ILLINOIS CLASS C WATER
CERTIFICATION EXAM QUESTIONS
AND ANSWERS. VERIFIED 2026.
When using a sodium Fluoride Saturator Why should you use Soft water? - ANS To prevent
the precipitation of calcium and magnesium fluoride
What is a laglier Index? - ANS The Langelier Index is an approximate indicator of the degree
of saturation of calcium carbonate in water. It is calculated (58 KB) using the pH, alkalinity,
calcium concentration, total dissolved solids, and water temperature of a water sample
collected at the tap.
What does a Latern ring do, and where is it located? - ANS A perforated hollow ring keeps the
shaft cool and lubricated in the center of a packing box
What does a well's wear ring do? - ANS Close running renewable clearance which reduces
leaking. it is in the pump case on the impeller
How do you install packing? - ANS Cut with a beveled edge, place in gland, tighten gland
snugly, alowing a small amount of waret to leak.
How do you mix water and acid? - ANS Always add acid to water (strong to weak)
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, How do you figure how long it will take water level to rise 2 foot? - ANS 1. volume of tank
2.Gallons per foot 3.What is the flow?
What type of Fluoride do you not mix with Chlorine? - ANS HFS Acid
How often do backflow devices (RPZ) need to be tested? - ANS once a year
How long do you wait to read the results after a free chlorine reagent is mixed with water? -
ANS within one minute
How long do you wait to read the results after a total chlorine reagent is mixed with water? -
ANS after three but before six
Classify PH levels - ANS 7 is neutral above 7 is alkaline below 7 is acidic
when should and altitude valve on a storage tank open? - ANS when water is being called for
due to lower levels in higher elevation tanks
What reacts with Chlorine to create "combined Chlorine?" - ANS Nitrogen tricloride(NCl3),
dichloramine (NHCl2), and monochloromine(NH2Cl)
One-ton Chlorine gas cylinder what valve does chlorine gas come from? - ANS The top valve
What does a chlorine cylinder need to convert liquid chlorine into gas? - ANS An Evaporator
What is the per-capita use of water in the US? - ANS 98-100 gallons
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
CERTIFICATION EXAM QUESTIONS
AND ANSWERS. VERIFIED 2026.
When using a sodium Fluoride Saturator Why should you use Soft water? - ANS To prevent
the precipitation of calcium and magnesium fluoride
What is a laglier Index? - ANS The Langelier Index is an approximate indicator of the degree
of saturation of calcium carbonate in water. It is calculated (58 KB) using the pH, alkalinity,
calcium concentration, total dissolved solids, and water temperature of a water sample
collected at the tap.
What does a Latern ring do, and where is it located? - ANS A perforated hollow ring keeps the
shaft cool and lubricated in the center of a packing box
What does a well's wear ring do? - ANS Close running renewable clearance which reduces
leaking. it is in the pump case on the impeller
How do you install packing? - ANS Cut with a beveled edge, place in gland, tighten gland
snugly, alowing a small amount of waret to leak.
How do you mix water and acid? - ANS Always add acid to water (strong to weak)
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, How do you figure how long it will take water level to rise 2 foot? - ANS 1. volume of tank
2.Gallons per foot 3.What is the flow?
What type of Fluoride do you not mix with Chlorine? - ANS HFS Acid
How often do backflow devices (RPZ) need to be tested? - ANS once a year
How long do you wait to read the results after a free chlorine reagent is mixed with water? -
ANS within one minute
How long do you wait to read the results after a total chlorine reagent is mixed with water? -
ANS after three but before six
Classify PH levels - ANS 7 is neutral above 7 is alkaline below 7 is acidic
when should and altitude valve on a storage tank open? - ANS when water is being called for
due to lower levels in higher elevation tanks
What reacts with Chlorine to create "combined Chlorine?" - ANS Nitrogen tricloride(NCl3),
dichloramine (NHCl2), and monochloromine(NH2Cl)
One-ton Chlorine gas cylinder what valve does chlorine gas come from? - ANS The top valve
What does a chlorine cylinder need to convert liquid chlorine into gas? - ANS An Evaporator
What is the per-capita use of water in the US? - ANS 98-100 gallons
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
