the definition of medical gases and can you name the 8
major gases? - --Answers----Gases that are used as part of a
healthcare procedure other than for normal body functions. 1)
Oxygen, 2) Medical Air 3) Nitrous Oxide 4) Carbon dioxide 5)
Nitrogen 6) Instrument Air 7) Vacuum and 8) WAGD
What two methods of gas sizing may be used? - --Answers----1)
The longest length method sizes the main from the meter to the
farthest gas user (stay constant along the maximum horizontal
length). The same maximum length can be used for branches. 2)
The branch length method sizes the branches (not the main)
based on their individual actual lengths from the meter.
What five factors are involved in the sizing of gas systems? - --
Answers----1) Allowable pressure drop from meter to farthest
outlet 2) Demand (load) in (ft^3/h) 3) Actual length of run (see
NFPA 54 National Fuel Gas Code for gas sizing tables) 4) Specific
gravity of gas 5) Diversity factor (or factor of usage) if allowed by
code
What is the testing procedure for the gas piping? - --Answers---
-The entire system should be subjected to an air test for 10 min
at a pressure that is twice the working pressure without showing
any loss of pressure.
