ASPE CPD Study Questions AH with
complete solutions.
Front - correct answer. Back
What is the specific weight of water? - correct answer. 62.4 lbs per cubic foot
What happens in a storm and sanitary system after it passes the water
test? - correct answer. A smoke pressure test is recommended with a
smoke pressure of 1 in wc to prove the system gas tight.
Is an air test acceptable for a storm and sanitary system? - correct answer.
Yes, if a water test is not possible, at a pressure of 5 psi, are tests are
impractical and costly
What are the testing procedures for the storm and sanitary system? -
correct answer. A water test upon completion of the rough piping and prior
to concealment of 10 ft wc minimum (except the topmost 10 feet of pipe),
not to exceed 100 ft wc. If system is higher than 100 feet, test plugs must
be installed to facilitate testing, rarely are more than 7 stories tested at
one time. A peppermint oil test may also be done with 2 oz of peppermint
oil and 10 qt boiling water, and searching for peppermint smell at leaks,
however it is difficult to pinpoint the leak by this method
The maximum length from the vent connection to any future drain outlet is
required by code, why, how long is the distance (listed in the book), and
what’s the exception? - correct answer. To prevent a dead end where
slime, sludge and fungi can grow, 2 feet, unless the piping must be extended
to an accessible location for a cleanout
A sanitary tee may be used in the vertical but what may not be used in the
vertical and why? - correct answer. A double sanitary tee because the
possibility of flow crossover
,and excessive pressures when one branch is discharging and the other
isn’t are possible
What are the slopes of pipe inside the building that correspond to 2 fps
velocity? - correct answer. 1/4 in per foot for 3 in and smaller 1/8 in per foot
for larger pipe all elbows, taps, tees etc are tapped at a pitch of 1/4” per
foot
Where should cleanouts be provided? - correct answer. 1) Inside or outside
the building at the point of exit (use a wye branch) 2) at every change in
direction greater than 45 degrees 3) every 50 feet for piping 4” and less,
and 100 ft for larger piping 4) underground piping larger than 10 in should
be provided with manholes at every change in direction and every 150 feet
5) at the base of all stacks 6) as required by code
What size cleanouts are provided in piping? - correct answer. Piping up to 4
inches, the cleanout is the same size as the pipe. Piping greater than 4
inches, 4 inch cleanouts are adequate.
What should be installed in the house drain if there is a danger of backflow
of sewage into the building? Whats the difference? - correct answer. A
backwater valve or a combination BWV with manually operated gate valve.
The BWV does not interfere with the airflow throughout the system, and the
gate valve is recommended where there is a history of backflow as a positive
means of protection.
Branch connections to the house drain should be made where and why? -
correct answer. At the upper portion of the pipe (above the 1/2 - 2/3 full
mark) because: 1) there is a lower chance of stoppages in the branch 2)
there is less flow interference at the point of connection 3) When there is no
flow in the branch, the full area of the pipe is available to relieve pneumatic
pressure fluctuations in the house drain
How many fixture units are equivalent to 1 gpm continuous or
semicontinuous flow and what are examples of these types of flow? - correct
answer. 2 FUs, sump pumps, ejectors, air conditioning equipment, water
cooled, equipment, etc
What minimum slopes are required for building drains and why? - correct
answer. 3 in pipe and smaller: 1/4 in/ft 4-6 in pipe: 1/8 in/ft 8 in pipe and
larger: 1/16 in/ft to maintain 2 fps scouring action if low flow fixtures are
present, 1/4 in/ft for all is a good idea
House drains are designed to flow how full? - correct answer. 1/2 full to 3/4
full max under uniform flow conditions
What is a house (building) drain? - correct answer. The lowest piping of a
gravity drainage system that receives the discharge from soil, waste, and
other drainage pipes inside the building that extends a short distance from
the building and conveys the drainage to the building sewer
,What 3is 3the 3measurement 3from 3horizontal 3that 3separates 3horizontal 3and
3vertical 3drainage 3stacks? 3- 3 correct 3answer. 3 45 3degrees
Does 3an 3interior 3drainage 3stack 3that 3offsets 345 3degrees 3or 3less 3from 3the
3vertical 3require 3a 3change 3in 3size? 3- 3 correct 3answer. 3 No. 3Any 3more 3than 3a
345 3degree 3offset 3requires 3sizing 3the 3offset 3as 3a 3house 3drain.
