Odor control has become a consumer-demanded performance feature in modern textiles, including activewear, intimates, and home textiles. As consumers increasingly expect products to stay fresh, brands and retailers are driven to adopt odor control technologies that meet their performance requirements. Malodors in textiles often arise when bodily secretions are broken down by bacteria into odorous compounds. To evaluate the effectiveness of odor control treatments, it is critical to understand and utilize standardized test methods that are fit-for-purpose. However, with multiple test methods available, selecting the appropriate method can be challenging. This article explores four odor control test methods—AATCC TM211, AATCC TM216, ISO 17299-2, and ISO 17299-3—and provides guidance on selecting the best approach for your specific application.

AATCC TM211: Evaluating Bacterial Odor Reduction in Antibacterial-Treated Textiles

AATCC TM211 specifically measures the reduction of bacterial odor in textiles treated with antibacterial finishes. Unlike standard antibacterial efficacy tests, this method directly evaluates odor reduction. It uses ammonia-generating organisms as surrogates, measuring how effectively treated textiles reduce ammonia—a key component of bacterial odor. Importantly, it assesses odor reduction capacity rather than simply bacterial counts.

Advantages:

• Directly targets bacterial odor, a primary source of textile malodor.
• Measures odor reduction capacity, not just bacterial presence.
• Specifically designed for antibacterial-treated textiles.
• Uses ammonia, a significant bacterial odor marker.

Limitations:

• Not suitable for non-biocidal odor management technologies.
• Limited to ammonia measurement, potentially missing other odor types.
• Does not assess odor adsorption, only reduction of bacterial-generated ammonia.

AATCC TM216: Measuring Odor Absorbency in Textiles Using Human Malodor Markers

Developed in 2023 by AATCC Committee RA31, AATCC TM216 measures the odor absorbency of textiles using isovaleric acid (IVA), representative of human body odor. The method accounts for inherent fabric absorbency and uses standardized conditions—IVA concentration, inoculation volume, sample size, and conditioning period—tailored to the material’s composition for reproducible results.

Advantages:

• Quantitatively evaluates durably-bound non-biocidal odor management technologies.
• Uses IVA, a realistic marker for human malodor.
• Correlates with established methods like AATCC TM211 and IACM 0714.

Limitations:

• Does not measure bacterial odor reduction.
• Limited to odor absorbency; may not capture the full odor spectrum.
• Recently developed, so not yet widely adopted.

ISO 17299-2: Detector Tube Method for Volatile Odor Chemical Analysis

ISO 17299-2 uses commercially available detector tubes to measure the concentration of specific odor chemicals, such as ammonia, acetic acid, methyl mercaptan, and hydrogen sulfide. The method compares the concentration of these chemicals in containers with and without textile specimens, providing a simple and cost-effective approach for evaluating volatile deodorizers.

Advantages:

• Simple, cost-effective testing using widely available detector tubes.
• Suitable for a variety of volatile odor chemicals.
• Quick results with straightforward analysis.

Limitations:

• Not suitable for evaluating durably-bound odor control technologies.
• Limited chemical range per detector tube, restricting odorant diversity.
• Less precise than advanced analytical techniques like gas chromatography.

ISO 17299-3: Gas Chromatography Method for Comprehensive Odor Analysis

ISO 17299-3 employs gas chromatography (GC) for a detailed analysis of odor chemicals, including indole, isovaleric acid, nonenal, and acetic acid. By comparing odorant concentrations in controlled environments with and without test specimens, this method offers high precision and is considered the most general approach for laboratory odor testing.

Advantages:

• Measures a broader range of odorants with high precision.
• Suitable for general odor testing of volatile deodorizers.
• Highly accurate due to gas chromatography’s analytical capabilities.

Limitations:

• Requires specialized, costly equipment.
• More complex and time-consuming than other methods.

Selecting the Appropriate Odor Control Test Method

Choosing the right odor control test depends on the technology and performance requirements:

• For Antibacterial Finishes: Choose AATCC TM211 to directly measure bacterial odor reduction through ammonia analysis.
• For Durably-Bound Non-Biocidal Technologies: AATCC TM216 offers precise measurement of odor absorbency using human malodor markers.
• For Volatile Deodorizers (Basic Evaluation): ISO 17299-2 provides a simple, cost-effective solution for assessing specific volatile odor components.
• For Volatile Deodorizers (Comprehensive Evaluation): ISO 17299-3 delivers highly accurate, broad-spectrum odor analysis via gas chromatography.

Accurate odor control testing is essential for validating textile performance claims and ensuring customer satisfaction. While AATCC TM211, AATCC TM216, ISO 17299-2, and ISO 17299-3 all assess odor reduction, each serves a distinct purpose depending on the technology applied and the target odor. Understanding these differences ensures that the chosen test method aligns with product goals and market expectations.

For more information and for expert guidance, contact the IAC regarding the best approach for your technology or treated articles.