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Consistent daily practice beats last-minute cramming. Red Seal Pass uses the Ebbinghaus spaced-repetition method to schedule automated review of your wrong answers at 1, 3, and 7-day intervals, paired with real-time AI Journeyperson explanations.

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308A Sheet Metal Worker Red Seal Practice Test: Free Quiz

Q: Can I sample practice questions before subscribing?

Yes. You can take the interactive 10-question readiness quiz directly on this page with no sign-up required, or download our free 30-question printable sample mock exam PDF with step-by-step answer explanations. A subscription unlocks all 1200 Sheet Metal Worker (308A) questions, spaced-repetition review, and AI tutoring.

Preparing for the Red Seal Sheet Metal Worker (308A) exam

The Red Seal (Interprovincial) Sheet Metal Worker (308A) exam tests everything a working worker needs: pattern development and layout, triangulation, SMACNA duct fabrication, HVAC installation, and welding. Trying to memorize a thousand questions the night before rarely sticks. Research on the Ebbinghaus forgetting curve shows that spaced review holds knowledge better than cramming.

Red Seal Pass gives you a smarter path: a focused set of new questions each day, automatic review of the ones you miss, and clear explanations so you learn why, not just what.

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📥 Free Printable 30-Question Sheet Metal Worker (308A) Mock Exam PDF

Download our 30-question sample mock exam PDF with complete step-by-step answer keys and a blueprint breakdown.

🎧 Listen: the 30 Sheet Metal Worker (308A) Questions, Read Aloud

The same 30 questions as the free PDF, each read aloud with a 5-second pause before the answer and explanation.

Red Seal Sheet Metal Worker (308A) 30 practice questions video

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Official Sheet Metal Worker (308A) exam blueprint

Published by red-seal.ca for the 120-question Interprovincial exam. These weightings decide how many questions you face in each area, so they decide where your study time belongs.

Major Work Activity	Questions	Share
MWA A: Performs common occupational skills	24	20.0%
MWA B: Performs fabrication	38	31.7%
MWA C: Installs air and material handling systems	41	34.2%
MWA D: Installs roofing and specialty products	10	8.3%
MWA E: Performs maintenance and repair	7	5.8%
Total	120	100%

Exam time 4 hours · pass mark 70%. Source: red-seal.ca official exam breakdown.

10-Question Sheet Metal Worker (308A) Quick Readiness Quiz — with Full Worked Answers

No sign-up and no email required. Take this 5-minute diagnostic quiz to test your current exam readiness. Every answer below includes complete code citations and worked steps — the same standard as the other 1190 questions in the full bank.

⚡ Interactive Readiness Quiz

Click any option (A–D) below to test yourself & reveal the worked explanation.

Question 1 of 10

A sheet metal worker in Calgary is hanging supply duct 3.5 m above a concrete floor along an open mezzanine edge. There are no guardrails, an aerial lift cannot reach the area, and a travel restraint line would stop the worker short of the edge where the duct must be joined. Which fall protection method does the worker need?

A) A travel restraint system set so that the worker stops just short of the edge

B) A fall arrest system: full-body harness, energy-absorbing lanyard and anchor

C) A safety monitor watching the worker, with warning lines set along the edge

D) A safety net hung below the work area, so no harness is needed on the worker

Correct answer: B

Fall protection is required at about 3 m in most provinces. Guardrails come first, then travel restraint; where the worker must reach the open edge and restraint cannot be used, a personal fall arrest system with a full-body harness, energy-absorbing lanyard and suitable anchor is required. A monitor and warning lines do not protect a worker at this height.

Question 2 of 10

A welder on a Fort McMurray job is to weld structural brackets for a heavy duct support, and the procedure calls for low-hydrogen electrodes. A can of them was left open on the bench overnight in damp weather, and a rod oven holding the same type is in the site shop. What should the welder use?