What 3is 3a 3branch 3interval? 3- 3 correct 3answer. 3 A 3building 3story 3or 3a 3distance
3between 3two 3branch 3connections 3greater 3than 38 3feet 3apart.
Describe 3the 3procedure 3for 3sizing 3interior 3drainage 3stacks. 3- 3 correct
3answer. 3 1) 3First 3size 3the 3horizontal 3branches 3connecting 3to 3the 3stack 32)
3Determine 3the 3minimum 3size 3that 3will 3accept 3each 3branch 3at 3one 3branch
3interval 33) 3Total 3all 3fixture 3units 3connected 3to 3the 3stack, 3and 3determine
3the 3size. 3The 3minimum 3size 3must 3be 3at 3least 3equal 3to 3the 3largest 3diameter
3required 3at 3the 3base. 3You 3may 3reduce 3in 3size 3at 3upper 3branch 3intervals,
3but 3never 3by 3more 3than 31/2 3the 3largest 3size.
What 3is 3the 3total 3recommended 3maximum 3permissible 3flow 3in 3a 3stack? 3-
3 correct 3answer. 37/24 3of 3the 3total 3cross 3sectional 3area 3of 3the 3stack.
Where 3should 3and 3shouldn’t 3you 3connect 3branch 3connections 3to 3stack
3offsets? 3- 3correct 3answer. 3 Not 3to 3the 3horizontal 3offset 3to 3the 3stack 3if 3at 3all
3possible, 3unless 3its 3at 3least 310 3pipe 3diameters 3downstream, 3and 3ideally 32
3feet 3above 3the 3offset 3or 32 3feet 3below 3to 3avoid 3pressure 3fluctuations.
What 3can 3minimize 3hydraulic 3jump? 3- 3 correct 3answer. 3 Increasing 3the 3slope
3of 3the 3horizontal 3drain. 3Connecting 3to 3a 3horizontal 3drain 3that 3is 3larger 3than
3the 3stack.
Any 3offset 3of 3the 3stack 3greater 3than 3what 3can 3cause 3hydraulic 3jump? 3-
3 correct 3answer. 345 3degrees
When 3does 3terminal 3velocity 3occur 3in 3a 3drainage 3stack? 3- 3 correct 3answer. 3 It
3is 3achieved 3at 3approximately 310 3- 315 3fps 3and 3this 3velocity 3is 3achieved
3within 310 3- 315 3feet 3of 3fall 3from 3the 3point 3of 3entry.
