Foam Cleaning Overview
There are many reasons to apply chemicals as foam instead of as liquid spray. To appreciate these benefits, it is helpful to understand the different types of foam. Different cleaning objectives and available utilities (compressed air) will determine which type of foam equipment is needed. Keep in mind that foaming may not be the ideal application method for your particular chemical type or application needs (spraying or fogging may be more appropriate).
Types of Foam
Foam is simply a chemical solution that has been mixed with air. Foam consistency (wet versus dry) plays a key role in maximizing the effectiveness of foam cleaning procedures.
- Airless Foam does not require compressed air. Airless foam is a "wet" foam which allows the chemical solution to penetrate soil more thoroughly. Wet, clinging foam is created by drawing atmospheric air into the chemical solution via an Airless Foam Wand.
- Air Assisted Foam requires compressed air. Air-assisted foam is "dry" foam which clings to surfaces longer than airless foam. However, if the foam is too dry it will not clean effectively. Rich, clinging foam is created by injecting compressed air into the chemical solution.
Benefits of Foam
- Foam clings to surfaces longer than liquid spray and increases chemical contact time.
- Foaming expands the chemical, allowing less chemical to cover more surface area.
- Foam prevents over-application by providing visual confirmation of coverage.
- Foam is projected at a lower pressure than liquid spray and can be used on more sensitive surfaces.
Foam Quality Troubleshooting
Not seeing the results you were hoping for? Please consider these Frequently Asked Questions as well as the unit-specific troubleshooting guide in the Installation & Operation Instructions.
- Is the chemical designed for foaming?
- Foaming agents can be added to enhance the foaming properties of non-foaming or low-foaming chemicals.
- Is the chemical designed to foam well at the desired concentration (dilution ratio)?
- It may be necessary to increase the chemical concentration or add foaming agent to enhance the overall foaming properties of the solution.
- Is the compressed air too high or too low? (Air-assisted only.)
- Too much compressed air will result in very dry foam, which will not clean effectively. Too much compressed air can also cause the discharge hose to "buck" and foam output to sputter. Too little compressed air will result in watery foam, which will not cling to surfaces as well as slightly drier foam. Adjust the air valve as needed to make the foam wetter or drier.
Foam Too Dry
Not Enough Foaming Chemical
(Air-Assisted or Airless)