308A Study Guide 2026
Everything you need to pass the 308A exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.
📋 308A Exam Format at a Glance
📚 308A Topics to Study (39)
✍️ Sample 308A Questions & Answers
1. What is the purpose of a 'flexible connector' between the air handling unit and the ductwork?
Flexible connectors (typically fabric or rubber) isolate mechanical vibration from the AHU fans, preventing it from transmitting through the rigid ductwork. They also accommodate thermal expansion.
2. What is the standard third-angle projection used in Canadian and North American drawings?
Third-angle projection places the top view above the front view, the right side view to the right of the front view, and the left side view to the left. Each view shows the object as seen from that direction.
3. What happens to accuracy if too few division points are used when developing a curved surface pattern?
Fewer division points mean the curved surface is approximated with fewer straight-line segments, resulting in visible flat spots. More divisions improve accuracy but increase layout complexity.
4. What is the advantage of using self-drilling screws (Tek screws) for sheet metal assembly?
Self-drilling (Tek) screws have a drill-point tip that pierces and drills through the sheet metal, then the threads tap into the hole — all in one operation. This eliminates the need for pre-drilling.
5. What is the purpose of a 'heat sink' when welding thin sheet metal?
Heat sinks (copper bars, aluminum blocks, or wet rags) placed near or behind the weld joint absorb excess heat, reducing the risk of burn-through and minimizing warping on thin sheet metal.
6. Which type of respiratory protection is recommended when power-grinding stainless steel in a shop environment?
Grinding stainless steel produces fine hexavalent chromium particles, a known carcinogen; a half-face respirator with P100 filters provides adequate protection for shop environments.