A 3drainage 3stack 3should 3never 3be 3designed 3for 3a 3capacity 3greater 3than
3what 3and 3why? 3- 3correct 3answer. 3 One-thrid 3full, 3because 3the 3pressure
3fluctuations 3in 3the 3system 3could 3greatly 3exceed 3the 3maximum 31 3in 3water
3column 3criterion 3and 3lose 3their 3seal 3by 3siphonage 3blowout
What 3is 3one 3positive 3and 3one 3negative 3of 3a 3tee-wye 3fitting? 3- 3 correct
3answer. 3 The 3long 3radius 3tee-wye 3fitting 3gives 3the 3water 3a 3greater
3downward 3component 3than 3a 3sanitary 3tee, 3but 3also 3has 3a 3greater
3probability 3of 3siphoning 3the 3traps
How 3are 3horizontal 3branch 3connections 3to 3the 3stack 3made? 3- 3 correct
3answer. 3 With 3a 3sanitary 3tee 3(a 3short 3radius 3tee-wye, 3vertical 3position 3only)
3or 3with 3a 3long 3radius 3tee-wye
, (vertical 3or 3horizontal 3position). 3(The 3tee-wye 3is 3also 3called 3a 3combination 3wye
3and 3one- 3eighth 3bend)
What 3is 3the 3difference 3between 3soil 3stacks 3and 3waste 3stacks? 3- 3 correct
3answer. 3 Soil 3stacks 3collect 3wastes 3that 3contain 3fecal 3matter, 3and 3waste
3stacks 3collect 3wastes 3that 3do 3not 3contain 3fecal 3matter 3(lavatories, 3sinks,
3etc)
What 3is 3a 3vent 3stack? 3- 3 correct 3answer. 3 A 3vent 3stack 3prevents 3the
3development 3of 3excessive 3pressures 3in 3the 3lower 3regions 3of 3the 3drainage
3stack 3by 3relieving 3the 3air 3that 3is 3rapidly 3carried 3down 3the 3drainage 3stack. 3It
3does 3not 3include 3vertical 3fixture 3drains 3and 3branch 3vents 3that 3do 3not 3pass
3through 3more 3than 3two 3stories 3before 3being 3connected 3to 3the 3soil 3or 3waste
3stack 3or 3vent 3stack.
What 3is 3a 3general 3term 3for 3any 3vertical 3line 3of 3soil 3or 3waste 3piping 3that 3collects
3water 3and 3wastes 3from 3fixture 3drains 3and 3horizontal 3branch 3drains 3from 3two
3or 3more 3floors 3of 3a 3building? 3- 3 correct 3answer. 3 A 3Stack.
Properties 3of 3uniform 3flow 3apply 3to 3branches 3of 3what 3length 3and 3longer? 3-
3 correct 3answer. 3 5 3feet
Special 3wastes, 3tank 3overflows, 3tank 3emptying 3lines, 3releif 3valve 3discharges,
3etc. 3should 3discharge 3where 3and 3why? 3- 3 correct 3answer. 3 Through 3an 3air 3break
3to 3an 3appropriate 3receptacle 3(floor 3drain 3or 3other) 3to 3prevent
3overpressurization 3of 3the 3drainage 3system.
High 3temperature 3wastes 3should 3be 3cooled 3to 3what 3temperature 3before
3discharging 3into 3the 3drainage 3system? 3- 3 correct 3answer. 3 140F
When 3interior 3drainage 3piping 3developed 3length 3reaches 3100 3feet, 3what
3should 3happen 3and 3why? 3- 3 correct 3answer. 3 A 3vent 3to 3atmosphere 3should
3be 3provided. 3It 3should 3run 3independently 3through 3the 3roof, 3this 3is 3to
3prevent 3the 3rapid 3fouling 3of 3the 3pipe 3due 3to 3the 3growth 3of 3slime 3and 3fungi
3in 3the 3absence 3of 3air 3circulation.
The 3sizing 3for 3indirect 3wastes 3is 3the 3same 3as 3direct-waste 3connections
3with 3what 3exception? 3- 3 correct 3answer. 3 Due 3to 3the 3low 3velocities 3usually
3present 3in 3indirect 3wastes, 3stoppages 3are 3more 3prevalent, 3and 3cleanouts
3should 3be 3provided 3at 3every 3possible 3location.
For 3an 3indirect 3waste, 3the 3discharge 3outlet 3should 3be 3what? 3- 3 correct
3answer. 3 A 3minimum 3of 31.5 3times 3the 3indirect 3pipe 3size 3above 3the 3flood
3level 3of 3the 3receptacle.
How 3can 3the 3fixture 3unit 3flow 3rate 3be 3calculated? 3- 3 correct 3answer. 3 By 3dividing
3the 3total 3discharge 3flow 3in 3gallons 3per 3minute 3of 3a 3single 3fixture 3divided 3by
37.5 3gal/ft^3
What 3factors 3do 3FUs 3account 3for? 3- 3 correct 3answer. 3 Application 3in
complete solutions.
