How many Air Filtration units do you need for your space: A Helpful Guide

How many Air Filtration units do you need for your space: A Helpful Guide

First Step in Choosing an Air Purifiers

Determining Air Exchange Rate (AER) and CFM Calculation

Applications and Recommended Air Exchange Rates:

  • Welding: 4-6 minutes
  • Grinding: 6 minutes
  • Plasma Cutting collection over a wet table: 6-8 minutes
  • Diesel Smoke: 8 minutes
  • Foundry: 6-8 minutes
  • Plastic Smoke: 8-10 minutes
  • Wood Working: 8-10 minutes
  • General Ambient Air: 10 minutes

Step 1: Determine Air Exchange Rate ( AER)

  • Choose the appropriate Air Exchange Rate (AER) from the provided table above based on your application.

Step 2: Calculate Total Cubic Feet of your space

  • Total Cubic Feet = L x W x H (maximum height 20’)
    • Where:
      • L = length of workspace (feet)
      • W = width of workspace (feet)
      • H = height of ceiling in the workspace (feet)

Step 3: Calculate CFM

  • CFM = Total Cubic Feet / Air Exchange Rate (AER)


  • Workspace dimensions: 100’ long x 60’ wide x 18’ tall
  • Total Cubic Feet: 100 x 60 x 18 = 108,000 cubic feet
  • AER for Welding (medium use): 5
  • CFM = 108,000 / 5 = 21,600 CFM

Second Step in Choosing a Commercial Air Purifiers

Consideration of Installation and Mobility

  • Evaluate ease of installation and mobility.
  • Placement is crucial for optimal performance.
  • Consider existing HVAC systems, cranes, or fans in place.
  • Anticipate future changes, growth, and possible relocation.

Third Step in Choosing an Air Purifiers

Efficiency Considerations

  • Prioritize efficiency to control running and maintenance costs.
  • Look for lower horsepower ratings.
  • Choose a system that is self-sustaining, recirculating air within the shop.

Fourth Step in Choosing an Air Purifiers

Cost and Availability of Replacement Filters

  • Be aware of filter replacement costs.
  • Choose a system with common filter sizes and efficiencies.
  • Cirrus Filtration uses common sizes, providing flexibility in filter replacement.

Fifth Step in Choosing an Air Purifiers

Reputation and Customer Satisfaction

  • Choose a company with a strong reputation.
  • Consider experience in building, selling, and maintaining air cleaners.
  • Seek customer feedback and satisfaction.
  • Ensure prompt maintenance and parts availability.

Cirrus Filtration's Commitment

  • Cirrus Filtration emphasizes providing the best solutions and customer service.
  • Extensive engineering background for building, selling, and maintaining products.
  • Popular models available for consideration.
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