BOMI: AIR HANDLING, WATER TREATMENT &
PLUMBING SYSTEMS EXAM 2026/2027 450 ACCURATE
QUESTIONS WITH DETAILED VERIFIED ANSWERS ALL
CHAPTERS COVERED | 100% CORRECT ANSWERS |
ALREADY GRADED A+ COMPLETE STUDY GUIDE FOR
CERTIFICATION LATEST UPDATE
Topics Covered:
- Air Handling Systems (Duct Design, Fans, Filters, HVAC Components)
- Water Treatment (Boilers, Cooling Towers, Corrosion Control, Chemical Programs)
- Plumbing Systems (Pipes, Fixtures, Water Heating, Drainage, Codes)
SECTION 1: DUCT SYSTEMS AND MATERIALS (Questions 1–50)
Question 1
What is a problem with using fibrous glass wool as duct-work material?
A) It is too expensive for most applications
B) It requires specialized installation tools
C) The World Health Organization has declared fibrous glass wool as
carcinogenic to humans; cannot use it in hospitals or kitchens
D) It has poor thermal insulation properties
Answer: C
Rationale: The World Health Organization has classified fibrous glass wool as
carcinogenic to humans. Due to health concerns, it cannot be used in hospitals
or kitchens where airborne fibers could pose a risk to occupants.
Question 2
This type of material is used in low-pressure and low-velocity duct systems.
They have high friction.
A) Galvanized steel duct
B) Aluminum duct
1
,C) Flexible duct
D) Fibrous glass duct
Answer: C
Rationale: Flexible duct is commonly used in low-pressure and low-velocity
systems. Its corrugated interior creates higher friction loss compared to
smooth-walled rigid ducts, which is why it is limited to low-pressure
applications.
Question 3
Which type of duct uses fiberglass insulation?
A) Galvanized steel duct
B) Flexible duct
C) Rigid fiberglass duct
D) Stainless steel duct
Answer: B
Rationale: Flexible duct typically consists of a wire helix covered with
fiberglass insulation and a vapor barrier. The fiberglass provides both
thermal insulation and sound attenuation.
Question 4
How can duct leakage be eliminated?
A) By using thicker gauge metal
B) Through use of sealants applied to all duct joints, duct collar tap-ins,
branch intersections, access doors, and air terminal connections
C) By increasing the duct size
D) By reducing the air velocity
Answer: B
Rationale: Duct leakage can be effectively eliminated by applying sealants
2
,to all potential leak points including duct joints, duct collar tap-ins,
branch intersections, access doors, and air terminal connections. Proper
sealing is essential for energy efficiency and system performance.
Question 5
Generally, how long can a duct be before it needs to be insulated?
A) 25 feet
B) 50 feet
C) 75 feet
D) 100 feet
Answer: B
Rationale: Generally, ducts longer than 50 feet should be insulated to prevent
excessive heat gain or loss. Insulation length requirements also depend on the
temperature differential and the space conditions.
Question 6
Which is the simplest, but least accurate pH test?
A) Digital pH meter
B) pH paper
C) Titration test
D) Colorimetric comparator
Answer: B
Rationale: pH paper (litmus paper) is the simplest pH testing method, but it
is also the least accurate, typically providing results within ±0.5 pH units.
It provides a quick visual indication but lacks precision for critical
applications.
Question 7
3
, What is the recommended maximum air velocity in a main supply duct?
A) 500-1000 FPM
B) 1000-2000 FPM
C) 2000-3000 FPM
D) 3000-4000 FPM
Answer: B
Rationale: Recommended maximum air velocities for main supply ducts are
typically 1000-2000 FPM (feet per minute). Higher velocities increase noise
and friction losses, while lower velocities require larger duct sizes and
higher costs.
Question 8
What is the purpose of duct insulation?
A) To reduce noise only
B) To prevent condensation and reduce heat loss/gain
C) To increase air velocity
D) To decrease static pressure
Answer: B
Rationale: Duct insulation serves multiple purposes including preventing
condensation on cold ducts (which can lead to mold and water damage),
reducing heat loss from hot ducts, and minimizing heat gain in cold air
distribution systems. It also provides some sound attenuation.
Question 9
Which type of duct material is most commonly used in commercial HVAC
systems?