Front - correct answer. Back
What is the specific weight of water? - correct answer. 62.4 lbs per cubic foot
What happens in a storm and sanitary system after it passes the water
test? - correct answer. A smoke pressure test is recommended with a
smoke pressure of 1 in wc to prove the system gas tight.
Is an air test acceptable for a storm and sanitary system? - correct answer.
Yes, if a water test is not possible, at a pressure of 5 psi, are tests are
impractical and costly
What are the testing procedures for the storm and sanitary system? -
correct answer. A water test upon completion of the rough piping and prior
to concealment of 10 ft wc minimum (except the topmost 10 feet of pipe),
not to exceed 100 ft wc. If system is higher than 100 feet, test plugs must
be installed to facilitate testing, rarely are more than 7 stories tested at
one time. A peppermint oil test may also be done with 2 oz of peppermint
oil and 10 qt boiling water, and searching for peppermint smell at leaks,
however it is difficult to pinpoint the leak by this method
The maximum length from the vent connection to any future drain outlet is
required by code, why, how long is the distance (listed in the book), and
what’s the exception? - correct answer. To prevent a dead end where
slime, sludge and fungi can grow, 2 feet, unless the piping must be extended
to an accessible location for a cleanout
A sanitary tee may be used in the vertical but what may not be used in the
vertical and why? - correct answer. A double sanitary tee because the
possibility of flow crossover
,and excessive pressures when one branch is discharging and the other
isn’t are possible
What are the slopes of pipe inside the building that correspond to 2 fps
velocity? - correct answer. 1/4 in per foot for 3 in and smaller 1/8 in per foot
for larger pipe all elbows, taps, tees etc are tapped at a pitch of 1/4” per
foot
Where should cleanouts be provided? - correct answer. 1) Inside or outside
the building at the point of exit (use a wye branch) 2) at every change in
direction greater than 45 degrees 3) every 50 feet for piping 4” and less,
and 100 ft for larger piping 4) underground piping larger than 10 in should
be provided with manholes at every change in direction and every 150 feet
5) at the base of all stacks 6) as required by code
What size cleanouts are provided in piping? - correct answer. Piping up to 4
inches, the cleanout is the same size as the pipe. Piping greater than 4
inches, 4 inch cleanouts are adequate.
What should be installed in the house drain if there is a danger of backflow
of sewage into the building? Whats the difference? - correct answer. A
backwater valve or a combination BWV with manually operated gate valve.
The BWV does not interfere with the airflow throughout the system, and the
gate valve is recommended where there is a history of backflow as a positive
means of protection.
Branch connections to the house drain should be made where and why? -
correct answer. At the upper portion of the pipe (above the 1/2 - 2/3 full
mark) because: 1) there is a lower chance of stoppages in the branch 2)
there is less flow interference at the point of connection 3) When there is no
flow in the branch, the full area of the pipe is available to relieve pneumatic
pressure fluctuations in the house drain
How many fixture units are equivalent to 1 gpm continuous or
semicontinuous flow and what are examples of these types of flow? - correct
answer. 2 FUs, sump pumps, ejectors, air conditioning equipment, water
cooled, equipment, etc
What minimum slopes are required for building drains and why? - correct
answer. 3 in pipe and smaller: 1/4 in/ft 4-6 in pipe: 1/8 in/ft 8 in pipe and
larger: 1/16 in/ft to maintain 2 fps scouring action if low flow fixtures are
present, 1/4 in/ft for all is a good idea
House drains are designed to flow how full? - correct answer. 1/2 full to 3/4
full max under uniform flow conditions
What is a house (building) drain? - correct answer. The lowest piping of a
gravity drainage system that receives the discharge from soil, waste, and
other drainage pipes inside the building that extends a short distance from
the building and conveys the drainage to the building sewer
,What 3is 3the 3measurement 3from 3horizontal 3that 3separates 3horizontal 3and
3vertical 3drainage 3stacks? 3- 3 correct 3answer. 3 45 3degrees
Does 3an 3interior 3drainage 3stack 3that 3offsets 345 3degrees 3or 3less 3from 3the
3vertical 3require 3a 3change 3in 3size? 3- 3 correct 3answer. 3 No. 3Any 3more 3than 3a
345 3degree 3offset 3requires 3sizing 3the 3offset 3as 3a 3house 3drain.
