Red Seal Sheet Metal Worker Interprovincial Exam
The Red Seal Sheet Metal Worker exam is the interprovincial certification exam for the trade Ontario registers as Sheet Metal Worker (308A). It has 120 multiple-choice questions drawn from five major work activities, from pattern development and fabrication to installing air and material handling systems, roofing and specialty products, and the Red Seal pass mark is 70%. You apply for and write it through your provincial or territorial apprenticeship authority.
- 120 questions
- 70% to pass
- 4 hours
Last checked against Red Seal Program (with provincial and territorial apprenticeship authorities) on .
Red Seal Sheet Metal Worker (308A) at a glance
- Number of questions
- 120 multiple-choice questions source ↗
- Pass mark
- 70% source ↗
- Maximum time allowed
- 4 hours source ↗
- Question format
- Multiple choice: one correct answer and three distractors source ↗
- Largest exam area
- MWA C, installs air and material handling systems: 41 of 120 questions source ↗
- Pattern development (task B-5)
- 13 of 120 questions; only tasks B-6 and C-11 (16 each) are larger source ↗
- National Occupational Classification
- NOC 72102 source ↗
- Ontario apprenticeship (308A)
- 9,000 hours: 8,280 on the job and 720 in school (three levels); compulsory trade in Ontario source ↗
Ready for the real Red Seal Sheet Metal Worker exam?
- ✓ 600 Red Seal Sheet Metal Worker practice questions, every answer explained and cited
- ✓ Full-length timed mock exams: 120 questions, 4 hours, scored against 70%
- ✓ Practise by topic and review every question you missed
- ✓ Every other Canadian exam on VoltExam included
What the Red Seal Sheet Metal Worker (308A) covers
| Area | Weight | What to know |
|---|---|---|
| A – Performs common occupational skills | 24 questions | Safety-related functions (5), using and maintaining tools and equipment (9), organizing work (7), and communication and mentoring techniques (3). |
| B – Performs fabrication | 38 questions | Pattern development (13), fabricating sheet metal components for air and material handling systems (16), fabricating flashing, roofing, sheeting and cladding (3), and fabricating specialty products (6). |
| C – Installs air and material handling systems | 41 questions | Preparing the installation site (7), chimneys, breeching and venting (6), air handling system components (16), material handling system components (5), insulation, lagging, cladding and flashing (3), and leak testing, air balancing and commissioning (4): the largest area on the exam. |
| D – Installs roofing and specialty products | 10 questions | Installing metal roofing and cladding/siding systems (3), exterior components (2) and specialty products (5). |
| E – Performs maintenance and repair | 7 questions | Performing scheduled maintenance (3) and repairing faulty systems and components (4). |
How to get certified
- 1
Register as an apprentice with your provincial or territorial authority
Apprenticeship is run by each province and territory. In Ontario the trade is Sheet Metal Worker (308A), administered by Skilled Trades Ontario. It is a compulsory trade there, so you must be registered (on the Public Register) to practise it legally.
- 2
Complete your on-the-job hours and technical training
Log your work-based hours with your employer and complete each level of in-school training. Ontario sets 8,280 hours on the job and 720 hours in school across three levels for 308A, about five years in total. Other jurisdictions set their own requirements.
- 3
Or apply as a trade qualifier / challenger
Experienced workers who never registered as apprentices can usually apply to challenge the exam by documenting their trade experience. Each authority sets its own hour thresholds and evidence rules, so check before you apply.
- 4
Get approved and write the exam
Once your authority confirms you are eligible, it tells you how and where to write. Expect 120 multiple-choice questions and up to 4 hours, with 70% needed to pass. Formulas you may need are provided at the exam.
- 5
Receive your certificate with the Red Seal endorsement
In Ontario, Skilled Trades Ontario issues the Certificate of Qualification when you pass. A pass on the interprovincial exam brings the Red Seal endorsement, which is recognized across participating provinces and territories.
