Page | 1
TEXAS CLASS D WATER LICENSE EXAM WITH
100% VERIFIED QUESTIONS AND CORRECT
SOLUTIONS| GUARANTEED PASS| LATEST
2025/2026
1. In the event of low distribution pressure (below 20 psi), water outages,
repeated unacceptable microbiological samples , or failure to maintain
adequate chlorine residuals, special precautions must be instituted by
the? - CORRECT ANSWER - water system
2. In Texas, all public water systems must have ? facilities. -
CORRECT ANSWER - chlorination
3. Chlorination is the most important process in the production of ? water. -
CORRECT ANSWER - potable
4. Calcium hypochlorite will cause explosions or fires if it contacts ?
material. - CORRECT ANSWER - organic
5. At room temperature, chlorine gas is greenish-yellow, has a pungent
odor is ? times heavier than air. - CORRECT ANSWER - 2 1/2
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6. The maximum sustained gas withdrawal rate from 150-lb, cylinders
(vacuum transmissions) is ? lbs(s)./day per degree F. - CORRECT
ANSWER - 1
7. Disinfection capacity for drinking water must be ? % greater than the
highest expected dosage. - CORRECT ANSWER - 50
8. Small water systems often use ? to disinfect their water supply. -
CORRECT ANSWER - hypo chlorinators
9. Hypochlorinators consist of a mixing tank, water, ? hypochlorite, or ?
hypochlorite and a chemical pump. - CORRECT ANSWER -
sodium/calcium
10. Gas chlorinators use a rotameter to meter chlorine in ? or grams/hr. -
CORRECT ANSWER - lbs/day
11. Chlorinator rooms must have ? level and ? level screened vents> -
CORRECT ANSWER - high/floor
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12. In chlorinator rooms, ? must be provided to determine the amount of
disinfectant used and the amount remaining daily. - CORRECT
ANSWER - scales
13. EPA requires any private, municipal, or industrial entity storing or
using ? pounds or more chlorine to have a chemical risk management
program? - CORRECT ANSWER - 2,500
14. Heat-sensitive pressure relief plugs in chlorine containers melt at
about ? degrees F. - CORRECT ANSWER - 160
15. Hold an open bottle of ? % ammonia hydroxide under a suspected
chlorine leak. - CORRECT ANSWER - 10
16. In case of leaks, the best source of help is the? - CORRECT
ANSWER - supplier
17. After contacting chlorine gas, wash in a safety shower or with a? -
CORRECT ANSWER - garden hose
18. What removes tastes, odors, and certain organics and gases, and
oxidizes iron and manganese? This process includes the incorporation
of air into the water by means of spray nozzles , steps or cascades, or
trays of diffusers? - CORRECT ANSWER - Aeration
TEXAS CLASS D WATER LICENSE EXAM WITH
100% VERIFIED QUESTIONS AND CORRECT
SOLUTIONS| GUARANTEED PASS| LATEST
2025/2026
1. In the event of low distribution pressure (below 20 psi), water outages,
repeated unacceptable microbiological samples , or failure to maintain
adequate chlorine residuals, special precautions must be instituted by
the? - CORRECT ANSWER - water system
2. In Texas, all public water systems must have ? facilities. -
CORRECT ANSWER - chlorination
3. Chlorination is the most important process in the production of ? water. -
CORRECT ANSWER - potable
4. Calcium hypochlorite will cause explosions or fires if it contacts ?
material. - CORRECT ANSWER - organic
5. At room temperature, chlorine gas is greenish-yellow, has a pungent
odor is ? times heavier than air. - CORRECT ANSWER - 2 1/2
, Page | 2
6. The maximum sustained gas withdrawal rate from 150-lb, cylinders
(vacuum transmissions) is ? lbs(s)./day per degree F. - CORRECT
ANSWER - 1
7. Disinfection capacity for drinking water must be ? % greater than the
highest expected dosage. - CORRECT ANSWER - 50
8. Small water systems often use ? to disinfect their water supply. -
CORRECT ANSWER - hypo chlorinators
9. Hypochlorinators consist of a mixing tank, water, ? hypochlorite, or ?
hypochlorite and a chemical pump. - CORRECT ANSWER -
sodium/calcium
10. Gas chlorinators use a rotameter to meter chlorine in ? or grams/hr. -
CORRECT ANSWER - lbs/day
11. Chlorinator rooms must have ? level and ? level screened vents> -
CORRECT ANSWER - high/floor
, Page | 3
12. In chlorinator rooms, ? must be provided to determine the amount of
disinfectant used and the amount remaining daily. - CORRECT
ANSWER - scales
13. EPA requires any private, municipal, or industrial entity storing or
using ? pounds or more chlorine to have a chemical risk management
program? - CORRECT ANSWER - 2,500
14. Heat-sensitive pressure relief plugs in chlorine containers melt at
about ? degrees F. - CORRECT ANSWER - 160
15. Hold an open bottle of ? % ammonia hydroxide under a suspected
chlorine leak. - CORRECT ANSWER - 10
16. In case of leaks, the best source of help is the? - CORRECT
ANSWER - supplier
17. After contacting chlorine gas, wash in a safety shower or with a? -
CORRECT ANSWER - garden hose
18. What removes tastes, odors, and certain organics and gases, and
oxidizes iron and manganese? This process includes the incorporation
of air into the water by means of spray nozzles , steps or cascades, or
trays of diffusers? - CORRECT ANSWER - Aeration