A) Rods from the oven, as damp low-hydrogen rods can cause cracking in the weld

B) Rods from the open can, as the flux coating dries out once the arc is struck

C) Rods from the open can, after each one has been wiped with a clean dry rag

D) Rods from either source, as the moisture affects only the look of the weld

Correct answer: A

Low-hydrogen coatings pick up moisture, and that moisture brings hydrogen into the weld, which can cause cracking. Rods from the oven have been kept dry. The arc does not dry the coating in time, and wiping the surface does nothing for moisture already in the flux.

Question 3 of 10

A journeyperson in a Burnaby shop must cut a 60 mm round hole in the middle of a 26-gauge galvanized panel for a sensor port, after drilling a starting hole. The curve is too tight for the regular aviation snips to follow cleanly. Which hand snips are made for cutting tight circles like this?

A) Duckbill tinner's snips, whose wide blades leave a smoother edge on curves

B) Bulldog snips, whose short heavy blades are made for thicker straight cuts

C) Straight-cut aviation snips, which follow any curve if the cut is slow

D) Hawk-bill snips, whose narrow curved blades can turn inside a tight radius

Correct answer: D

Hawk-bill, or circle, snips have narrow curved blades that can cut tight circles and holes in thin sheet. Bulldog snips are for heavier straight cuts, and straight snips and wide-bladed snips cannot turn a small radius.

Question 4 of 10

A crew in a Hamilton shop is lining a 48 in. wide supply duct that will run at a fairly high velocity. An apprentice has been laying the liner on adhesive only, as it seems to hold well on the bench. The specification follows the SMACNA liner standard. How should this liner be fastened to the duct?

A) With adhesive only, since a full coat holds the liner at any velocity in use

B) With mechanical fasteners only, since adhesive adds nothing to the fastening

C) With adhesive and also mechanical fasteners, such as weld pins with washers

D) With foil tape only, since tape along the joints holds the sheets in position

Correct answer: C

The SMACNA liner standard calls for adhesive coverage together with mechanical fasteners, since adhesive alone can let go over time and at velocity, and fallen liner can block the duct. Fasteners alone leave the sheet free to lift between pins, and tape along the joints does not hold the sheet to the wall.

Question 5 of 10

A worker in a Kingston shop is developing a conical transition, 24 in. high, 36 in. across at the base and 12 in. at the top, to be closed with a grooved seam. What is the slant height of the side between the two ends, before any seam allowance is added?

A) 30.00 in., from the 24 in. height and an 18 in. change in radius

B) 24.00 in., the same as the vertical height of the transition

C) 25.46 in., from the 24 in. height and a 6 in. change in radius

D) 26.83 in., from the 24 in. height and the 12 in. change in radius

Correct answer: D

The slant height is the hypotenuse of the height and the difference in radii: 18 - 6 = 12 in. Square root of (24 squared + 12 squared) = square root of 720 = 26.83 in. Seam allowances go on the pattern edges, not on the slant height.

Question 6 of 10

A shop in Hamilton is bending 10 ft long flanges on a large hydraulic press brake. The bends come out at 90 degrees near both ends but only about 87 degrees in the middle, so the flanges look like a shallow canoe. What is the brake's crowning system for?

A) It feeds lubricating oil along the V-die during every stroke, so the sheet slides evenly into the die

B) It offsets the bed and ram flexing under load, so the punch goes equally deep along the whole length

C) It trims the ends of the flange as it bends, so the finished length matches the drawing exactly

D) It heats the middle of the tooling, so that the centre of the bend has no springback at all

Correct answer: B

Under heavy tonnage the ram and bed deflect, so the punch goes deeper at the ends than in the middle, leaving the middle under-bent. Crowning bows the bed slightly to match, giving the same penetration and angle along the full length.

Question 7 of 10

A crew in a Halifax office is building trapeze hangers from strut channel and threaded rod for a wide rectangular duct. The apprentice has set the rods well out from the duct sides to leave room to work. The duct is 60 in. wide and fairly heavy. Where should the rods be placed?

A) Screwed into the middle of the duct bottom, with no channel below

B) At least 600 mm out from each side, so workers can walk on the bar

C) Close to the duct sides, so the channel carries the least bending

D) Spread in a V shape from one anchor, wider than the duct at the base

Correct answer: C

The trapeze channel acts as a beam between the two rods. Keeping the rods close to the duct sides keeps the span and bending short, so a lighter channel carries the load with little sag.