How to study
- Study by the official weightings: fabrication (38 questions) and installing air and material handling systems (41 questions) together make up about two-thirds of the exam.
- Pattern development alone is 13 questions. Practise parallel line, radial line and triangulation layouts until you can pick the right method for any fitting at a glance.
- Drill the core calculations: stretchouts (π × D), cone slant heights and sector angles, true lengths, duct area and velocity, and the fan laws. The exam supplies formulas, but you need speed in applying them.
- Use the π key and only round your final answer, as Red Seal's exam page advises. Rounding mid-calculation is a common way to land on a distractor.
- Take timed practice sets: 120 questions in 4 hours is 2 minutes per question, so skip and return to long layout calculations rather than stalling.
Frequently asked questions
How many questions are on the Red Seal Sheet Metal Worker exam?
Red Seal lists 120 multiple-choice questions for this trade, split across five major work activities: 24 common occupational skills, 38 fabrication, 41 installing air and material handling systems, 10 installing roofing and specialty products, and 7 maintenance and repair.
How many correct answers do I need to pass?
The Red Seal pass mark is 70%. On a 120-question exam that means at least 84 correct answers, since 84 ÷ 120 is exactly 70%. Your provincial or territorial authority reports your result.
How long do I get to write it?
Red Seal states a maximum of 4 hours for its exams. Ask your apprenticeship authority about accommodations if you need them, because those are arranged locally.
Is 308A the same as the Red Seal Sheet Metal Worker trade?
Yes. Ontario's Sheet Metal Worker trade (308A) is part of the Interprovincial Red Seal Program. It is compulsory in Ontario, and the apprenticeship is 9,000 hours (8,280 on the job and 720 in school). Skilled Trades Ontario reports 279 Certificates of Qualification issued in the trade in 2025.
What kinds of questions are on the exam?
Red Seal says 20-30% of the questions test knowledge and recall, 60-70% test procedures and application, and 5-15% test critical thinking. Expect layout and calculation questions as well as installation and troubleshooting scenarios.
Is a formula sheet provided?
Yes. Red Seal says the formulas you may need are provided at the exam, and an acronym list is published for the trade. It advises using the π button and rounding only your final answer. You still need to know which formula to apply and how to apply it quickly.
Is pattern development a big part of the exam?
Yes. Task B-5, performs pattern development, accounts for 13 of the 120 questions, and more layout-based items appear under fabrication of duct components. Expect parallel line, radial line and triangulation methods, stretchouts and true lengths.
Which codes and standards should I study?
Sheet metal work draws on duct construction standards such as SMACNA's, NFPA 96 for commercial kitchen exhaust, the gas and oil installation codes (CSA B149.1 and CSA B139) for venting, and provincial building, fire and health and safety rules. Ask your authority or school which editions apply; our practice questions name standards for context only and do not quote them.
Are these practice questions from the real exam?
No. VoltExam's questions are original items written to practise the topics in the official exam breakdown. They are not official Red Seal questions, and doing well on them does not guarantee a pass.
Start practising for the Red Seal Sheet Metal Worker (308A) today
- ✓ 600 Red Seal Sheet Metal Worker practice questions, every answer explained and cited
- ✓ Full-length timed mock exams: 120 questions, 4 hours, scored against 70%
- ✓ Practise by topic and review every question you missed
- ✓ Every other Canadian exam on VoltExam included
Official sources
- Red Seal – Sheet Metal Worker trade page ↗
- Red Seal – Sheet Metal Worker exam information (breakdown) ↗
- Red Seal – Overview of the Red Seal Examination ↗
- Skilled Trades Ontario – Sheet Metal Worker ↗
- Skilled Trades Ontario – Sheet Metal Worker (308A) 2025 trade report ↗
Sources checked November 3, 2026. VoltExam is independent and not affiliated with Red Seal Program (with provincial and territorial apprenticeship authorities). Rules change: confirm details with the official source before your exam.