M2 · area 04 · subtopic 0402
Duct and Plenum Use and Application
3 percent of the M2 Commercial Mechanical Inspector exam. At 50 questions, that is roughly 1 to 2 questions, each with about 144 seconds of budget including the lookup.
- Exam
- M2
- Area
- Duct Systems
- Weight
- 3%
- Questions
- ~1 to 2
What this subtopic covers
Correct use and application of ducts and plenums; sizing of supply and return air ducts.
How to drill it
- Find the chapter of the International Mechanical Code that carries this subject and read it once for structure, not retention: what lives here, what gets sent elsewhere, which tables exist.
- Write your own plain-language phrases for what this subtopic covers, then note the code's terms beside them. Mismatches between the two columns are exactly where exam questions cost you time.
- Run timed lookups: pick a requirement named in the descriptor above, start a stopwatch, find the governing text in your book, stop. Log the seconds. Past two minutes is a miss even when the answer is right.
- Weight your reps to the number above. Roughly 1 to 2 questions means this subtopic deserves repeated timed reps inside its area session.
2024 International Residential CodeThe book that sits on the table for two hours. Match it to the version you register for.Check priceThe rest of area 04: Duct Systems (12%)
| Subtopic | Weight | |
|---|---|---|
| 0401 | Duct Construction and Installation | 4% |
| 0403 | Smoke and Fire Dampers | 5% |
The kit that goes on the table
2024 IRCThe book itself
2021 IRCIf you register on 2021
2024 Fast-TabsPlace them yourself
Construction Master ProFeet-inch math, no errorsMatch the book and tabs to the edition you register for.Confirm which, first.
The 120-second study sheet
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