NEWEST CERTIFIED WATER TECHNOLOGIST
(CWT) CERTIFICATION EXAM OFFERED BY
ASSOCIATION OF WATER TECHNOLOGIES |
COMPLETE EXAM Q&A WITH RATIONALES
**1.** A fresh water sample has total alkalinity higher
than total hardness. This indicates:
A) All hardness is in the bicarbonate form
B) No hardness is in the bicarbonate form
C) Some hardness is in the carbonate form
D) All hardness is in the carbonate form
Correct answer: D
Rationale: When alkalinity exceeds hardness, all
hardness is in the carbonate form.
**2.** To calculate boiler blowdown heat recovery
savings, which value is essential?
A) Make-up water temperature
B) Thermal losses due to deposits
C) BTU content of fuel
D) Condensate temperature
Correct answer: C
,Rationale: Blowdown heat recovery savings depend
on knowing the fuel cost, which is derived from BTU
content.
**3.** A boiler cycles feedwater eight times. The
percent blowdown is:
A) 8%
B) 12.5%
C) 15%
D) 17.5%
Correct answer: B
Rationale: Blowdown % = 100% ÷ Cycles. 100% ÷ 8 =
12.5%.
**4.** The normal bed depth in a standard ion
exchange water softener is:
A) 24 inches
B) 36 inches
C) 42 inches
D) 48 inches
Correct answer: B
Rationale: The typical resin bed depth in a
conventional softener is 36 inches.
,**5.** Which coagulant operates best at pH 6.8?
A) Aluminum sulfate (alum)
B) Ferric sulfate
C) Ferric chloride
D) Aluminum chloride
Correct answer: A
Rationale: Aluminum sulfate (alum) has an optimal
coagulation pH range around 6.0-7.0.
**6.** In a gravity feed condensate return system,
adequate _____ prevents condensate from hanging
up.
A) Separators
B) Pitch
C) Traps
D) Treatment
Correct answer: B
Rationale: Proper slope (pitch) ensures gravity flow;
reverse slope causes hang-up.
, **7.** Which material requires the most frequent
replacement as a sacrificial anode in cooling water?
A) Aluminum
B) Magnesium
C) Cadmium
D) Zinc
Correct answer: B
Rationale: Magnesium is highly active and corrodes
quickly, requiring frequent replacement.
**8.** A recommended copper corrosion inhibitor for
closed systems is:
A) DEHA
B) Sulfite
C) Nitrite
D) Tolyltriazole (TT)
Correct answer: D
Rationale: Tolyltriazole (TT) and benzotriazole (BZT)
are specific copper corrosion inhibitors for closed
loops.
**9.** A Safety Data Sheet (SDS) must contain:
(CWT) CERTIFICATION EXAM OFFERED BY
ASSOCIATION OF WATER TECHNOLOGIES |
COMPLETE EXAM Q&A WITH RATIONALES
**1.** A fresh water sample has total alkalinity higher
than total hardness. This indicates:
A) All hardness is in the bicarbonate form
B) No hardness is in the bicarbonate form
C) Some hardness is in the carbonate form
D) All hardness is in the carbonate form
Correct answer: D
Rationale: When alkalinity exceeds hardness, all
hardness is in the carbonate form.
**2.** To calculate boiler blowdown heat recovery
savings, which value is essential?
A) Make-up water temperature
B) Thermal losses due to deposits
C) BTU content of fuel
D) Condensate temperature
Correct answer: C
,Rationale: Blowdown heat recovery savings depend
on knowing the fuel cost, which is derived from BTU
content.
**3.** A boiler cycles feedwater eight times. The
percent blowdown is:
A) 8%
B) 12.5%
C) 15%
D) 17.5%
Correct answer: B
Rationale: Blowdown % = 100% ÷ Cycles. 100% ÷ 8 =
12.5%.
**4.** The normal bed depth in a standard ion
exchange water softener is:
A) 24 inches
B) 36 inches
C) 42 inches
D) 48 inches
Correct answer: B
Rationale: The typical resin bed depth in a
conventional softener is 36 inches.
,**5.** Which coagulant operates best at pH 6.8?
A) Aluminum sulfate (alum)
B) Ferric sulfate
C) Ferric chloride
D) Aluminum chloride
Correct answer: A
Rationale: Aluminum sulfate (alum) has an optimal
coagulation pH range around 6.0-7.0.
**6.** In a gravity feed condensate return system,
adequate _____ prevents condensate from hanging
up.
A) Separators
B) Pitch
C) Traps
D) Treatment
Correct answer: B
Rationale: Proper slope (pitch) ensures gravity flow;
reverse slope causes hang-up.
, **7.** Which material requires the most frequent
replacement as a sacrificial anode in cooling water?
A) Aluminum
B) Magnesium
C) Cadmium
D) Zinc
Correct answer: B
Rationale: Magnesium is highly active and corrodes
quickly, requiring frequent replacement.
**8.** A recommended copper corrosion inhibitor for
closed systems is:
A) DEHA
B) Sulfite
C) Nitrite
D) Tolyltriazole (TT)
Correct answer: D
Rationale: Tolyltriazole (TT) and benzotriazole (BZT)
are specific copper corrosion inhibitors for closed
loops.
**9.** A Safety Data Sheet (SDS) must contain:
