Class A Water Operator Exam Ques ons and answers
New!! 2025/2026 updated
How many Training Hours and experience for a class D Water Operator - CORRECT ANSWERS
16 Hours Training and No Experience
How many Training Hours and experience for a class C Water Operator - CORRECT ANSWERS
36 Hours Training and 1 year Experience
How many Training Hours and experience for a class B Water Operator - CORRECT ANSWERS
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 - CORRECT ANSWERS
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 - CORRECT ANSWERS 32
Hours and no experience
How many Training Hours and experience for a Class B Lab Operator - CORRECT ANSWERS 32
hours of C and 32 hours of B and 6 months experience. ***associate in science can subs/tute
32hrs of C level training
How many Training Hours and experience for a Class A Lab Operator - CORRECT ANSWERS 32
hours of B and 1 year experience. ***Must include a Bachelor in science
How many Training Hours and experience for a Class C Distribu/on Operator - CORRECT
ANSWERS 36hours and 1 year experience
,How many Training Hours and experience for a Distribu/on Technician - CORRECT ANSWERS 8
hours and no training.
Community Water System - CORRECT ANSWERS A public water supply that has at least 15
service connec/ons or serves 25 or more persons on a regular basis
Primary Contaminants - CORRECT ANSWERS Contaminants iden/fies by the EPA as harmful to
umal health
Maximum Containment Level (MCL) - CORRECT ANSWERS The level in which contaminants
must not exceed or public no/fica/on is required.
Cryptosporidium - CORRECT ANSWERS A microsocpic parasite that can be found in water. It
produces cysts that are very resistant to harsh environmental condi/ons. It is responsible for
intes/nal illness called cryptosporidiosis. Symptoms include diarrhea, cramps, gas, bodily
discomfort, fa/gue, and weight loss. Occurs one week a9er exposure and can last for 1-4 weeks
Disinfec/on Profiling - CORRECT ANSWERS A water system assesses the level of disinfec/on
currently provided and then determines the impact a proposed change in disinfec/on prac/ce
would have.
E. coli - CORRECT ANSWERS 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 o9en seen in the stool. Symptoms begin 1-9 days a9er exposure
and last a week or less.
Giardia - CORRECT ANSWERS A microscopic parasite that can be found in water. It produces
cysts that are resistant to harsh environmental condi/ons. Giardia causes intes/nal illness called
giardiasis. Symptoms simular to cryptosporidiosis. Vomi/on, chills, headache and fever may also
occur. Symptoms begin one week a9er exposure and can last up to a month.
, Hard Water - CORRECT ANSWERS A characteris/c of water caused mainly by the salts of
calcium (Ca++) and magnesium (Mg++). Undesirable due to forma/on 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) - CORRECT ANSWERS The highest level of
disinfectant allowed in drinking water. Standards set by the US EPA
Microbial Pathogens - CORRECT ANSWERS Micro-organisms that cause disease
Safe Drinking Water Act (SDWA) - CORRECT ANSWERS An Act passed by the US Congress in
1974. It establishes a coopera/ve program among local, state, and federal agencies to ensure
safe drinking water for customers.
Ch 1 - One gallon of water weighs - CORRECT ANSWERS 8.34 pounds
Ch 1- The average domes/c water usage per person per day is usually somewhere in the range
of - CORRECT ANSWERS 100-130 gallons
Ch 1 -Probably the most important source of informa/on to use when implemen/ng changes in
process control at a water plant is - CORRECT ANSWERS Lab Results
Ch 1 - The most important duty of a water plant operator is to - CORRECT ANSWERS Help to
protect the health and well-being of the community
Apparent color - CORRECT ANSWERS The color visible in water
New!! 2025/2026 updated
How many Training Hours and experience for a class D Water Operator - CORRECT ANSWERS
16 Hours Training and No Experience
How many Training Hours and experience for a class C Water Operator - CORRECT ANSWERS
36 Hours Training and 1 year Experience
How many Training Hours and experience for a class B Water Operator - CORRECT ANSWERS
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 - CORRECT ANSWERS
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 - CORRECT ANSWERS 32
Hours and no experience
How many Training Hours and experience for a Class B Lab Operator - CORRECT ANSWERS 32
hours of C and 32 hours of B and 6 months experience. ***associate in science can subs/tute
32hrs of C level training
How many Training Hours and experience for a Class A Lab Operator - CORRECT ANSWERS 32
hours of B and 1 year experience. ***Must include a Bachelor in science
How many Training Hours and experience for a Class C Distribu/on Operator - CORRECT
ANSWERS 36hours and 1 year experience
,How many Training Hours and experience for a Distribu/on Technician - CORRECT ANSWERS 8
hours and no training.
Community Water System - CORRECT ANSWERS A public water supply that has at least 15
service connec/ons or serves 25 or more persons on a regular basis
Primary Contaminants - CORRECT ANSWERS Contaminants iden/fies by the EPA as harmful to
umal health
Maximum Containment Level (MCL) - CORRECT ANSWERS The level in which contaminants
must not exceed or public no/fica/on is required.
Cryptosporidium - CORRECT ANSWERS A microsocpic parasite that can be found in water. It
produces cysts that are very resistant to harsh environmental condi/ons. It is responsible for
intes/nal illness called cryptosporidiosis. Symptoms include diarrhea, cramps, gas, bodily
discomfort, fa/gue, and weight loss. Occurs one week a9er exposure and can last for 1-4 weeks
Disinfec/on Profiling - CORRECT ANSWERS A water system assesses the level of disinfec/on
currently provided and then determines the impact a proposed change in disinfec/on prac/ce
would have.
E. coli - CORRECT ANSWERS 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 o9en seen in the stool. Symptoms begin 1-9 days a9er exposure
and last a week or less.
Giardia - CORRECT ANSWERS A microscopic parasite that can be found in water. It produces
cysts that are resistant to harsh environmental condi/ons. Giardia causes intes/nal illness called
giardiasis. Symptoms simular to cryptosporidiosis. Vomi/on, chills, headache and fever may also
occur. Symptoms begin one week a9er exposure and can last up to a month.
, Hard Water - CORRECT ANSWERS A characteris/c of water caused mainly by the salts of
calcium (Ca++) and magnesium (Mg++). Undesirable due to forma/on 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) - CORRECT ANSWERS The highest level of
disinfectant allowed in drinking water. Standards set by the US EPA
Microbial Pathogens - CORRECT ANSWERS Micro-organisms that cause disease
Safe Drinking Water Act (SDWA) - CORRECT ANSWERS An Act passed by the US Congress in
1974. It establishes a coopera/ve program among local, state, and federal agencies to ensure
safe drinking water for customers.
Ch 1 - One gallon of water weighs - CORRECT ANSWERS 8.34 pounds
Ch 1- The average domes/c water usage per person per day is usually somewhere in the range
of - CORRECT ANSWERS 100-130 gallons
Ch 1 -Probably the most important source of informa/on to use when implemen/ng changes in
process control at a water plant is - CORRECT ANSWERS Lab Results
Ch 1 - The most important duty of a water plant operator is to - CORRECT ANSWERS Help to
protect the health and well-being of the community
Apparent color - CORRECT ANSWERS The color visible in water
