Ventilation calculations
ASP written lesson, 9 min read. ASP Domain 1: Mathematical Calculations
AI-drafted from the cited rules and fact-checked against them. Study aid, not site-specific safety advice. The official rule controls.
What you'll learn
- Calculate air velocity from a smoke-tube test using V = D/T
- Find a round duct's diameter from its circumference
- Size dilution airflow with q_d, Q_d and the mixing factor Km
- Apply the hood distance and stack height rules
- Avoid the common mix-ups in ventilation formulas
What this lesson covers
This lesson covers the ventilation arithmetic the exam keeps returning to: smoke-tube velocity, duct diameter from a tape measure, dilution airflow with the mixing factor, and the hood and stack distance rules. Each one is a short formula or a single number, and each is easy to get backwards under time pressure.
This lesson is included with a pass
Written lessons come with every ASP pass, along with the video lessons, the question bank, mocks and the tutor. $80 per exam or $143 for all three, for 180 days.