Question 8 of 10

A crew in a Timmins mill is connecting a chute to the inlet of a bucket elevator boot. The opening is 25 mm out of line, and the apprentice has forced the connection, which is pulling on the boot's casing. Dust is escaping at a gap on one side. What should the crew do?

A) Fit a proper transition or adjust the supports so that it lines up, then gasket and bolt the connection

B) Force the connection into line with a come-along, and leave the boot's casing pulled as it now sits

C) Leave the 25 mm gap on one side, as the dust will settle back into the elevator boot by itself

D) Fill the 25 mm gap with spray foam from a can, and leave the chute to rest on the foam at that point

Correct answer: A

A misaligned connection is corrected with the supports or a proper transition, then gasketed and bolted, so that nothing strains the casing and the joint is dust-tight. Forcing it puts load on equipment that is not designed for it. Foam neither seals nor supports in this service.

Question 9 of 10

A crew in a Red Deer house is assembling a listed solid-fuel chimney through two floors. The apprentice is stacking the sections with some arrows on the outer wall pointing up and others pointing down, since the sections seem to lock together either way. How should the sections be assembled?

A) With the sections oriented in any direction, and each locked as far as it will go by hand

B) With the sections alternating up and down, so that the joints hold together more tightly

C) With every section oriented as the maker's arrow shows, and each one fully locked

D) With the sections oriented in any direction, and a screw put through each joint to lock it

Correct answer: C

The maker's arrow sets the direction of each section, so that condensate and creosote stay inside the flue, and each joint is fully locked. Reversed sections can leak at the joints, and a section that seems to lock the wrong way is still in the wrong direction. A screw does not correct that.

Question 10 of 10

A crew in an Edmonton warehouse is fastening exposed-fastener metal wall panels to girts. The panel maker requires at least three fasteners per girt per panel, with no more than 300 mm between fasteners. The panels are 900 mm wide. Which fastener layout across each girt meets these rules?

A) Four fasteners spaced about 180 mm apart, all in the middle part of the panel and well away from the edges

B) Two fasteners, one near each edge of the panel, since the side lap of the next panel gives the third fastener point

C) Two fasteners, one at the side lap and one at the far edge, leaving the middle of the panel free to move

D) Three fasteners, about 225 mm in from each edge and one at the centre, so no gap between them exceeds 300 mm

Correct answer: D

Fasteners 225 mm in from each edge with one at the centre (450 mm) are 225 mm apart, meeting both the three-fastener minimum and the 300 mm maximum. Two per girt fails the minimum count.

308A Sheet Metal Worker Pattern Layout, SMACNA Duct & Airflow Reference

Essential formulas, Canadian code standards, and critical numerical thresholds tested on the Interprovincial Red Seal Sheet Metal Worker (308A) exam:

Sheet Metal / HVAC Topic	Formula or SMACNA Standard	Exam Application & Key Value
Bend Allowance & Setback	BA = (π ÷ 180) × Angle × (Inside Radius + K × Thickness)	Neutral axis shifts inward (K ≈ 0.33–0.44); stretchout uses neutral-axis diameter
Pattern Development Methods	Parallel Line (cylinders/tees), Radial Line (cones), Triangulation (transitions)	True Length (TL) = √(Plan Length² + Vertical Height²)
Duct Continuity & Airflow Equation	Q (CFM) = Area (ft²) × Velocity (FPM)	At 1,200 FPM in a 24 in. × 12 in. (2 ft²) duct, airflow Q = 2,400 CFM
Total, Static & Velocity Pressure	Total Pressure (TP) = Static Pressure (SP) + Velocity Pressure (VP)	Velocity V (FPM) = 4,005 × √(VP in. w.g.); Pitot tube measures TP and SP
Sensible Heat Transfer Formula	Q_s (BTU/hr) = 1.08 × CFM × ΔT (°F)	Used to calculate supply airflow or furnace/coil temperature rise
SMACNA Pittsburgh & Seam Allowances	Small Pittsburgh: ~1/4 in. flange + 3/4–1 in. pocket	Always add seam and lock allowances AFTER laying out net stretchout dimensions

