Page 1 of 105
Arizona C-74 Boilers, Steamfitting & Process Piping EXAM
QUESTIONS AND CORRECT VERIFIED SOLUTIONS LATEST
UPDATE THIS YEAR – JUST RELEASED
Arizona C-74 Boilers, Steamfitting & Process Piping Exam
10-Line Exam Coverage in Points Form
1. Exam Logistics & Scope - 80 questions, 3-hour time limit, 70% passing score, closed-
book format administered by PSI; scope includes installation, alteration, and repair of
steam/hot water systems, boilers, process piping, and solar thermal equipment
2. License Classifications - C-74 (Commercial), CR-74 (Dual - both commercial and
residential), L-4 classification; requires 2 years experience without trade exam or 0 years
with exam; application fee $580, bond requirements up to $37,500 based on annual
volume
3. Steam/Hot Water Piping - Largest exam topic (19-20%); condensate receivers (collect
and store condensate for return to boiler), float traps (condensate removal), expansion
loops (absorb thermal expansion), and globe valves (throttling steam flow)
4. Boiler Systems - Firetube vs. watertube boilers; economizers (preheat feedwater using
flue gas heat); pressuretrol (pressure control); aquastat (temperature control); safety
relief valve testing; low-water cutoff protection
5. Process Piping & Materials - ASME B31.1 (power piping) governs high-pressure systems;
butt-welded joints for high-pressure large-diameter lines; flanges for connections
allowing disassembly; hydrostatic testing at 1.5× design pressure
6. Combustion & Burners - Atmospheric vs. power burners (internal fan for combustion
air); barometric dampers (maintain draft); burners (10% of exam); fuel piping/storage
(10-11%)
7. Controls & Safety Devices - ASME CSD-1 controls and safety devices; PLCs
(programmable logic controllers) automate process controls; feedback control loops
maintain setpoints; pressure-limit controls (shut down boiler at over-pressure)
8. Solar Thermal Systems - 5% of exam; propylene glycol for freeze protection (non-toxic);
collector tilt angle ≈ latitude (33° for Phoenix); evacuated-tube collectors (better
cold/cloudy weather performance); heat exchanger transfers collector heat
9. Flues, Vents & Combustion Air - 10-11% of exam; Category III appliances (≥8 inch vent
diameter for higher heat input); power venting for Category IV appliances (positive
pressure); louvers (prevent rain ingress while allowing airflow)
, Page 2 of 105
10. Codes, Safety & References - IMC 2006, IFGC 2006, ASME CSD-1-2006, Arizona Boiler
Rules; OSHA 1926 safety (PPE, confined space entry, trenching); references used to
create questions but NOT allowed in testing center
100 MCQ Questions with Rationales
1. What is the primary scope of work permitted under an Arizona C-74 Boilers, Steamfitting
and Process Piping license?
A) Installation of new electrical service panels only
B) Installation, alteration, and repair of steam and hot water systems, boilers, process piping,
and solar equipment
C) Plumbing installation for all building systems
D) Full electrical wiring for all building circuits
Correct Answer: B
Rationale: The C-74 license covers installation, alteration, and repair of steam and hot water
systems and boilers, including chimney connections, flues, refractories, burners, piping, fittings,
valves, thermal insulation, accessories, process piping, and solar equipment .
2. What electrical work is a C-74 licensee permitted to perform?
A) Installation of a new main service panel
B) Installation of a new sub-panel
C) Adding a new circuit to an existing service panel or sub-panel
D) Full electrical service upgrades
, Page 3 of 105
Correct Answer: C
Rationale: A C-74 licensee may add a new circuit to an existing service panel or sub-panel.
Installation of a new service panel or sub-panel is specifically excluded from scope .
3. How many questions are on the Arizona C-74 examination?
A) 50
B) 60
C) 80
D) 100
Correct Answer: C
Rationale: The C-74 exam consists of 80 questions .
4. What is the time limit for completing the Arizona C-74 exam?
A) 2 hours
B) 2.5 hours
C) 3 hours
D) 4 hours
Correct Answer: C
Rationale: The C-74 exam has a 3-hour time limit .
5. What is the passing score for the Arizona C-74 examination?
A) 65%
B) 70%
, Page 4 of 105
C) 75%
D) 80%
Correct Answer: B
Rationale: The C-74 exam requires a score of 70% correct to pass .
6. What percentage of the C-74 exam covers Steam/Hot Water Piping?
A) 10%
B) 15%
C) 19-20%
D) 25%
Correct Answer: C
Rationale: Steam/Hot Water Piping comprises 19-20% of the exam content, making it the largest
topic area .
7. What percentage of the C-74 exam covers Boilers?
A) 5%
B) 10%
C) 15%
D) 20%
Correct Answer: B
Rationale: The Boilers topic comprises 10% of the exam .
