Finishing worked example

Powder Booth Airflow at 99% fan and filter efficiency: a worked example

Push fan and filter efficiency up to 99% and the picture changes. This example computes every intermediate figure at that operating point. Use this calculator for practical powder coating or surface finishing planning, quoting, troubleshooting, or line setup.

The inputs for this scenario

  • Booth open face area: 100 ft² (unchanged)
  • Target capture velocity: 75 ft / min (unchanged)
  • Fan and filter efficiency: 99 % (raised for this scenario; the documented default is 90)

Working through the calculation

  • Applying the documented formula (Effective rate = base × factor × efficiency) to the inputs above produces each figure below.
  • At this operating point the engine returns 7,425 CFM for effective rate, the number this scenario is built around.
  • At this operating point the engine returns 7,500 CFM for base rate.
  • At this operating point the engine returns 75 CFM for loss to inefficiency.
  • At this operating point the engine returns 99 % for efficiency.

How this compares with the baseline

  • Against the tool's baseline example, where fan and filter efficiency sits at 90% and the headline result is 6,750 CFM, this scenario comes in 10% above the baseline at 7,425 CFM.
  • It multiplies open face area by target capture velocity to get base CFM, then derates by fan-and-filter efficiency to give effective airflow. The value of this scenario is the size of the gap it exposes: that gap, priced out over a year, is the budget you can justify spending to close it.

Results at a glance

  • Effective rate: 7,425 CFM (headline result)
  • Base rate: 7,500 CFM
  • Loss to inefficiency: 75 CFM
  • Efficiency: 99 %

Run it with your numbers

  • Every input above is editable in the live Powder Booth Airflow calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.