WATER OPERATOR CLASS D
CERTIFICATION EXAMINATION 2026
PREMIUM QUESTIONS AND SOLUTIONS
◉ Liquid bleach used in PWS must be ______ approved.
Answer: NSF
◉ T/F: Primary components of a gas feed chlorinator include an
injector, flowrate controller, rotameter, and mixing tank.
Answer: False (injector, vacuum regulator, flowrate controller,
rotameter- *not a mixing tank*)
◉ The maximum sustained gas withdrawal rate for pressure
transmission 150 lb cylinders is ____ lbs/day
Answer: 40
◉ T/F: Utility operators use chlorine in three commercial forms:
1) pure chlorine in the liquid or gas state
2) bleach solutions
3) granular/tablet compounds
Answer: True
,◉ T/F: If chlorine contacts the skin, flush with an emergency shower
or garden hose for at least an hour.
Answer: False (15 minutes)
◉ Hypochlorous acid is the disinfectant and the _____ residual.
Answer: Free
◉ If a major chlorine leak occurs, call the supplier and ______.
Answer: TCEQ
◉ The rotameter indicates the feed rate in _____ per day
Answer: pounds
◉ T/F: Chlorine reacts with hydrocarbons producing heat or fire
Answer: True
◉ Chlorinator rooms must be provided with facilities from
determining the amount of disinfectant used _______
Answer: daily
◉ T/F: Dosage is the amount of chlorine applied in milligrams per
liter or parts per billion.
, Answer: False (parts per million)
◉ DPD reacts with chlorine producing a pink to ____ color.
Answer: red
◉ T/F: Residual is the amount of chlorine left after the demand is
met.
Answer: True (Dosage: How much Cl you put in the system, Demand:
How much Cl is used by the system, Residual: How much Cl is left
over)
◉ T/F: TCEQ requires a faucet for raw water sampling on the
discharge pipe of each PWS well.
Answer: True
◉ Permeability is the ability to _____ water through the aquifer.
Answer: transmit
◉ T/F: The difference between the static level and pumping level is
call the drawdown.
Answer: True
◉ Wells dug into artesian aquifers are considered _____ wells.
CERTIFICATION EXAMINATION 2026
PREMIUM QUESTIONS AND SOLUTIONS
◉ Liquid bleach used in PWS must be ______ approved.
Answer: NSF
◉ T/F: Primary components of a gas feed chlorinator include an
injector, flowrate controller, rotameter, and mixing tank.
Answer: False (injector, vacuum regulator, flowrate controller,
rotameter- *not a mixing tank*)
◉ The maximum sustained gas withdrawal rate for pressure
transmission 150 lb cylinders is ____ lbs/day
Answer: 40
◉ T/F: Utility operators use chlorine in three commercial forms:
1) pure chlorine in the liquid or gas state
2) bleach solutions
3) granular/tablet compounds
Answer: True
,◉ T/F: If chlorine contacts the skin, flush with an emergency shower
or garden hose for at least an hour.
Answer: False (15 minutes)
◉ Hypochlorous acid is the disinfectant and the _____ residual.
Answer: Free
◉ If a major chlorine leak occurs, call the supplier and ______.
Answer: TCEQ
◉ The rotameter indicates the feed rate in _____ per day
Answer: pounds
◉ T/F: Chlorine reacts with hydrocarbons producing heat or fire
Answer: True
◉ Chlorinator rooms must be provided with facilities from
determining the amount of disinfectant used _______
Answer: daily
◉ T/F: Dosage is the amount of chlorine applied in milligrams per
liter or parts per billion.
, Answer: False (parts per million)
◉ DPD reacts with chlorine producing a pink to ____ color.
Answer: red
◉ T/F: Residual is the amount of chlorine left after the demand is
met.
Answer: True (Dosage: How much Cl you put in the system, Demand:
How much Cl is used by the system, Residual: How much Cl is left
over)
◉ T/F: TCEQ requires a faucet for raw water sampling on the
discharge pipe of each PWS well.
Answer: True
◉ Permeability is the ability to _____ water through the aquifer.
Answer: transmit
◉ T/F: The difference between the static level and pumping level is
call the drawdown.
Answer: True
◉ Wells dug into artesian aquifers are considered _____ wells.