8. What percentage of the C-74 exam covers Solar?
Arizona C-74 Boilers, Steamfitting & Process Piping EXAM
QUESTIONS AND CORRECT VERIFIED SOLUTIONS LATEST
UPDATE THIS YEAR – JUST RELEASED
Arizona C-74 Boilers, Steamfitting & Process Piping Exam
10-Line Exam Coverage in Points Form
1. Exam Logistics & Scope - 80 questions, 3-hour time limit, 70% passing score, closed-
book format administered by PSI; scope includes installation, alteration, and repair of
steam/hot water systems, boilers, process piping, and solar thermal equipment
2. License Classifications - C-74 (Commercial), CR-74 (Dual - both commercial and
residential), L-4 classification; requires 2 years experience without trade exam or 0 years
with exam; application fee $580, bond requirements up to $37,500 based on annual
volume
3. Steam/Hot Water Piping - Largest exam topic (19-20%); condensate receivers (collect
and store condensate for return to boiler), float traps (condensate removal), expansion
loops (absorb thermal expansion), and globe valves (throttling steam flow)
4. Boiler Systems - Firetube vs. watertube boilers; economizers (preheat feedwater using
flue gas heat); pressuretrol (pressure control); aquastat (temperature control); safety
relief valve testing; low-water cutoff protection
5. Process Piping & Materials - ASME B31.1 (power piping) governs high-pressure systems;
butt-welded joints for high-pressure large-diameter lines; flanges for connections
allowing disassembly; hydrostatic testing at 1.5× design pressure
6. Combustion & Burners - Atmospheric vs. power burners (internal fan for combustion
air); barometric dampers (maintain draft); burners (10% of exam); fuel piping/storage
(10-11%)
7. Controls & Safety Devices - ASME CSD-1 controls and safety devices; PLCs
(programmable logic controllers) automate process controls; feedback control loops
maintain setpoints; pressure-limit controls (shut down boiler at over-pressure)
8. Solar Thermal Systems - 5% of exam; propylene glycol for freeze protection (non-toxic);
collector tilt angle ≈ latitude (33° for Phoenix); evacuated-tube collectors (better
cold/cloudy weather performance); heat exchanger transfers collector heat
9. Flues, Vents & Combustion Air - 10-11% of exam; Category III appliances (≥8 inch vent
diameter for higher heat input); power venting for Category IV appliances (positive
pressure); louvers (prevent rain ingress while allowing airflow)
, Page 2 of 105
10. Codes, Safety & References - IMC 2006, IFGC 2006, ASME CSD-1-2006, Arizona Boiler
Rules; OSHA 1926 safety (PPE, confined space entry, trenching); references used to
create questions but NOT allowed in testing center
100 MCQ Questions with Rationales
1. What is the primary scope of work permitted under an Arizona C-74 Boilers, Steamfitting
and Process Piping license?
A) Installation of new electrical service panels only
B) Installation, alteration, and repair of steam and hot water systems, boilers, process piping,
and solar equipment
C) Plumbing installation for all building systems
D) Full electrical wiring for all building circuits
Correct Answer: B
Rationale: The C-74 license covers installation, alteration, and repair of steam and hot water
systems and boilers, including chimney connections, flues, refractories, burners, piping, fittings,
valves, thermal insulation, accessories, process piping, and solar equipment .
2. What electrical work is a C-74 licensee permitted to perform?
A) Installation of a new main service panel
B) Installation of a new sub-panel
C) Adding a new circuit to an existing service panel or sub-panel
D) Full electrical service upgrades
, Page 3 of 105
Correct Answer: C
Rationale: A C-74 licensee may add a new circuit to an existing service panel or sub-panel.
Installation of a new service panel or sub-panel is specifically excluded from scope .
3. How many questions are on the Arizona C-74 examination?
A) 50
B) 60
C) 80
D) 100
Correct Answer: C
Rationale: The C-74 exam consists of 80 questions .
4. What is the time limit for completing the Arizona C-74 exam?
A) 2 hours
B) 2.5 hours
C) 3 hours
D) 4 hours
Correct Answer: C
Rationale: The C-74 exam has a 3-hour time limit .
5. What is the passing score for the Arizona C-74 examination?
A) 65%
B) 70%
, Page 4 of 105
C) 75%
D) 80%
Correct Answer: B
Rationale: The C-74 exam requires a score of 70% correct to pass .
6. What percentage of the C-74 exam covers Steam/Hot Water Piping?
A) 10%
B) 15%
C) 19-20%
D) 25%
Correct Answer: C
Rationale: Steam/Hot Water Piping comprises 19-20% of the exam content, making it the largest
topic area .
7. What percentage of the C-74 exam covers Boilers?
A) 5%
B) 10%
C) 15%
D) 20%
Correct Answer: B
Rationale: The Boilers topic comprises 10% of the exam .
8. What percentage of the C-74 exam covers Solar?
