ABYC Systems Certification Exam Review questions
and answers with solutions
What is the most often used materials for potable water systems? - ANSWER Polyethylene
Name 5 materials allowable for contact use in potable water systems: - ANSWER 1. Copper
Alloys (incl. bronze, brass and nickel-copper)
2. AISI Type 300 series stainless steel
3. Glass-lined metal
4. FDA approved plastic
5. FDA approved rubber
What device can be used to separate potable water from other water systems? - ANSWER
Siphon Break
What is the device used to maintain a stable pressure and minimize pump cycling, and where
should it be located? - ANSWER Accumulator Tank, after pump/filter and before check-valve
At what what percentage of nominal working pressure shall the relief valve be set? - ANSWER
175%
Is a standard household type relief valve acceptable for hot water tanks? - ANSWER No, typically
these are too high (up to 400% of nominal pressure)
For the pressure reducing valve and check valve installed after a shore water connection, what
is the maximum allowable pressure? - ANSWER nominal working pressure, not to exceed 80 PSI
Where shall the storage tank be vented? - ANSWER overboard
,What is the maximum allowable pressure to which the storage tank and vent system be
subjected? - ANSWER 3 PSI or mnfg's maximum, which ever is greater.
What temperate range is required for pumps to be able to tolerate exposure? - ANSWER -40 °F
to +140 °F
When operating at an ambient temperature of 140 F, what is the max allowable surface
temperature of a pump? - ANSWER 257 F
Potable water systems must be equipped with a drain. T or F? - ANSWER True
Storage tank inlet may also serve as the tank vent. T or F? - ANSWER False
Storage tank inlet caps must be retained to prevent loss. T or F? - ANSWER True
Storage tanks must be equipped with a vent. T or F? - ANSWER True
Storage tank vent may be used for filling purposes. T or F? - ANSWER True
What rate of static pressure must a storage tank withstand? - ANSWER At least 1.5X the
pressure exerted by the distance from the tank bottom to the deck fill plate or vent, but not less
than 3 PSI.
What is the max pressure that a desalinator can impart to a storage tank? - ANSWER 3 PSI
Each desalinator must be equipped with an automatic shutoff salinity detector. T or F? -
ANSWER True
,What marking must be on pipe or tubes that are not capable of handling hot water? - ANSWER
"For Cold Water Use Only"
What is the test pressure for water heater tank 15 gal or less? over 15 gal but under 120 gal? -
ANSWER 125 PSI, 300 PSI
What is the max pressure relief valve setting for hot water tanks? - ANSWER 175 PSI
What is the max temperature relief setting for hot water tanks? - ANSWER 210 F
What is the max allowable water output temperature for hot water system? - ANSWER 125 F
All potable water system connections shall be positioned above the normal bilge water
accumulation level. T or F? - ANSWER True
Exposed metallic parts of a potable water system shall have provisions for electrical bonding. T
or F? - ANSWER True
For what reason might a holding tank collapse during pump-out? - ANSWER Improper venting
What type of MSD (Marine Sanitation Device) discharges effluent with fecal coliform bacteria
count <= 1,000 (per 100 ml) and no suspended solids? - ANSWER Type I
What type of MSD (Marine Sanitation Device) discharges effluent with fecal coliform bacteria
count <= 200 (per 100 ml) and <= 150 mg suspended solids per liter? - ANSWER Type II
, What type of MSD (Marine Sanitation Device) is designed to hold sewage or any waste derived
from sewage? - ANSWER Type III
What is the name given to the complete system including toilets, hoses, pipes, holding tanks
and fittings designed to receive, retain, vent and pump out sewage? - ANSWER Retention
System
What is the name of the system that includes all sanitation equipment and fittings designed to
receive, treat, vent and discharge sewage? - ANSWER Treatment System
What is another name for a vented loop that prevents back siphoning by breaking suction yet
allowing normal flow when pressurized? - ANSWER Siphon break
When calculating holding tank size, how many flushes per day are included in the calculation? -
ANSWER 5
What volume of human waste is used per flush when calculating holding tank size? - ANSWER
0.14 gallons
True or False: If a portable toilet is secured and fitted with a deck pump-out fitting and vent it
qualifies as a type III device. - ANSWER True
Why must careful consideration be given to the location and routing of inlet and discharge lines
for manual flush toilets when the "shut-off" merely bleeds air into the inlet line? - ANSWER
Prevention of siphoning
When and why must siphon breaks be installed in a sewage system? - ANSWER Whenever
components are installed below the max heeled water line - to prevent back flow into the vessel
or unintentional siphoning of untreated effluent overboard.
