Gasfitter - Class A - Exam Information
Table of Contents
Self-Assessment
This tool can be used to reflect on your own experience and knowledge in the trade compared with what is on the exam.
Exam Breakdown
Each Red Seal exam's questions are developed to assess the activities laid out in the Red Seal Occupational Standard. This trade's Red Seal exam has 100 questions Footnote *, which are distributed as follows:
Major Work Activity A - Performs common occupational skills - 5 questions
Major Work Activity B – Installs fuel piping and tubing systems - 9 questions
Major Work Activity C – Installs venting and air supply systems - 13 questions
Major Work Activity D – Installs controls and electrical systems - 19 questions
Major Work Activity E - Installs and converts fuel systems, appliances and ancillary equipment - 13 questions
Major Work Activity F - Tests and commissions fuel systems, appliances and ancillary equipment - 23 questions
Major Work Activity G - Services fuel systems, appliances and ancillary equipment - 18 questions
Types of Exam Questions
All Red Seal exam questions are written in multiple-choice format. A multiple-choice question consists of question followed by four possible responses (A, B, C, D). Every question has exactly one correct answer and three incorrect options. They are not misleading or trick questions, but the incorrect options are not always obvious.
There are three types of questions that you will see on Red Seal Exams:
- Knowledge and Recall
- Procedural and Application
- Critical Thinking
Knowledge and Recall
This type of question tests your ability to recall and understand definitions, facts and principles.
For this trade, between 15 and 25% of questions that are this type.
Example of a Knowledge and Recall Question:
What is called the time it takes for a primary or programming control to shut off the fuel supply in the event of a loss of flame signal?
- Flame failure response time.
- Pilot relay shut-down.
- Turndown time.
- Flame lock-out.
Answer: A
Procedural and Application
This type of question tests your ability to apply your knowledge of procedures to a situation.
For this trade, between 60 and 70% of questions are this type.
Example of a Procedural and Application Question:
The positive air pressure switch on a DFMAH unit is being verified during an inspection. How is the pressure measurement obtained?
- By placing dual port manometer in parallel with pressure switch.
- By placing anemometer in series with pressure switch.
- By placing dual port manometer in series with pressure switch.
- By placing anemometer in parallel with pressure switch.
Answer: A
Critical Thinking
This type of question tests your ability to interpret data, solve problems and arrive at valid conclusions.
For this trade, between 10 and 20% of questions are this type.
Example of a Critical Thinking Question:
What is the minimum ventilation air opening for a boiler room containing a power burner with a firing rate of 1 000 000 Btuh?
- 3.34 in²
- 7.15 in²
- 10.00 in²
- 14.20 in²
Answer: C
Try more sample questions for this trade and check out the Exam Preparation Guide. It will give you practical insights on what goes into Red Seal exams, and how you can best prepare yourself to do well.
Math Formulas
The following formulas used in this trade may be needed to answer some questions on its Red Seal exam. They will also be provided with the exam sitting.
Formulas
Measurement unit abbreviations
- °C
- degree Celsius
- °F
- degree Fahrenheit
- °K
- degree Kelvin
- A
- ampere
- BHP
- boiler horsepower
- BTU
- British thermal unit
- Btuh
- British thermal units per hour
- CFH
- cubic feet per hour
- CFM
- cubic feet per minute
- ft.
- foot
- ft2
- square foot
- ft3
- cubic foot
- gal.
- imperial gallon
- gpm
- imperial gallons per minute
- hr
- hour
- in.
- inch
- in2
- square inch
- in3
- cubic inch
- kg
- kilogram
- kPa
- kilopascal
- kPaG
- kilopascal gauge
- kW
- kilowatt
- L
- litre
- lb.
- pound
- lbf
- pound - force
- m
- metre
- m2
- square metre
- m3
- cubic metre
- min
- minute
- mm
- millimetre
- psi
- pounds per square inch
- psia
- pounds per square inch absolute
- psig
- pounds per square inch gauge
- s
- second
- SCFM
- standard cubic feet per minute
- SPR
- seconds per rotation
- t
- ton (ice melted over a 24-hour period)
- USG
- American gallon
- USGPM
- American gallons per minute
- V
- volt
- VA
- volt-ampere
- W
- watt
Values
- ∆T
- temperature difference
- B
- base
- BarG
- bar gauge
- C
- specific heat of fluid
- CO2
- carbon dioxide
- D
- distance
- FCS
- fully closed signal
- FOS
- fully open signal
- H
- height
- HV
- heating value
- I
- current (in amperes)
- IS
- input signal
- L
- length
- M
- mass of fluid per hour
- P
- pressure
- Pbase
- base/atmospheric pressure
- Ptest
- test pressure
- PF
- pressure factor
- r
- radius
- R
- resistance (in ohms)
- SF
- safety factor
- stoich
- stoichiometric
- T
- temperature
- Tamb
- ambient temperature
- W
- width
Constants
- π
- 3.1416
- 1 ft3 of water
- 6.228 gal.
- 1 USG
- 8.33 lb.
