NYC CUSTODIAN ENGINEER EXAM 2026–2027
50 HIGH-YIELD PRACTICE MULTIPLE CHOICE QUESTIONS | VERIFIED ANSWERS & DETAILED
RATIONALES
1. A cleaning team of two workers cleaned four corridors in 24 minutes. Each corridor
measures 12 ft × 176 ft. What is the approximate cleaning rate per man per minute?
A. 150 sq ft
B. 180 sq ft
C. 220 sq ft
D. 260 sq ft
Answer: B
Rationale: Total area is 8,448 sq ft (12 x 176 x 4). Total labor time is 48 man-minutes (2 workers x 24
mins). Rate = 8, = 176 sq ft/min. 180 is the closest option.
2. What is the best time to dust classroom furniture and woodwork?
A. During class
B. After lunch break
C. Before students arrive
D. After school
Answer: C
Rationale: Dusting before arrival ensures that any particulates settled overnight are removed before
student activity disturbs the air, maintaining high Indoor Air Quality (IAQ).
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,3. Which sponge provides the most economical cost per cubic inch?
A. 3×5×7 at $0.90
B. 4×6×10 at $1.30
C. 4×8×12 at $1.44
D. 6×6×6 at $1.20
Answer: C
Rationale: Cost Efficiency = Price / (Length x Width x Height). Option C provides the lowest unit cost
at approximately 0.37 cents per cubic inch.
4. The BEST method for determining cleaning procedures for new surfaces is to:
A. Experiment with chemicals
B. Ask coworkers
C. Use general cleaning methods
D. Follow manufacturer instructions
Answer: D
Rationale: Following the manufacturer’s technical data prevents accidental damage to high-
performance materials and maintains building warranties.
5. Which chemical is MOST effective for removing mildew on terrazzo?
A. Ammonia
B. Sodium hypochlorite
C. Sodium carbonate
D. Vinegar
Answer: B
Rationale: Sodium hypochlorite (bleach) is an oxidative agent that effectively kills fungal spores and
removes microbial stains.
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, 6. Linoleum flooring is composed of:
A. Vinyl materials
B. Asphalt compounds
C. Linseed oil, cork, and resin
D. Rubber and plastic
Answer: C
Rationale: Linoleum is a sustainable, bio-based product. Knowing its organic base (linseed oil) is
critical to avoid high-pH strippers that can cause it to become brittle.
7. The factor LEAST affecting cleaning difficulty is:
A. Surface type
B. Soil type
C. Cleaning agent
D. Time allotted
Answer: D
Rationale: Time allotted affects productivity (volume of work), but it does not change the physical or
chemical difficulty of removing a specific soil from a specific surface.
8. Which is an alkaline cleaning agent?
A. Vinegar
B. Sodium carbonate
C. Hydrochloric acid
D. Alcohol
Answer: B
Rationale: Sodium carbonate (washing soda) is a base (pH > 7) used to saponify organic greases and
oils.
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50 HIGH-YIELD PRACTICE MULTIPLE CHOICE QUESTIONS | VERIFIED ANSWERS & DETAILED
RATIONALES
1. A cleaning team of two workers cleaned four corridors in 24 minutes. Each corridor
measures 12 ft × 176 ft. What is the approximate cleaning rate per man per minute?
A. 150 sq ft
B. 180 sq ft
C. 220 sq ft
D. 260 sq ft
Answer: B
Rationale: Total area is 8,448 sq ft (12 x 176 x 4). Total labor time is 48 man-minutes (2 workers x 24
mins). Rate = 8, = 176 sq ft/min. 180 is the closest option.
2. What is the best time to dust classroom furniture and woodwork?
A. During class
B. After lunch break
C. Before students arrive
D. After school
Answer: C
Rationale: Dusting before arrival ensures that any particulates settled overnight are removed before
student activity disturbs the air, maintaining high Indoor Air Quality (IAQ).
Page 1 of 17
,3. Which sponge provides the most economical cost per cubic inch?
A. 3×5×7 at $0.90
B. 4×6×10 at $1.30
C. 4×8×12 at $1.44
D. 6×6×6 at $1.20
Answer: C
Rationale: Cost Efficiency = Price / (Length x Width x Height). Option C provides the lowest unit cost
at approximately 0.37 cents per cubic inch.
4. The BEST method for determining cleaning procedures for new surfaces is to:
A. Experiment with chemicals
B. Ask coworkers
C. Use general cleaning methods
D. Follow manufacturer instructions
Answer: D
Rationale: Following the manufacturer’s technical data prevents accidental damage to high-
performance materials and maintains building warranties.
5. Which chemical is MOST effective for removing mildew on terrazzo?
A. Ammonia
B. Sodium hypochlorite
C. Sodium carbonate
D. Vinegar
Answer: B
Rationale: Sodium hypochlorite (bleach) is an oxidative agent that effectively kills fungal spores and
removes microbial stains.
Page 2 of 17
, 6. Linoleum flooring is composed of:
A. Vinyl materials
B. Asphalt compounds
C. Linseed oil, cork, and resin
D. Rubber and plastic
Answer: C
Rationale: Linoleum is a sustainable, bio-based product. Knowing its organic base (linseed oil) is
critical to avoid high-pH strippers that can cause it to become brittle.
7. The factor LEAST affecting cleaning difficulty is:
A. Surface type
B. Soil type
C. Cleaning agent
D. Time allotted
Answer: D
Rationale: Time allotted affects productivity (volume of work), but it does not change the physical or
chemical difficulty of removing a specific soil from a specific surface.
8. Which is an alkaline cleaning agent?
A. Vinegar
B. Sodium carbonate
C. Hydrochloric acid
D. Alcohol
Answer: B
Rationale: Sodium carbonate (washing soda) is a base (pH > 7) used to saponify organic greases and
oils.
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