456A Red Seal — Welder

About the 456A Red Seal Exam — Welder

The 456A Welder Red Seal exam is Canada's national certification for welders who work across industrial, construction, pipeline, and manufacturing sectors. A Red Seal 456A endorsement validates your knowledge of all major welding processes, blueprint reading, metallurgy, and welding standards — and allows you to work anywhere in Canada without provincial re-examination.

The exam consists of 125 multiple-choice questions based on the 2023 Red Seal Occupational Standard (RSOS), with a passing score of 70%. Exam time is 4 hours.

Official 456A Exam Breakdown (red-seal.ca)

Red Seal publishes how the 125 questions on the real 456A exam are distributed across its Major Work Activities:

• A — Performs Common Occupational Skills — 20 questions (16%)
• B — Performs Layout and Fabrication of Components for Welding — 28 questions (22%)
• C — Performs Cutting and Gouging — 23 questions (18%)
• D — Welding Processes — 54 questions (43%)

Every question is four-option multiple choice with one correct answer, the writing time is four hours and the pass mark is 70%. Source: 456A exam information, red-seal.ca. Exams are periodically rewritten to updated occupational standards, so check that page before you book.

What this question bank covers

These are the topic areas in this practice bank and what each one covers. The real 456A exam has 125 questions and a four-hour writing time. How those questions are distributed across the official blocks is published by Red Seal — see the 456A exam information page.

• SMAW — Shielded Metal Arc Welding — Electrode classification (E7018, E6010, E6011), polarity selection (DCEP/DCEN), amperage settings per electrode diameter, striking an arc, weaving patterns, and identifying weld discontinuities. The most heavily tested process.
• GMAW — Gas Metal Arc Welding — Short-circuit, spray, and pulse transfer modes, wire feed speed vs. voltage relationships, shielding gas selection (C25, 100% Argon, C10), contact tip-to-work distance, and GMAW-P (pulsed GMAW) for thin materials.
• GTAW — Gas Tungsten Arc Welding — AC vs. DC polarity for aluminum vs. steel, tungsten electrode preparation and contamination, filler rod selection (ER70S-2, ER308L for stainless), back-purging requirements, and high-frequency start.
• FCAW — Flux-Cored Arc Welding — Self-shielded vs. gas-shielded FCAW, E71T-1 vs. E71T-8 electrode selection, porosity causes, out-of-position capabilities, and weld quality in structural applications.
• Welding Theory, Metallurgy & Distortion — Heat input calculations, pre-heat and interpass temperature requirements, hardenability and carbon equivalent (CE), HAZ characteristics, and distortion control techniques (backstep, balanced welding).
• Safety, Codes & Symbols — CSA W47.1, CSA W59, CWB certification categories, blueprint reading and weld symbols (AWS A2.4), PPE requirements, fire watch, confined space, and fume extraction.
• OFC — Oxyfuel Cutting — Tip selection, pressures, kerf width, and cutting speed for different steel thicknesses. Plasma arc cutting (PAC) basics also appear.

Exam Strategy for 456A

Theory, not technique. The Red Seal exam tests your understanding of WHY — why you choose a specific polarity, why porosity occurs, why pre-heat is required — not just your ability to weld. Strong candidates who may not be the best welder in the shop often outscore skilled welders who haven't studied the theory.

Master weld symbols. AWS A2.4 weld symbols appear on nearly every 456A exam. Practice interpreting groove welds, fillet welds, back/backing welds, and surfacing symbols from a print.

Know your discontinuities. The ability to identify discontinuity causes (porosity, undercut, incomplete fusion, hot cracks, cold cracks) and link them to process parameters is heavily tested.

How to Use This Practice Tool

This free tool provides 125 questions across all 456A topics with detailed answer explanations. Use Topic Filter to isolate SMAW and GMAW questions first — they account for nearly 40% of the exam. Use Mock Exam Mode to simulate timed testing conditions.

Related reading: How to Pass the 456A Red Seal Exam | Welder Salary Guide | Welder Career Guide Canada