Ontario Refrigeration Operator Class A Exam
(TSSA) QUESTIONS AND VERIFIED ANSWERS WITH
RATIONALES JUST RELEASED
Ontario Refrigeration Operator Class A Exam (TSSA) – Practice Questions
10 Most Tested Coverage Areas
1. Acts, Regulations, and Codes – TSSA Act, Operating Engineers Regulation (O. Reg. 219/01), CSA
B52 (Mechanical Refrigeration Code), CSA B51 (Boilers & Pressure Vessels), CEPA E2
Environmental Emergency Regulations, and Directors Orders .
2. Safety – Hazards associated with refrigeration plant operation (ammonia, CO2, halocarbons),
required precautions, PPE (respirators per CSA Z94.4), emergency procedures, and leak
detection .
3. Refrigerants, Processes, and Systems – Halocarbons (CFCs, HCFCs, HFCs, HFOs),
organic/inorganic compounds (ammonia, CO2), azeotropes, steam-jet, air-cycle, absorption, and
hermetic centrifugal machine design .
4. Industrial Systems and System Operation – Multi-stage and cascade refrigeration, purge
systems, oil stills, liquid receivers, coolers, and troubleshooting oil/moisture/water issues,
refrigerant content, and discharge temperatures .
5. Thermodynamics and Calculations – Vapour compression cycle, reversed Carnot Cycle,
Pressure-Enthalpy (P-h) chart interpretation, Coefficient of Performance (COP), refrigerating
effect, mass flow rate, piston displacement, theoretical power, and tonnes of refrigeration .
6. Psychrometrics and Air Conditioning – Building on Class B knowledge: psychrometric chart use,
air conditioning principles, and system types .
7. Centrifugal and Screw Compressors – Operation, maintenance, and management of centrifugal
chiller systems, screw compressors, and their auxiliaries .
8. Lubrication Principles – Lubrication requirements and problems for plants using anhydrous
ammonia, carbon dioxide, and Freon; oil systems; oil stills .
9. Compressor Operation and Auxiliaries – Pumps, compressors, basic electricity, auxiliaries, and
control systems .
10. Environmental Issues – Impact of refrigerants on the environment, regulations, and best
practices .
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Question 1
The Technical Standards and Safety Authority (TSSA) oversees the examination and certification of
Operating Engineers and Operators in Ontario to ensure they possess the necessary qualifications to
safely manage registered power plants. According to the TSSA Class "A" Certification and Examination
Guide, on which legal framework is this regulatory authority primarily based for refrigeration operators?
A) The Environmental Protection Act and O. Reg. 347
B) The Technical Standards & Safety Act, 2000 and O. Reg. 219/01
C) The Ontario Building Code and CSA B52
D) The Canada Labour Code and CSA Z94.4
Correct Answer: B
Rationale: The TSSA administers the certification of Operating Engineers and Operators based on the
Technical Standards & Safety Act, 2000 and the Operating Engineers Regulation (Ontario Regulation
219/01) .
Question 2
An operator is preparing for the Refrigeration Operator Class "A" examination and needs to understand
the regulatory framework governing their work. According to the TSSA Class "A" examination syllabus,
which of the following codes must a candidate be able to reference for information on the operation,
maintenance, inspection, and testing of a compressor plant?
A) CSA B52: Mechanical Refrigeration Code
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B) CSA B149: Natural Gas and Propane Installation Code
C) CSA C22.1: Canadian Electrical Code
D) CSA Z462: Workplace Electrical Safety Standard
Correct Answer: A
Rationale: The TSSA Class "A" syllabus specifically lists CSA B52: Mechanical Refrigeration Code as a key
reference for locating information about compressor plant staffing and operation .
Question 3
A refrigeration plant operator is evaluating the environmental regulations that apply to their facility.
According to the TSSA Class "A" Certification and Examination Guide, which federal regulation is listed as
a required knowledge area for applicants regarding environmental emergencies?
A) Fisheries Act and O. Reg. 419/05
B) Canadian Environmental Protection Act, 1999 (CEPA) – E2 Environmental Emergency Regulations
C) Transportation of Dangerous Goods Act and Regulations
D) Canadian Water Act and O. Reg. 387/04
Correct Answer: B
Rationale: The CEPA E2 Environmental Emergency Regulations are specifically listed in the Class "A"
syllabus as a key regulation that candidates must be able to reference .
Question 4
A candidate is reviewing the application requirements for TSSA Refrigeration Operator Class "A"
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certification and is calculating their qualifying experience. What is the practical operating training
requirement in hours for a candidate who has NOT completed a TSSA-approved time-reduction training
program?
A) 1,280 hours as a trainee in a Class A refrigeration plant
B) 1,760 hours as a trainee in a Class A refrigeration plant
C) 1,920 hours as a trainee in a Class A refrigeration plant
D) 2,400 hours as a trainee in a Class A refrigeration plant
Correct Answer: C
Rationale: The standard practical operating training requirement for Class "A" certification is 1,920
hours in a Class A refrigeration plant. This is reduced to 1,760 hours only for candidates who have
completed a full-time TSSA "approved-for-time-reduction" program .
Question 5
A candidate has completed a full-time TSSA-approved training program for Refrigeration Operator Class
"A" and is applying for their certificate. Which statement accurately reflects the practical operating time
requirement for this candidate?
A) The requirement is 1,920 hours as a trainee in a Class A plant
B) The requirement is 1,760 hours, which is a reduction from the standard 1,920 hours
C) The requirement is 1,440 hours, which is the same as for Compressor Operator
D) The requirement is waived entirely upon completion of the training program