What 3is 3a 3branch 3interval? 3- 3 correct 3answer. 3 A 3building 3story 3or 3a 3distance
3between 3two 3branch 3connections 3greater 3than 38 3feet 3apart.
Describe 3the 3procedure 3for 3sizing 3interior 3drainage 3stacks. 3- 3 correct
3answer. 3 1) 3First 3size 3the 3horizontal 3branches 3connecting 3to 3the 3stack 32)
3Determine 3the 3minimum 3size 3that 3will 3accept 3each 3branch 3at 3one 3branch
3interval 33) 3Total 3all 3fixture 3units 3connected 3to 3the 3stack, 3and 3determine
3the 3size. 3The 3minimum 3size 3must 3be 3at 3least 3equal 3to 3the 3largest 3diameter
3required 3at 3the 3base. 3You 3may 3reduce 3in 3size 3at 3upper 3branch 3intervals,
3but 3never 3by 3more 3than 31/2 3the 3largest 3size.
What 3is 3the 3total 3recommended 3maximum 3permissible 3flow 3in 3a 3stack? 3-
3 correct 3answer. 37/24 3of 3the 3total 3cross 3sectional 3area 3of 3the 3stack.
Where 3should 3and 3shouldn’t 3you 3connect 3branch 3connections 3to 3stack
3offsets? 3- 3correct 3answer. 3 Not 3to 3the 3horizontal 3offset 3to 3the 3stack 3if 3at 3all
3possible, 3unless 3its 3at 3least 310 3pipe 3diameters 3downstream, 3and 3ideally 32
3feet 3above 3the 3offset 3or 32 3feet 3below 3to 3avoid 3pressure 3fluctuations.
What 3can 3minimize 3hydraulic 3jump? 3- 3 correct 3answer. 3 Increasing 3the 3slope
3of 3the 3horizontal 3drain. 3Connecting 3to 3a 3horizontal 3drain 3that 3is 3larger 3than
3the 3stack.
Any 3offset 3of 3the 3stack 3greater 3than 3what 3can 3cause 3hydraulic 3jump? 3-
3 correct 3answer. 345 3degrees
When 3does 3terminal 3velocity 3occur 3in 3a 3drainage 3stack? 3- 3 correct 3answer. 3 It
3is 3achieved 3at 3approximately 310 3- 315 3fps 3and 3this 3velocity 3is 3achieved
3within 310 3- 315 3feet 3of 3fall 3from 3the 3point 3of 3entry.
