NEWEST WATER QUALITY LABORATORY
ANALYST CERTIFICATION EXAM OFFERED BY
CA‑NV SECTION OF THE AMERICAN WATER
WORKS ASSOCIATION | COMPLETE EXAM Q&A
WITH RATIONALES
**1.** According to the Safe Drinking Water Act
(SDWA), what is the Maximum Contaminant Level
Goal (MCLG)?
A) The enforceable limit set as close to the MCLG as
feasible
B) The maximum permissible level of a contaminant in
water delivered to any user of a public water system
C) The level of a contaminant in drinking water below
which there is no known or expected risk to health
D) The highest concentration of a contaminant that is
allowed in drinking water
Correct answer: C
Rationale: MCLG is a non‑enforceable health‑based
goal set at a level with no known or expected adverse
health effects, allowing an adequate margin of safety.
,**2.** In a drinking water laboratory, which class of
chemicals requires storage in a flammable safety
cabinet?
A) Corrosive acids
B) Oxidizers
C) Flammable liquids with a flash point below 100°F
(37.8°C)
D) Toxic solids
Correct answer: C
Rationale: Flammable liquids with a flash point below
100°F must be stored in approved flammable storage
cabinets to reduce fire risk.
**3.** What is the correct formula for calculating
percent recovery in a matrix spike sample?
A) (Spiked result − Unspiked result) ÷ Spike
concentration × 100
B) Unspiked result ÷ Spiked result × 100
C) Spike concentration ÷ Spiked result × 100
,D) Spiked result ÷ Unspiked result × 100
Correct answer: A
Rationale: Percent recovery evaluates the accuracy
of an analytical method in a specific sample matrix.
**4.** In the EDTA titrimetric method for total
hardness, which indicator is commonly used at pH
10?
A) Phenolphthalein
B) Eriochrome Black T
C) Starch
D) Potassium chromate
Correct answer: B
Rationale: Eriochrome Black T is wine‑red in the
presence of Ca²⁺ and Mg²⁺ at pH 10 and turns blue
when all hardness ions are complexed by EDTA.
**5.** A 1.0 g/L standard solution is diluted 10‑fold.
What is the final concentration in mg/L?
, A) 10 mg/L
B) 100 mg/L
C) 500 mg/L
D) 1000 mg/L
Correct answer: B
Rationale: 1.0 g/L = 1000 mg/L. A 10‑fold dilution
gives 100 mg/L.
**6.** ASTM Type I reagent water must have a
conductivity of less than:
A) 0.1 µS/cm
B) 0.2 µS/cm
C) 1.0 µS/cm
D) 2.0 µS/cm
Correct answer: A
Rationale: ASTM Type I water requires conductivity ≤
0.1 µS/cm (or resistivity ≥ 10 MΩ·cm) at 25°C.
ANALYST CERTIFICATION EXAM OFFERED BY
CA‑NV SECTION OF THE AMERICAN WATER
WORKS ASSOCIATION | COMPLETE EXAM Q&A
WITH RATIONALES
**1.** According to the Safe Drinking Water Act
(SDWA), what is the Maximum Contaminant Level
Goal (MCLG)?
A) The enforceable limit set as close to the MCLG as
feasible
B) The maximum permissible level of a contaminant in
water delivered to any user of a public water system
C) The level of a contaminant in drinking water below
which there is no known or expected risk to health
D) The highest concentration of a contaminant that is
allowed in drinking water
Correct answer: C
Rationale: MCLG is a non‑enforceable health‑based
goal set at a level with no known or expected adverse
health effects, allowing an adequate margin of safety.
,**2.** In a drinking water laboratory, which class of
chemicals requires storage in a flammable safety
cabinet?
A) Corrosive acids
B) Oxidizers
C) Flammable liquids with a flash point below 100°F
(37.8°C)
D) Toxic solids
Correct answer: C
Rationale: Flammable liquids with a flash point below
100°F must be stored in approved flammable storage
cabinets to reduce fire risk.
**3.** What is the correct formula for calculating
percent recovery in a matrix spike sample?
A) (Spiked result − Unspiked result) ÷ Spike
concentration × 100
B) Unspiked result ÷ Spiked result × 100
C) Spike concentration ÷ Spiked result × 100
,D) Spiked result ÷ Unspiked result × 100
Correct answer: A
Rationale: Percent recovery evaluates the accuracy
of an analytical method in a specific sample matrix.
**4.** In the EDTA titrimetric method for total
hardness, which indicator is commonly used at pH
10?
A) Phenolphthalein
B) Eriochrome Black T
C) Starch
D) Potassium chromate
Correct answer: B
Rationale: Eriochrome Black T is wine‑red in the
presence of Ca²⁺ and Mg²⁺ at pH 10 and turns blue
when all hardness ions are complexed by EDTA.
**5.** A 1.0 g/L standard solution is diluted 10‑fold.
What is the final concentration in mg/L?
, A) 10 mg/L
B) 100 mg/L
C) 500 mg/L
D) 1000 mg/L
Correct answer: B
Rationale: 1.0 g/L = 1000 mg/L. A 10‑fold dilution
gives 100 mg/L.
**6.** ASTM Type I reagent water must have a
conductivity of less than:
A) 0.1 µS/cm
B) 0.2 µS/cm
C) 1.0 µS/cm
D) 2.0 µS/cm
Correct answer: A
Rationale: ASTM Type I water requires conductivity ≤
0.1 µS/cm (or resistivity ≥ 10 MΩ·cm) at 25°C.