and answers with solutions
What is the most often used materials for potable water systems? - ANSWER Polyethylene
Name 5 materials allowable for contact use in potable water systems: - ANSWER 1. Copper
Alloys (incl. bronze, brass and nickel-copper)
2. AISI Type 300 series stainless steel
3. Glass-lined metal
4. FDA approved plastic
5. FDA approved rubber
What device can be used to separate potable water from other water systems? - ANSWER
Siphon Break
What is the device used to maintain a stable pressure and minimize pump cycling, and where
should it be located? - ANSWER Accumulator Tank, after pump/filter and before check-valve
At what what percentage of nominal working pressure shall the relief valve be set? - ANSWER
175%
Is a standard household type relief valve acceptable for hot water tanks? - ANSWER No, typically
these are too high (up to 400% of nominal pressure)
For the pressure reducing valve and check valve installed after a shore water connection, what
is the maximum allowable pressure? - ANSWER nominal working pressure, not to exceed 80 PSI
Where shall the storage tank be vented? - ANSWER overboard
,What is the maximum allowable pressure to which the storage tank and vent system be
subjected? - ANSWER 3 PSI or mnfg's maximum, which ever is greater.
What temperate range is required for pumps to be able to tolerate exposure? - ANSWER -40 °F
to +140 °F
When operating at an ambient temperature of 140 F, what is the max allowable surface
temperature of a pump? - ANSWER 257 F
Potable water systems must be equipped with a drain. T or F? - ANSWER True
Storage tank inlet may also serve as the tank vent. T or F? - ANSWER False
Storage tank inlet caps must be retained to prevent loss. T or F? - ANSWER True
Storage tanks must be equipped with a vent. T or F? - ANSWER True
Storage tank vent may be used for filling purposes. T or F? - ANSWER True
What rate of static pressure must a storage tank withstand? - ANSWER At least 1.5X the
pressure exerted by the distance from the tank bottom to the deck fill plate or vent, but not less
than 3 PSI.
What is the max pressure that a desalinator can impart to a storage tank? - ANSWER 3 PSI
Each desalinator must be equipped with an automatic shutoff salinity detector. T or F? -
ANSWER True
,What marking must be on pipe or tubes that are not capable of handling hot water? - ANSWER
"For Cold Water Use Only"
What is the test pressure for water heater tank 15 gal or less? over 15 gal but under 120 gal? -
ANSWER 125 PSI, 300 PSI
What is the max pressure relief valve setting for hot water tanks? - ANSWER 175 PSI
What is the max temperature relief setting for hot water tanks? - ANSWER 210 F
What is the max allowable water output temperature for hot water system? - ANSWER 125 F
All potable water system connections shall be positioned above the normal bilge water
accumulation level. T or F? - ANSWER True
Exposed metallic parts of a potable water system shall have provisions for electrical bonding. T
or F? - ANSWER True
For what reason might a holding tank collapse during pump-out? - ANSWER Improper venting
What type of MSD (Marine Sanitation Device) discharges effluent with fecal coliform bacteria
count <= 1,000 (per 100 ml) and no suspended solids? - ANSWER Type I
What type of MSD (Marine Sanitation Device) discharges effluent with fecal coliform bacteria
count <= 200 (per 100 ml) and <= 150 mg suspended solids per liter? - ANSWER Type II
, What type of MSD (Marine Sanitation Device) is designed to hold sewage or any waste derived
from sewage? - ANSWER Type III
What is the name given to the complete system including toilets, hoses, pipes, holding tanks
and fittings designed to receive, retain, vent and pump out sewage? - ANSWER Retention
System
What is the name of the system that includes all sanitation equipment and fittings designed to
receive, treat, vent and discharge sewage? - ANSWER Treatment System
What is another name for a vented loop that prevents back siphoning by breaking suction yet
allowing normal flow when pressurized? - ANSWER Siphon break
When calculating holding tank size, how many flushes per day are included in the calculation? -
ANSWER 5
What volume of human waste is used per flush when calculating holding tank size? - ANSWER
0.14 gallons
True or False: If a portable toilet is secured and fitted with a deck pump-out fitting and vent it
qualifies as a type III device. - ANSWER True
Why must careful consideration be given to the location and routing of inlet and discharge lines
for manual flush toilets when the "shut-off" merely bleeds air into the inlet line? - ANSWER
Prevention of siphoning
When and why must siphon breaks be installed in a sewage system? - ANSWER Whenever
components are installed below the max heeled water line - to prevent back flow into the vessel
or unintentional siphoning of untreated effluent overboard.
