The Four Principles of Odor Control: A Professional Approach to Controlling Cleaning and Restoration Odors

In the cleaning and restoration industry, successful odor control is more than just masking unpleasant smells, often referred to as malodors. It requires a strategic, science-based approach rooted in industry standards. According to the ANSI/IICRC S100 Standard for Professional Cleaning of Textile Floor Coverings, “There are four deodorizing principles: remove the source (as practical); clean off significant residue, recreate the conditions of penetration using an appropriate odor counteractant, and seal as necessary.”

To effectively eliminate malodors, each principle must be understood and addressed. Skipping or overlooking any principle can result in incomplete removal and the eventual return of odors — and unhappy clients!

Principle #1: Remove the Source

The first and most critical step in odor control is identifying the source material that is expressing odors — such as urine-saturated carpet, fire-related smoke residues in an airmass, or mold behind wallpaper — and removing it. Whether surface-bound or airborne, these contaminants must be located and removed whenever practical. Without source removal, further deodorization efforts are unlikely to succeed.

Technicians must be thorough in their inspection, recognizing that some sources may be hidden within or under building materials, in inter-cavity spaces, or on furnishings and textiles.

Principle #2: Clean Contaminated Surfaces

Once the source is removed, all contaminated surfaces must be meticulously cleaned or physically removed, depending on the contamination type and IICRC Standard recommendations. Professional-grade cleaning agents—especially those containing surfactants—help dissolve, emulsify, and suspend residual soils for effective removal.

Many cleaning products also incorporate deodorizing agents to further assist in eliminating remaining odor-causing compounds.

It’s important to note that deeply penetrated contaminants may resist complete removal. If this is the case, Principle #4: Seal as Necessary, may be your final step.

Principle #3: Recreate the Conditions of Penetration

It is necessary to recreate the conditions under which the odor penetrated the material surface environment using the appropriate deodorizer and method. This is often done using deodorizers in liquid, solid, or vapor phase for airborne contamination and residual odors.

These agents are specifically formulated to counteract or modify odor molecules. When properly selected and applied, these treatments mimic the original pathway of odor intrusion, ensuring deeper and more effective odor eradication. This principle is frequently misunderstood or skipped—leading to incomplete deodorization.

Principle #4: Seal If Necessary

In cases where odors persist despite cleaning and deodorizing, professional sealing compounds may be used as a final step. These restoration-grade, non-porous sealers lock residual odor molecules into the surface, preventing them from being released into the environment—especially under conditions of elevated heat or humidity.

Sealers are available in both water-based and solvent-based formulations and may be clear or tinted. Surfaces must be thoroughly cleaned and dried before application. Once sealed, surfaces can typically be painted after 24–72 hours.

Conclusion

Odor control in the cleaning and restoration industry is a precise, multi-step process rooted in science, best practices, and Standard recommendations. When properly executed, the four principles—source removal, surface cleaning, deodorization, and sealing—offer a reliable path to permanent odor elimination.

By adhering to these guiding principles, technicians can deliver results that restore comfort, safety, and trust for their clients.