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MINNESOTA SPECIAL ENGINEER BOILER LICENSE
QUESTIONS AND CORRECT ANSWERS WITH
RATIONALES
MINNESOTA SPECIAL ENGINEER BOILER LICENSE
Practice Questions with Answers & Rationales
## EXAM COVERAGE AREAS (MOST TESTED)
1. License Classifications & Scope of Authority (Special Engineer limitations: 50 HP in charge, 100 HP as
shift engineer)
2. Definitions & Classifications (High vs. Low pressure boilers: 15 PSIG steam / 160 PSIG water / 250°F)
3. Boiler Horsepower Calculations (10 sq ft heating surface = 1 HP; 67,000 BTU/hr = 1 HP; 10 kW = 1 HP)
4. Safety Devices (LWCO, safety valves, pressuretrols, aquastats, Tri indicators)
5. Water Columns & Gauge Glasses (Blowdown procedure, frequency, materials)
6. Combustion & Draft Systems (Natural, forced, induced, balanced draft; efficiency indicators)
7. Water Treatment (Scale, caustic embrittlement, chelants, polymers, pH range 7-11)
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8. Feedwater Systems (Deaerators, condensate return, two means of feedwater for >50 HP)
9. Hot Water Boiler Systems (Expansion tanks, aquastats, Tri indicators, thermal shock prevention)
10. Operational Procedures & Safety (Kill switches, lockout/tagout, logbooks, hydrostatic testing)
---
### QUESTIONS 1-250
1. According to Minnesota Statute, what is the maximum total boiler horsepower a person holding a
Special Engineer License can be in charge of as the chief operator of a plant?
A) 100 boiler horsepower total in any plant configuration
B) 50 boiler horsepower total in high and low pressure plants
C) 500 boiler horsepower total with proper supervision
D) 25 boiler horsepower total for steam boilers only
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Answer: B - A Special Engineer can take charge of boilers not exceeding 50 total boiler horsepower, or
serve as a shift engineer in a plant not exceeding 100 horsepower .
2. What is the legal definition of a low-pressure boiler according to Minnesota statutes and boiler code
regulations?
A) Any boiler operating at a steam pressure of 100 psig or less
B) Boilers at 15 psig steam or less, or water boilers under 160 psig and 250°F
C) Boilers that operate at atmospheric pressure only
D) Any boiler with a heating surface less than 100 square feet
Answer: B - Low-pressure boilers are defined as steam boilers at 15 PSIG or less, or hot water boilers
where pressure does not exceed 160 PSIG or temperature 250°F .
3. For the purpose of rating boiler horsepower for engineer license classifications in Minnesota, how
many square feet of heating surface equal one boiler horsepower?
A) 5 square feet of heating surface per horsepower
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B) 10 square feet of heating surface per horsepower
C) 15 square feet of heating surface per horsepower
D) 20 square feet of heating surface per horsepower
Answer: B - Minnesota statutes specify 10 square feet of heating surface equals one boiler horsepower
for conventional boilers, and 5 square feet for steam coil type generators .
4. A person holding a current State of Minnesota Special Engineer License can serve as an apprentice in
what size plant and under what conditions?
A) Only in plants of 50 horsepower or less
B) Only in plants of 100 horsepower or less
C) In any plant regardless of size under direct supervision of a properly licensed engineer
D) Only in low-pressure plants of any size
Answer: C - A Special Engineer may serve as an apprentice in any size plant when under the direct
supervision of a properly licensed engineer, regardless of the plant's horsepower rating .
MINNESOTA SPECIAL ENGINEER BOILER LICENSE
QUESTIONS AND CORRECT ANSWERS WITH
RATIONALES
MINNESOTA SPECIAL ENGINEER BOILER LICENSE
Practice Questions with Answers & Rationales
## EXAM COVERAGE AREAS (MOST TESTED)
1. License Classifications & Scope of Authority (Special Engineer limitations: 50 HP in charge, 100 HP as
shift engineer)
2. Definitions & Classifications (High vs. Low pressure boilers: 15 PSIG steam / 160 PSIG water / 250°F)
3. Boiler Horsepower Calculations (10 sq ft heating surface = 1 HP; 67,000 BTU/hr = 1 HP; 10 kW = 1 HP)
4. Safety Devices (LWCO, safety valves, pressuretrols, aquastats, Tri indicators)
5. Water Columns & Gauge Glasses (Blowdown procedure, frequency, materials)
6. Combustion & Draft Systems (Natural, forced, induced, balanced draft; efficiency indicators)
7. Water Treatment (Scale, caustic embrittlement, chelants, polymers, pH range 7-11)
, Page 2 of 137
8. Feedwater Systems (Deaerators, condensate return, two means of feedwater for >50 HP)
9. Hot Water Boiler Systems (Expansion tanks, aquastats, Tri indicators, thermal shock prevention)
10. Operational Procedures & Safety (Kill switches, lockout/tagout, logbooks, hydrostatic testing)
---
### QUESTIONS 1-250
1. According to Minnesota Statute, what is the maximum total boiler horsepower a person holding a
Special Engineer License can be in charge of as the chief operator of a plant?
A) 100 boiler horsepower total in any plant configuration
B) 50 boiler horsepower total in high and low pressure plants
C) 500 boiler horsepower total with proper supervision
D) 25 boiler horsepower total for steam boilers only
, Page 3 of 137
Answer: B - A Special Engineer can take charge of boilers not exceeding 50 total boiler horsepower, or
serve as a shift engineer in a plant not exceeding 100 horsepower .
2. What is the legal definition of a low-pressure boiler according to Minnesota statutes and boiler code
regulations?
A) Any boiler operating at a steam pressure of 100 psig or less
B) Boilers at 15 psig steam or less, or water boilers under 160 psig and 250°F
C) Boilers that operate at atmospheric pressure only
D) Any boiler with a heating surface less than 100 square feet
Answer: B - Low-pressure boilers are defined as steam boilers at 15 PSIG or less, or hot water boilers
where pressure does not exceed 160 PSIG or temperature 250°F .
3. For the purpose of rating boiler horsepower for engineer license classifications in Minnesota, how
many square feet of heating surface equal one boiler horsepower?
A) 5 square feet of heating surface per horsepower
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B) 10 square feet of heating surface per horsepower
C) 15 square feet of heating surface per horsepower
D) 20 square feet of heating surface per horsepower
Answer: B - Minnesota statutes specify 10 square feet of heating surface equals one boiler horsepower
for conventional boilers, and 5 square feet for steam coil type generators .
4. A person holding a current State of Minnesota Special Engineer License can serve as an apprentice in
what size plant and under what conditions?
A) Only in plants of 50 horsepower or less
B) Only in plants of 100 horsepower or less
C) In any plant regardless of size under direct supervision of a properly licensed engineer
D) Only in low-pressure plants of any size
Answer: C - A Special Engineer may serve as an apprentice in any size plant when under the direct
supervision of a properly licensed engineer, regardless of the plant's horsepower rating .
