Everything you need to know about the Red Seal exam structure — question counts, time limits, how computer-based testing works, and how scoring and retakes are handled.
The Red Seal exam is a multiple-choice certification test administered at authorized testing centres across Canada. You can't bring your own notes or reference books; any reference material the exam allows is provided. Whether you're writing the 421A Heavy Duty Equipment Technician exam or the 309A Construction Electrician exam, the format follows the same structure — but the question count and topic weighting differ by trade, and Red Seal's Exam Preparation Guide gives the writing time as four hours.
This guide covers everything: how many questions each trade has, how long you have to complete them, what the pass mark is, how the computer-based testing works, and what happens if you don't pass.
| Trade | Questions | Time Limit | Pass Mark | Min. Correct |
|---|---|---|---|---|
| 421A — Heavy Duty Equipment Technician | 135 | 4 hours | 70% | 95 / 135 |
| 310T — Truck & Transport Mechanic | 135 | 4 hours | 70% | 95 / 135 |
| 310S — Automotive Service Technician | 125 | 4 hours | 70% | 88 / 125 |
| 306A — Plumber | 125 | 4 hours | 70% | 88 / 125 |
| 313A — Refrigeration & AC Mechanic | 125 | 4 hours | 70% | 88 / 125 |
| 456A — Welder | 125 | 4 hours | 70% | 88 / 125 |
| 308A — Sheet Metal Worker | 120 | 4 hours | 70% | 84 / 120 |
| 420B — Ironworker (Generalist) | 120 | 4 hours | 70% | 84 / 120 |
| 309A — Construction Electrician | 100 | 4 hours | 70% | 70 / 100 |
| 442A — Industrial Electrician | 100 | 4 hours | 70% | 70 / 100 |
| Gasfitter Class A | 100 | 4 hours | 70% | 70 / 100 |
Min. Correct is the fewest correct answers that reach 70%; SkilledTradesBC rounds results up from 69.5%, so 94 correct on a 135-question exam and 87 on a 125-question exam also pass there.
At approximately 1.8–2.4 minutes per question, practise your pace as well as the material. Spending more than 3 minutes on any single question is a sign you should flag it, move on, and return.
Printable question banks, by trade. Each is a PDF of that trade's full practice bank with the answer key and explanations, plus revision notes as a second file. The same questions are free on the quiz pages linked in the table.
All Red Seal exam questions are four-option multiple choice. Each question presents one correct answer and three plausible distractors. Red Seal's Exam Preparation Guide says textbooks can be helpful study resources, but they are not the basis of the exam; the occupational standard is.
All questions are 4-option MCQ. No essays and no diagrams to draw, but some questions involve calculations — Red Seal's Exam Preparation Guide lists a calculator among the supplies provided if one is needed.
No notes or textbooks of your own. For code-based trades the code book may be supplied at the exam, so confirm with your province. For example, SkilledTradesBC provides the 2024 Canadian Electrical Code for 309A Construction Electrician (checked October 2026).
Delivered at authorized testing centres. You can flag questions and return to them before submitting.
Wrong answers don't subtract points. Always answer every question — never leave one blank.
The Red Seal exam is divided into topic blocks based on the Red Seal Occupational Standard (RSOS). Red Seal publishes the exact number of questions in each block on every trade’s exam information page. Knowing the weighting tells you where to focus your study time.
421A Heavy Duty Equipment Technician official distribution (135 questions):
Source: red-seal.ca exam information.
310T Truck & Transport Mechanic official distribution (135 questions):
Source: red-seal.ca exam information.
For the 309A, 310S, and 313A, refer to the full topic breakdown on their respective trade pages and our Red Seal Study Guide.
Red Seal's Exam Preparation Guide describes an exam booklet and a bubble sheet for recording answers. Delivery is set by your province or territory, so confirm the format with your apprenticeship authority. If your exam is computer-based, expect roughly the following:
Failing the Red Seal exam is not the end of the road. Red Seal does not publish pass rates, so treat any figure you see quoted with caution. If you don't pass:
Knowing the format changes how you should study:
Our free practice questions and Mock Exam mode mirror the real Red Seal format — 4-option MCQ, questions from every topic, and timed results. Choose your trade:
The number of questions is set per trade and published by Red Seal. Among the trades covered here: 421A Heavy Duty Equipment Technician and 310T Truck & Transport Mechanic have 135 questions; 306A Plumber, 310S Automotive Service Technician, 313A Refrigeration & AC Mechanic and 456A Welder have 125; 308A Sheet Metal Worker and 420B Ironworker (Generalist) have 120; 309A Construction Electrician, 442A Industrial Electrician and Gasfitter Class A have 100. Check your own trade's exam information page at red-seal.ca, since exams are being rewritten to updated occupational standards.
Red Seal's Exam Preparation Guide gives the writing time as four hours and suggests dividing 240 minutes by your trade's number of questions: about 1.8 minutes per question on a 135-question exam and 2.4 minutes on a 100-question exam.
Red Seal's Exam Preparation Guide sets the pass mark at 70%, with each question worth one mark. That is 95 correct answers on a 135-question exam (421A, 310T), 88 on 125 (306A, 310S, 313A, 456A), 84 on 120 (308A, 420B) and 70 on 100 (309A, 442A, Gasfitter Class A); SkilledTradesBC rounds results up from 69.5%, so 94 correct on a 135-question exam and 87 on a 125-question exam also pass there.
You cannot bring your own notes, reference books, or textbooks into the exam room, but it is not strictly closed-book: any reference material the exam allows is provided. Red Seal's Exam Preparation Guide lists an acronym list, math formulas, and code book information, if required, among the supplies given to you. Where a trade's exam uses a code book, your authority may supply it: SkilledTradesBC, for example, provides the 2024 Canadian Electrical Code for 309A Construction Electrician (checked October 2026). Check with your apprenticeship authority before your exam date.
Rewrite rules are set by each province or territory. Skilled Trades Ontario and SkilledTradesBC both require a 30-day wait after a failed attempt. Further attempts can carry conditions: SkilledTradesBC requires apprentices to submit an approved study plan before a third attempt, and Alberta requires journeypersons and qualification-certificate holders who apply to write the Red Seal exam after two or more attempts to show at least 40 hours of additional study or upgrading. SkilledTradesBC's results letter gives your mark on each topic area, so you can focus your study on the weakest ones.
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