Gasfitter Class A Red Seal — Gas Fitter (Class A)

About the Red Seal Gasfitter — Class A Exam

Where this applies: Gasfitter — Class A is a Red Seal trade examined through provinces such as BC, Alberta, Saskatchewan and Manitoba. In Ontario, gas work is licensed by TSSA as Gas Technician G3/G2/G1 — it is not an Ontario apprenticeship trade and the Red Seal gasfitter endorsement is not recognized there. This question bank covers the Red Seal (CSA B149.1-based) scope, which overlaps heavily with TSSA G2/G1 material.

The Red Seal Gasfitter (Class A) exam is the interprovincial certification for gas fitters working on all types and pressures of natural gas and propane systems. Class A certification covers residential, commercial, and industrial gas installations including high-pressure supply, appliance commissioning, venting design, and combustion analysis.

The exam consists of approximately 100 multiple-choice questions based on the 2023 Red Seal Occupational Standard (RSOS) and aligned with CSA B149.1 Natural Gas and Propane Installation Code, with a passing score of 70%. Exam time is 3 hours.

Topic Breakdown (2023 RSOS)

• Appliances & Combustion Equipment (~22%) — Furnaces, boilers, water heaters, unit heaters, infrared heaters. Burner adjustment, heat exchanger inspection, ignition systems, and commissioning.
• Gas Supply Systems (~18%) — Meter sets, regulators (service, line, appliance), pressure testing, odourant, and first/second stage regulation.
• Piping Systems (~16%) — Pipe sizing using pressure drop tables, pipe materials (black steel, CSST, copper, PE), fittings, supports, and leak detection.
• Venting Systems (~16%) — Category I–IV venting, natural/induced/direct vent, common vent sizing, termination clearances.
• Combustion Theory & Air (~14%) — Stoichiometric combustion, excess air, CO/CO₂ analysis, combustion air requirements (0.08 m²/kW).
• Safety, Codes & Regulations (~14%) — CSA B149.1, provincial requirements, permits, pressure testing, gas leak response, purging.

Official Gasfitter Class A Exam Breakdown (red-seal.ca)

The official Red Seal exam information for Gasfitter — Class A lists 100 questions divided across seven blocks of Major Work Activities:

• A — Common occupational skills — 6 questions (6%)
• B — Piping preparation & assembly — 10 questions (10%)
• C — Venting & air supply — 11 questions (11%)
• D — Controls & electrical — 20 questions (20%)
• E — System & equipment installation — 20 questions (20%)
• F — Testing & commissioning — 15 questions (15%)
• G — Gas appliance service — 18 questions (18%)

Every question is four-option multiple choice with exactly one correct answer, and the pass mark is 70%. Expect an applied exam: roughly 50–60% of questions are procedural and application style and another 25–35% are critical thinking, with only 10–20% straight knowledge and recall. Controls, installation, commissioning and appliance service together account for almost three-quarters of the paper, so hands-on installation and service judgement matters more than memorized definitions.

How Our 100-Question Bank Maps to It

Our free bank also contains 100 questions, organized by the topic filters above the quiz. Piping questions support Block B; Venting and Combustion questions cover Block C and the combustion-air side of installation work; Appliances questions train the equipment knowledge behind Blocks E and G; and Gas Supply plus Safety & Code questions build the CSA B149.1 code judgement you need across every block. Drill one topic at a time, then run the Mock Exam for a mixed, exam-style simulation. For strategy, read How to Pass the Gasfitter Class A Exam and Common Gasfitter Class A Exam Mistakes; for the bigger picture, see the Gas Fitter Career Guide.

How to Use This Practice Tool

This free tool includes 100 questions covering all Gasfitter Class A topic blocks with full explanations citing the relevant CSA B149.1 section for every answer. Use Topic Filter to drill your weakest areas. Run the Mock Exam to simulate the real 100-question timed format.

Related reading: How to Pass the Gasfitter Class A Red Seal Exam | Gas Fitter Salary Guide | Gas Fitter Career Guide Canada