A) Aluminum
B) Copper
C) Galvanized steel
4
PLUMBING SYSTEMS EXAM 2026/2027 450 ACCURATE
QUESTIONS WITH DETAILED VERIFIED ANSWERS ALL
CHAPTERS COVERED | 100% CORRECT ANSWERS |
ALREADY GRADED A+ COMPLETE STUDY GUIDE FOR
CERTIFICATION LATEST UPDATE
Topics Covered:
- Air Handling Systems (Duct Design, Fans, Filters, HVAC Components)
- Water Treatment (Boilers, Cooling Towers, Corrosion Control, Chemical Programs)
- Plumbing Systems (Pipes, Fixtures, Water Heating, Drainage, Codes)
SECTION 1: DUCT SYSTEMS AND MATERIALS (Questions 1–50)
Question 1
What is a problem with using fibrous glass wool as duct-work material?
A) It is too expensive for most applications
B) It requires specialized installation tools
C) The World Health Organization has declared fibrous glass wool as
carcinogenic to humans; cannot use it in hospitals or kitchens
D) It has poor thermal insulation properties
Answer: C
Rationale: The World Health Organization has classified fibrous glass wool as
carcinogenic to humans. Due to health concerns, it cannot be used in hospitals
or kitchens where airborne fibers could pose a risk to occupants.
Question 2
This type of material is used in low-pressure and low-velocity duct systems.
They have high friction.
A) Galvanized steel duct
B) Aluminum duct
1
,C) Flexible duct
D) Fibrous glass duct
Answer: C
Rationale: Flexible duct is commonly used in low-pressure and low-velocity
systems. Its corrugated interior creates higher friction loss compared to
smooth-walled rigid ducts, which is why it is limited to low-pressure
applications.
Question 3
Which type of duct uses fiberglass insulation?
A) Galvanized steel duct
B) Flexible duct
C) Rigid fiberglass duct
D) Stainless steel duct
Answer: B
Rationale: Flexible duct typically consists of a wire helix covered with
fiberglass insulation and a vapor barrier. The fiberglass provides both
thermal insulation and sound attenuation.
Question 4
How can duct leakage be eliminated?
A) By using thicker gauge metal
B) Through use of sealants applied to all duct joints, duct collar tap-ins,
branch intersections, access doors, and air terminal connections
C) By increasing the duct size
D) By reducing the air velocity
Answer: B
Rationale: Duct leakage can be effectively eliminated by applying sealants
2
,to all potential leak points including duct joints, duct collar tap-ins,
branch intersections, access doors, and air terminal connections. Proper
sealing is essential for energy efficiency and system performance.
Question 5
Generally, how long can a duct be before it needs to be insulated?
A) 25 feet
B) 50 feet
C) 75 feet
D) 100 feet
Answer: B
Rationale: Generally, ducts longer than 50 feet should be insulated to prevent
excessive heat gain or loss. Insulation length requirements also depend on the
temperature differential and the space conditions.
Question 6
Which is the simplest, but least accurate pH test?
A) Digital pH meter
B) pH paper
C) Titration test
D) Colorimetric comparator
Answer: B
Rationale: pH paper (litmus paper) is the simplest pH testing method, but it
is also the least accurate, typically providing results within ±0.5 pH units.
It provides a quick visual indication but lacks precision for critical
applications.
Question 7
3
, What is the recommended maximum air velocity in a main supply duct?
A) 500-1000 FPM
B) 1000-2000 FPM
C) 2000-3000 FPM
D) 3000-4000 FPM
Answer: B
Rationale: Recommended maximum air velocities for main supply ducts are
typically 1000-2000 FPM (feet per minute). Higher velocities increase noise
and friction losses, while lower velocities require larger duct sizes and
higher costs.
Question 8
What is the purpose of duct insulation?
A) To reduce noise only
B) To prevent condensation and reduce heat loss/gain
C) To increase air velocity
D) To decrease static pressure
Answer: B
Rationale: Duct insulation serves multiple purposes including preventing
condensation on cold ducts (which can lead to mold and water damage),
reducing heat loss from hot ducts, and minimizing heat gain in cold air
distribution systems. It also provides some sound attenuation.
Question 9
Which type of duct material is most commonly used in commercial HVAC
systems?
A) Aluminum
B) Copper
C) Galvanized steel
4
