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Class A Water Operator Questions and
Answers
How many Training Hours and experience for a class D Water
Operator Ans: 16 Hours Training and No Experience
How many Training Hours and experience for a class C Water
Operator Ans: 36 Hours Training and 1 year Experience
How many Training Hours and experience for a class B Water
Operator Ans: 100 Hours Training and 3 years Experience (must
include 1 year of hands on experience)
How many Training Hours and experience for a class A Water
Operator Ans: 200 Hours Training and 5 years Experience (must
include 2 years of hands on experience)
How many Training Hours and experience for a Class C Lab
Operator Ans: 32 Hours and no experience
How many Training Hours and experience for a Class B Lab
Operator Ans: 32 hours of C and 32 hours of B and 6 months
experience. ***associate in science can substitute 32hrs of C level
training
How many Training Hours and experience for a Class A Lab
Operator Ans: 32 hours of B and 1 year experience. ***Must
include a Bachelor in science
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How many Training Hours and experience for a Class C
Distribution Operator Ans: 36hours and 1 year experience
How many Training Hours and experience for a Distribution
Technician Ans: 8 hours and no training.
Community Water System Ans: A public water supply that has at
least 15 service connections or serves 25 or more persons on a
regular basis
Primary Contaminants Ans: Contaminants identifies by the EPA
as harmful to umal health
Maximum Containment Level (MCL) Ans: The level in which
contaminants must not exceed or public notification is required.
Cryptosporidium Ans: A microsocpic parasite that can be found
in water. It produces cysts that are very resistant to harsh
environmental conditions. It is responsible for intestinal illness
called cryptosporidiosis. Symptoms include diarrhea, cramps, gas,
bodily discomfort, fatigue, and weight loss. Occurs one week after
exposure and can last for 1-4 weeks
Disinfection Profiling Ans: A water system assesses the level of
disinfection currently provided and then determines the impact a
proposed change in disinfection practice would have.
E. coli Ans: A bacterium that is commonly used as an indicator of
human health risk from harmful micro organisms that can be
present in water. Symptoms include sever cramps and diarrhea.
Blood is often seen in the stool. Symptoms begin 1-9 days after
exposure and last a week or less.
Giardia Ans: A microscopic parasite that can be found in water. It
produces cysts that are resistant to harsh environmental
conditions. Giardia causes intestinal illness called giardiasis.
Symptoms simular to cryptosporidiosis. Vomition, chills, headache
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and fever may also occur. Symptoms begin one week after
exposure and can last up to a month.
Hard Water Ans: A characteristic of water caused mainly by the
salts of calcium (Ca++) and magnesium (Mg++). Undesirable due to
formation of soap curds, increase use of soap, and scale deposits
in boilers and water heaters. Defines as having hardness of
100mg/L or greater
Maximum Residual Disinfectant Level (MDRLs) Ans: The highest
level of disinfectant allowed in drinking water. Standards set by
the US EPA
Microbial Pathogens Ans: Micro-organisms that cause disease
Safe Drinking Water Act (SDWA) Ans: An Act passed by the US
Congress in 1974. It establishes a cooperative program among
local, state, and federal agencies to ensure safe drinking water for
customers.
Ch 1 - One gallon of water weighs Ans: 8.34 pounds
Ch 1- The average domestic water usage per person per day is
usually somewhere in the range of Ans: 100-130 gallons
Ch 1 -Probably the most important source of information to use
when implementing changes in process control at a water plant is
Ans: Lab Results
Ch 1 - The most important duty of a water plant operator is to
Ans: Help to protect the health and well-being of the community
Apparent color Ans: The color visible in water
True color Ans: Dissolved material contribution to color and is
not removed through simple filtration (i.e. coffee or tea). Measure
in Color Units (CUs) using a clear glass tube called a Nessler tub.
© 2025 All rights reserved
Class A Water Operator Questions and
Answers
How many Training Hours and experience for a class D Water
Operator Ans: 16 Hours Training and No Experience
How many Training Hours and experience for a class C Water
Operator Ans: 36 Hours Training and 1 year Experience
How many Training Hours and experience for a class B Water
Operator Ans: 100 Hours Training and 3 years Experience (must
include 1 year of hands on experience)
How many Training Hours and experience for a class A Water
Operator Ans: 200 Hours Training and 5 years Experience (must
include 2 years of hands on experience)
How many Training Hours and experience for a Class C Lab
Operator Ans: 32 Hours and no experience
How many Training Hours and experience for a Class B Lab
Operator Ans: 32 hours of C and 32 hours of B and 6 months
experience. ***associate in science can substitute 32hrs of C level
training
How many Training Hours and experience for a Class A Lab
Operator Ans: 32 hours of B and 1 year experience. ***Must
include a Bachelor in science
© 2025 All rights reserved
, 2 | Page
How many Training Hours and experience for a Class C
Distribution Operator Ans: 36hours and 1 year experience
How many Training Hours and experience for a Distribution
Technician Ans: 8 hours and no training.
Community Water System Ans: A public water supply that has at
least 15 service connections or serves 25 or more persons on a
regular basis
Primary Contaminants Ans: Contaminants identifies by the EPA
as harmful to umal health
Maximum Containment Level (MCL) Ans: The level in which
contaminants must not exceed or public notification is required.
Cryptosporidium Ans: A microsocpic parasite that can be found
in water. It produces cysts that are very resistant to harsh
environmental conditions. It is responsible for intestinal illness
called cryptosporidiosis. Symptoms include diarrhea, cramps, gas,
bodily discomfort, fatigue, and weight loss. Occurs one week after
exposure and can last for 1-4 weeks
Disinfection Profiling Ans: A water system assesses the level of
disinfection currently provided and then determines the impact a
proposed change in disinfection practice would have.
E. coli Ans: A bacterium that is commonly used as an indicator of
human health risk from harmful micro organisms that can be
present in water. Symptoms include sever cramps and diarrhea.
Blood is often seen in the stool. Symptoms begin 1-9 days after
exposure and last a week or less.
Giardia Ans: A microscopic parasite that can be found in water. It
produces cysts that are resistant to harsh environmental
conditions. Giardia causes intestinal illness called giardiasis.
Symptoms simular to cryptosporidiosis. Vomition, chills, headache
© 2025 All rights reserved
, 3 | Page
and fever may also occur. Symptoms begin one week after
exposure and can last up to a month.
Hard Water Ans: A characteristic of water caused mainly by the
salts of calcium (Ca++) and magnesium (Mg++). Undesirable due to
formation of soap curds, increase use of soap, and scale deposits
in boilers and water heaters. Defines as having hardness of
100mg/L or greater
Maximum Residual Disinfectant Level (MDRLs) Ans: The highest
level of disinfectant allowed in drinking water. Standards set by
the US EPA
Microbial Pathogens Ans: Micro-organisms that cause disease
Safe Drinking Water Act (SDWA) Ans: An Act passed by the US
Congress in 1974. It establishes a cooperative program among
local, state, and federal agencies to ensure safe drinking water for
customers.
Ch 1 - One gallon of water weighs Ans: 8.34 pounds
Ch 1- The average domestic water usage per person per day is
usually somewhere in the range of Ans: 100-130 gallons
Ch 1 -Probably the most important source of information to use
when implementing changes in process control at a water plant is
Ans: Lab Results
Ch 1 - The most important duty of a water plant operator is to
Ans: Help to protect the health and well-being of the community
Apparent color Ans: The color visible in water
True color Ans: Dissolved material contribution to color and is
not removed through simple filtration (i.e. coffee or tea). Measure
in Color Units (CUs) using a clear glass tube called a Nessler tub.
© 2025 All rights reserved