A 3drainage 3stack 3should 3never 3be 3designed 3for 3a 3capacity 3greater 3than
3what 3and 3why? 3- 3correct 3answer. 3 One-thrid 3full, 3because 3the 3pressure
3fluctuations 3in 3the 3system 3could 3greatly 3exceed 3the 3maximum 31 3in 3water
3column 3criterion 3and 3lose 3their 3seal 3by 3siphonage 3blowout
What 3is 3one 3positive 3and 3one 3negative 3of 3a 3tee-wye 3fitting? 3- 3 correct
3answer. 3 The 3long 3radius 3tee-wye 3fitting 3gives 3the 3water 3a 3greater
3downward 3component 3than 3a 3sanitary 3tee, 3but 3also 3has 3a 3greater
3probability 3of 3siphoning 3the 3traps
How 3are 3horizontal 3branch 3connections 3to 3the 3stack 3made? 3- 3 correct
3answer. 3 With 3a 3sanitary 3tee 3(a 3short 3radius 3tee-wye, 3vertical 3position 3only)
3or 3with 3a 3long 3radius 3tee-wye
, (vertical 3or 3horizontal 3position). 3(The 3tee-wye 3is 3also 3called 3a 3combination 3wye
3and 3one- 3eighth 3bend)
What 3is 3the 3difference 3between 3soil 3stacks 3and 3waste 3stacks? 3- 3 correct
3answer. 3 Soil 3stacks 3collect 3wastes 3that 3contain 3fecal 3matter, 3and 3waste
3stacks 3collect 3wastes 3that 3do 3not 3contain 3fecal 3matter 3(lavatories, 3sinks,
3etc)
What 3is 3a 3vent 3stack? 3- 3 correct 3answer. 3 A 3vent 3stack 3prevents 3the
3development 3of 3excessive 3pressures 3in 3the 3lower 3regions 3of 3the 3drainage
3stack 3by 3relieving 3the 3air 3that 3is 3rapidly 3carried 3down 3the 3drainage 3stack. 3It
3does 3not 3include 3vertical 3fixture 3drains 3and 3branch 3vents 3that 3do 3not 3pass
3through 3more 3than 3two 3stories 3before 3being 3connected 3to 3the 3soil 3or 3waste
3stack 3or 3vent 3stack.
What 3is 3a 3general 3term 3for 3any 3vertical 3line 3of 3soil 3or 3waste 3piping 3that 3collects
3water 3and 3wastes 3from 3fixture 3drains 3and 3horizontal 3branch 3drains 3from 3two
3or 3more 3floors 3of 3a 3building? 3- 3 correct 3answer. 3 A 3Stack.
Properties 3of 3uniform 3flow 3apply 3to 3branches 3of 3what 3length 3and 3longer? 3-
3 correct 3answer. 3 5 3feet
Special 3wastes, 3tank 3overflows, 3tank 3emptying 3lines, 3releif 3valve 3discharges,
3etc. 3should 3discharge 3where 3and 3why? 3- 3 correct 3answer. 3 Through 3an 3air 3break
3to 3an 3appropriate 3receptacle 3(floor 3drain 3or 3other) 3to 3prevent
3overpressurization 3of 3the 3drainage 3system.
High 3temperature 3wastes 3should 3be 3cooled 3to 3what 3temperature 3before
3discharging 3into 3the 3drainage 3system? 3- 3 correct 3answer. 3 140F
When 3interior 3drainage 3piping 3developed 3length 3reaches 3100 3feet, 3what
3should 3happen 3and 3why? 3- 3 correct 3answer. 3 A 3vent 3to 3atmosphere 3should
3be 3provided. 3It 3should 3run 3independently 3through 3the 3roof, 3this 3is 3to
3prevent 3the 3rapid 3fouling 3of 3the 3pipe 3due 3to 3the 3growth 3of 3slime 3and 3fungi
3in 3the 3absence 3of 3air 3circulation.
The 3sizing 3for 3indirect 3wastes 3is 3the 3same 3as 3direct-waste 3connections
3with 3what 3exception? 3- 3 correct 3answer. 3 Due 3to 3the 3low 3velocities 3usually
3present 3in 3indirect 3wastes, 3stoppages 3are 3more 3prevalent, 3and 3cleanouts
3should 3be 3provided 3at 3every 3possible 3location.
For 3an 3indirect 3waste, 3the 3discharge 3outlet 3should 3be 3what? 3- 3 correct
3answer. 3 A 3minimum 3of 31.5 3times 3the 3indirect 3pipe 3size 3above 3the 3flood
3level 3of 3the 3receptacle.
How 3can 3the 3fixture 3unit 3flow 3rate 3be 3calculated? 3- 3 correct 3answer. 3 By 3dividing
3the 3total 3discharge 3flow 3in 3gallons 3per 3minute 3of 3a 3single 3fixture 3divided 3by
37.5 3gal/ft^3
What 3factors 3do 3FUs 3account 3for? 3- 3 correct 3answer. 3 Application 3in
