661-LA 661 Louisiana (New Orleans) Second Class Stationary Boilers
Practice Exam 200 Questions and Correct Answers Based on New
Orleans Boiler Code and ASME Standards 2026 Edition
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About the 661-LA Second Class Stationary Boiler Exam
The 661-LA Second Class Stationary Boilers Exam is required for individuals seeking certification
to operate and maintain stationary boiler systems in New Orleans. Candidates must
demonstrate knowledge of boiler operations, safety procedures, water treatment, and
applicable codes .
Key Exam Information:
- Administered by the Board of Examiners of Steam Boilers for municipalities over 50,000
inhabitants
- Certificates must be conspicuously posted in engine rooms
- Renewals required annually
- Exam covers water treatment, combustion, safety devices, piping systems, and maintenance
procedures
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SECTION 1: WATER SUPPLY TREATMENT AND FEED SYSTEMS (Questions 1-45)
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,Question 1
Which water quality parameter is most critical in causing scale formation in boiler systems?
A) pH
B) Hardness (mineral content)
C) Alkalinity
D) Conductivity
Correct Answer: B) Hardness (mineral content)
Rationale: High levels of calcium and magnesium (i.e., hardness) precipitate as scale on heat
transfer surfaces. Scale acts as an insulator, reducing heat transfer efficiency and potentially
causing tube overheating and failure .
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Question 2
What is the primary purpose of a deaerator in a boiler feed system?
A) Increase feedwater pressure
B) Remove dissolved oxygen
C) Adjust water pH
D) Remove scale particles
Correct Answer: B) Remove dissolved oxygen
,Rationale: Deaerators remove dissolved oxygen, reducing corrosion risks in the boiler. Oxygen is
the primary cause of pitting corrosion in boiler systems, leading to premature tube failure .
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Question 3
Which chemical is most commonly added to boiler water to control scale formation?
A) Sodium bisulfite
B) Polyphosphate (Phosphates)
C) Chlorine
D) Ammonia
Correct Answer: B) Polyphosphate (Phosphates)
Rationale: Polyphosphates bind hardness ions (calcium and magnesium) and prevent them from
precipitating as scale on heat transfer surfaces .
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Question 4
What is "carryover" in boiler operation?
A) Water droplets carried with steam
, B) Excess chemical additives
C) Unburned fuel particles in flue gas
D) Scale deposits on boiler tubes
Correct Answer: A) Water droplets carried with steam
Rationale: Carryover refers to water droplets that are carried with the steam, affecting steam
quality. This can cause fouling of downstream equipment and may indicate excessive dissolved
solids or improper chemical treatment .
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Question 5
Maintaining which parameter is crucial for preventing corrosion in boiler water?
A) High conductivity
B) Low dissolved oxygen
C) High pH fluctuations
D) Elevated hardness
Correct Answer: B) Low dissolved oxygen
Rationale: Low dissolved oxygen levels minimize corrosion of boiler metal surfaces. Oxygen
pitting is one of the most common and destructive forms of boiler corrosion .
---
Practice Exam 200 Questions and Correct Answers Based on New
Orleans Boiler Code and ASME Standards 2026 Edition
---
About the 661-LA Second Class Stationary Boiler Exam
The 661-LA Second Class Stationary Boilers Exam is required for individuals seeking certification
to operate and maintain stationary boiler systems in New Orleans. Candidates must
demonstrate knowledge of boiler operations, safety procedures, water treatment, and
applicable codes .
Key Exam Information:
- Administered by the Board of Examiners of Steam Boilers for municipalities over 50,000
inhabitants
- Certificates must be conspicuously posted in engine rooms
- Renewals required annually
- Exam covers water treatment, combustion, safety devices, piping systems, and maintenance
procedures
---
SECTION 1: WATER SUPPLY TREATMENT AND FEED SYSTEMS (Questions 1-45)
---
,Question 1
Which water quality parameter is most critical in causing scale formation in boiler systems?
A) pH
B) Hardness (mineral content)
C) Alkalinity
D) Conductivity
Correct Answer: B) Hardness (mineral content)
Rationale: High levels of calcium and magnesium (i.e., hardness) precipitate as scale on heat
transfer surfaces. Scale acts as an insulator, reducing heat transfer efficiency and potentially
causing tube overheating and failure .
---
Question 2
What is the primary purpose of a deaerator in a boiler feed system?
A) Increase feedwater pressure
B) Remove dissolved oxygen
C) Adjust water pH
D) Remove scale particles
Correct Answer: B) Remove dissolved oxygen
,Rationale: Deaerators remove dissolved oxygen, reducing corrosion risks in the boiler. Oxygen is
the primary cause of pitting corrosion in boiler systems, leading to premature tube failure .
---
Question 3
Which chemical is most commonly added to boiler water to control scale formation?
A) Sodium bisulfite
B) Polyphosphate (Phosphates)
C) Chlorine
D) Ammonia
Correct Answer: B) Polyphosphate (Phosphates)
Rationale: Polyphosphates bind hardness ions (calcium and magnesium) and prevent them from
precipitating as scale on heat transfer surfaces .
---
Question 4
What is "carryover" in boiler operation?
A) Water droplets carried with steam
, B) Excess chemical additives
C) Unburned fuel particles in flue gas
D) Scale deposits on boiler tubes
Correct Answer: A) Water droplets carried with steam
Rationale: Carryover refers to water droplets that are carried with the steam, affecting steam
quality. This can cause fouling of downstream equipment and may indicate excessive dissolved
solids or improper chemical treatment .
---
Question 5
Maintaining which parameter is crucial for preventing corrosion in boiler water?
A) High conductivity
B) Low dissolved oxygen
C) High pH fluctuations
D) Elevated hardness
Correct Answer: B) Low dissolved oxygen
Rationale: Low dissolved oxygen levels minimize corrosion of boiler metal surfaces. Oxygen
pitting is one of the most common and destructive forms of boiler corrosion .
---