- 45° offset
- 1.414
- 12 000 BTU (cooling capacity)
- 1 t
- Air- fuel ratio
- 14.7
- Base/atmospheric pressure
- 14.73 psig/psia
- Boiler horsepower (BHP)
- 33 500
- BTU per 1 000 W (single phase)
- 3.414
- BTU per 1 000 W (three phase)
- 1.73
- Heat content - natural gas
- 1 000 BTU/ft3
- Heat content - propane
- 2 500 BTU/ft3
- Pressure head conversion unit
- 0.433 psi/ft.
- Specific heat of air
- 1.08
- Standard for air at sea level
- 4.5
Conversion factors
| To convert | To | Multiply by |
|---|---|---|
| °C | °F | 1.8 and add 32 |
| °C | °K | 1 and add 273 |
| decimal | second | 60 |
| ft2 | in2 | 144 |
| ft3 | USG | 7.48 |
| kg | lb. | 2.205 |
| kPa | lbf/ft2 | 20.88 |
| kPa | lbf/in2 (psi) | 0.1450 |
| kPaG | lbf/in2 gauge (psig) | 0.1450 |
| L | USG | 0.2200 |
| L/min | USGPM | 0.2641 |
| L/s | gpm | 13.20 |
| m | ft. | 3.281 |
| m2 | ft2 | 10.76 |
| m3 | ft3 | 35.31 |
| mm | in. | 0.03937 |
General formulas
| Descriptions | Full | Abbreviated |
|---|---|---|
| % of CO2 | ||
| Actuator position (%) | ||
| Btuh | mass of fluid per hour × specific heat of fluid × temperature difference | |
| CFH | ||
| CFH | ||
| CFH | (dial size ÷ seconds per rotation) × seconds in 1 hour × pressure factor | |
| CFH | ||
| CFM | ||
| CO2 volume (combustion) | appliance output in Btuh × cubic feet of CO2 per cubic foot of gas ÷ heating value | |
| Fuse rating | amperes × safety factor | |
| Gauge pressure reading | ||
| Input (Btuh) | ||
| Input (Btuh) | (base pressure + dial size) × cubic feet per hour ÷ base pressure × heating value | |
| Input (Btuh) | cubic feet per hour × heating value | |
| Input (Btuh) | ||
| Net stack temperature | downstream flue temperature − ambient temperature | |
| Output (Btuh) | temperature difference × 1 USG × minutes in 1 hour × American gallons per minute | |
| Output (Btuh) | total number of boiler horsepower × number of boilers | |
| Power | volt × ampere | |
| Pressure factor | (base pressure + bar gauge) ÷ base pressure | |
| Pressure test | ||
| Purge time | cubic feet per minute × number of air changes ÷ exhaust fan capacity measured in standard cubic feet per minute | |
| Seconds per rotation | ||
| Travel | offset distance × 45° offset constant | |
| Volt ‑ ampere | current × voltage | |
| Voltage | current × resistance |
Area formulas
| Description | Full | Abbreviated |
|---|---|---|
| Circle | π × radius squared | |
| Rectangle | length × width | |
| Sphere | 4 × π × radius squared | |
| Triangle |
Volume formulas
| Description | Full | Abbreviated |
|---|---|---|
| Cuboid | length × width × height | |
| Cylinder | π × radius squared × height | |
| Sphere |
Acronyms
The following acronyms used in this trade may be on its Red Seal exam. They will also be provided with the exam sitting.
- ABS
- acrylonitrile butadiene styrene
- AHJ
- authority having jurisdiction
- ACR
- air conditioning and refrigeration
- ANSI
- American National Standards Institute
- BFS
- block flue switch
- BHP
- boiler horsepower
- CAPS
- combustion air proving switch
- CEC
- Canadian Electrical Code
- cfm
- cubic feet/minute
- CPVC
- chlorinated polyvinyl chloride
- CSA
- Canadian Standards Association
- DFMAH
- direct-fired make-up air heater
- DWV
- drain, waste, vent
- FARC
- fuel/air ratio control
- FLA
- full load amps
- HGPS
- high gas pressure switch
- HWA
- high water alarm
- I.D.
- inside diameter
- IR
- infrared
- LGPS
- low gas pressure switch
- L/HGPS
- low/high gas pressure switch
- LP
- liquid propane
- LWCO
- low water cut-off
- NBC
- national building code
- NPS
- nominal pipe size
- O.D.
- outside diameter
- OHS
- Occupational Health and Safety
- OSHA
- Occupational Safety and Health Administration
- PID
- proportional integral derivative
- POC
- proof of closure
- PPE
- personal protective equipment
- ppm
- part per million
- psi
- pounds per square inch
- psia
- pounds per square inch absolute
- psig
- pounds per square inch gauge
- PTFI
- pilot trial for the ignition
- QNFT
- quantitative fit test
- rpm
- rotations per minute
- RTV
- room temperature vulcanizing (silicone)
- scfm
- standard cubic feet/minute
- spr
- seconds per revolution
- SSOV
- safety shut-off valve
- USWG
- U.S. water gallon
- UV
- ultraviolet
- VAC
- Volts/Alternative Current
- VDC
- Volts/Direct Current
- VFD
- variable frequency drive
- VPS
- valve proving system
- w.c.
- water column
- WHMIS
- Workplace Hazardous Materials Information System
For more information about exam preparation materials contact your provincial/territorial apprenticeship office.