TssaGasTech Practice Test
Free · 150 Questions.

Question 1

Under Ontario Regulation 212/01 (Gaseous Fuels), what is the maximum appliance input a Gas Technician 2 (G2) may work on without direct supervision?

• A. Unlimited input on residential and industrial equipment
• B. Up to and including 400,000 BTU/h (120 kW)
• C. Up to and including 250,000 BTU/h (75 kW)
• D. Up to and including 1,000,000 BTU/h (300 kW)

Explanation: A Gas Technician 2 (G2) certificate holder is authorized to install, inspect, alter, purge, activate, repair, and service any gas appliance with an input of 400,000 BTU/h or less.

Question 2

What type of pipe threads are required on steel natural gas piping under CSA B149.1?

• A. National Pipe Taper (NPT) standard threads
• B. Standard British Parallel Pipe (BSPP) straight threads
• C. Unified National Fine (UNF) machine threads
• D. Acme square trapezoidal heavy-duty threads

Explanation: CSA B149.1 mandates National Pipe Taper (NPT) threads for threaded steel gas pipe, ensuring a tapered interference seal when joined with approved pipe thread sealant.

Question 3

Which venting category designates a gas appliance that operates with a non-positive vent pressure and a flue gas temperature high enough to avoid condensation?

• A. Category IV appliance (positive vent pressure, condensing flue gas)
• B. Category I appliance (e.g., standard natural draft or fan-assisted furnace)
• C. Category II appliance (non-positive vent with condensing flue gas)
• D. Category III appliance (positive vent pressure, non-condensing flue gas)

Explanation: Category I appliances operate with negative/non-positive vent pressure and non-condensing flue gases (e.g., standard atmospheric draft or fan-assisted B-vent appliances).

Question 4

How much direct-current (DC) voltage does a properly heated standard thermocouple generate?

• A. 500 to 750 millivolts DC (loaded: 250 to 350 mV)
• B. 20 to 30 millivolts DC (loaded: 10 to 15 mV)
• C. 1.5 to 3.0 volts direct current (DC)
• D. 12 to 24 volts alternating current (AC)

Explanation: A standard thermocouple consists of two dissimilar metals and produces an open-circuit voltage of approximately 20 to 30 mV DC when heated by the pilot flame.