Worked examples: duct airflow, stretchout and elbow mitre angles on the 308A exam

Two blocks make up nearly two-thirds of the 120-question exam: Installs air and material handling systems (41 of 120 questions) and Performs fabrication (38 of 120 questions). Continuity of airflow, cylinder stretchout and gore mitre angles are foundational calculations:

Worked example 1

A rectangular supply trunk measures 600 mm × 400 mm and carries air at a velocity of 7.5 m/s. What is the volumetric airflow rate in m³/s?

Convert duct dimensions to metres: area A = 0.60 m × 0.40 m = 0.24 m². Airflow Q = A × V = 0.24 m² × 7.5 m/s = 1.80 m³/s.

Answer: 1.80 m³/s (1,800 L/s).

Worked example 2

You are rolling a 250 mm diameter round pipe with a grooved seam requiring a total seam allowance of 24 mm. What is the flat stretchout width?

Circumference = π × D = 3.1416 × 250 = 785.4 mm. Add the seam allowance: 785.4 + 24 = 809.4 mm.

Answer: 809.4 mm.

Worked example 3

What is the mitre angle for laying out a 90° round elbow fabricated from 4 pieces?

Each end gore has 1 mitre factor and each middle gore has 2: mitre number = (2 × number of pieces) − 2 = (2 × 4) − 2 = 6. Mitre angle = 90° ÷ 6 = 15°.

Answer: 15° mitre line.

Duct gauge thickness, reinforcement spacing and hanger sizing must follow SMACNA Duct Construction Standards and the National Building Code.

A 4-week study plan for the Sheet Metal Worker (308A) exam

18 new questions a day is the pace the platform sets, because spacing beats cramming. Over four weeks that is about 504 questions, and the order below follows the official weightings above.

Week 1 — the heaviest area. MWA C: Installs air and material handling systems, which alone is 34.2% of the exam.
Week 2 — the next two. MWA B: Performs fabrication (31.7%) and MWA A: Performs common occupational skills (20.0%).
Week 3 — the remaining activities, plus every question you got wrong. Wrong answers return automatically on day 1, 3 and 7.
Week 4 — full-length timed runs. 120 questions in 4 hours, then review every mistake by Major Work Activity.

Booking the Sheet Metal Worker (308A) exam where you live

Eligibility and booking are handled by your province, not by the Red Seal program itself. Start here:

The full question bank

1200 Sheet Metal Worker (308A) questions, every one explained

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Frequently asked questions

How many questions are on the Red Seal Sheet Metal Worker (308A) exam?

The Interprovincial Red Seal Sheet Metal Worker (308A) exam has 120 multiple-choice questions, a 4-hour limit and a 70% pass mark, per the official exam breakdown on red-seal.ca.

Can I sample practice questions before subscribing?

Yes. You can download a free 30-question sample mock exam PDF with full step-by-step answer explanations. A subscription unlocks all 1200 questions, spaced-repetition review, and AI tutoring.

What's the best way to study for the Red Seal exam?

Consistent daily practice beats cramming. Read our Founder's Exam Prep Journey Blog Series to see how daily spaced repetition works in practice.

What does a subscription cost?

We offer a 7-Day Pass ($9.99 CAD one-time), a Monthly Pass ($29.99 CAD/month), and a 3-Month Pass with Free-Until-You-Pass Guarantee ($69.99 CAD one-time). All plans include daily adaptive practice, spaced-repetition review, and AI Journeyperson Tutor coaching.

What extra practice comes with the 3-Month Pass?

The 3-Month Pass adds two study tools for Sheet Metal Worker (308A). Practice by Block lets you pick any Major Work Activity on the official blueprint and drill it 18 questions at a time. Exhibit Booklet Practice gives you 12 questions that make you read tables, catalogs, test records and a supply duct plan view, with a worked explanation for every answer.