Testing standards of antimicrobial treatment for textile products

First Published: April 2023

As the demand for hygiene and sanitation increases, antimicrobial treatments have become more common in the textile industry. Complying with relevant standards plays a vital role in ensuring textile products with antimicrobial treatments are effective and safe for consumers, as well as meeting any commercial claims made.

In this article, we will highlight testing standards for the antimicrobial treatment of textile products, particularly AATCC 100, AATCC 30, and AATCC 147 standards.

What is the purpose of antimicrobial treatment for textile products?

Antimicrobial treatments are increasingly common in the textile industry nowadays. These treatments can provide benefits such as improving hygiene, controlling odor, and preserving textile products.

In real-life scenarios such as hospital linens, food industry textiles, sports apparel and footwear and other items that require a high level of cleanliness, antimicrobial treatments can help to prevent the growth of bacteria and other microorganisms. They can also help to control unpleasant odors caused by microbial growth and extend the life cycle of textile products by preventing the growth of microorganisms that can degrade or damage the fabric over time.

Brands and retailers can differentiate their products by adding antimicrobial treatments. However, they need to ensure that their products meet relevant safety and efficacy standards. They also must ensure that commercial claims placed on their products are properly substantiated with relevant testing that demonstrates so and that the antimicrobial treatments withstand a certain degree of use over time (i.e. efficacy after a given number of washes needs to be substantiated as well).

Below, we will focus on the three best-known standards developed by the American Association of Textile Chemists and Colorists (AATCC) that are used to test the effectiveness of antimicrobial treatments on textile products, named AATCC 100, AATCC 30, and AATCC 147.

AATCC 100:2004 - Test Method for Antibacterial Finishes on Textile Materials

AATCC 100 is a standard method that measures the effectiveness of antibacterial finishes on textile materials.

This standard tests both bacteriostatic activity (growth inhibition) and bactericidal activity (killing of bacteria) of the sample.

The test involves exposing a treated textile sample to a bacterial suspension and then measuring the reduction in bacterial growth on the sample over a 24 hours of contact.

Antibacterial activity is determined by comparing the reduction in the viable count of bacteria on the treated sample with the untreated sample.

AATCC 30:2004 - Test Method for Antifungal Activity, Assessment on Textile Materials

AATCC 30 is a standard method that measures the effectiveness of antifungal treatments on textile materials.

The purpose of AATCC 30 is to determine the ability of a treated textile material to resist the growth of fungi. The test involves exposing a treated textile sample to a suspension of fungal spores and then measuring the reduction in fungal growth on the sample over time.

There are four types of testing under this standard:

• AATCC 30 part 1 is a soil burial test method. It is used for textile materials that are intended to come into direct contacts with soil, such as tents and sandbags.
  
  Treated and untreated are exposed in the soil beds for 7 days to determine the fungal activity.
  
  
  
• AATCC 30 part 2 is an agar plate test against Chaetomium globosum, evaluating the rot resistance of cellulose-containing textile materials that do not come in contact with soil.
  
  This test will take 10 to 14 days and then evaluate the breakage strength and antifungal resistance of the treated fabric sample compared with the untreated sample.
  
  
  
• AATCC 30 part 3 is an agar plate test against Aspergillus niger which is a fungus. This test is used to assess the efficacy against the growth of this fungus.
  
  
• This test will take 7 days with glucose for non-cellulosic materials and 14 days without glucose for cellulosic materials. Microscopic examination of fungal growth will be conducted on the samples.
  
  
  
• AATCC 30 part 4 is a humidity jar, mixed spore suspension test. It is designed to determine the efficacy of controlling mildew and non-pathogenic fungal growth. It is used for waterproof textile materials intended for outdoor and above-ground use.
  
  This test will take 14 days for non-coated cellulosic materials and 28 days for non-cellulosic or coated cellulosic textiles.

AATCC 147 - Antibacterial Activity of Textile Materials: Parallel Streak

AATCC 147, also known as the Parallel Streak method, is a standard method to determine the bacteriostatic activity of diffusible antimicrobial finishes on textile materials.

The method is relatively easy to perform and provides reproducible results. It offers an alternative to the more involved AATCC 100, making it a great screening tool.

However, this is a qualitative test method (while AATCC 100 is a quantitative method) and it does not apply to textile materials that cannot be diffused through bacterial growth medium or that have been impregnated with any antibacterial-neutralising substances.

How can Eurofins Softlines & Hardlines help?

We provide a range of tests to evaluate the efficacy of antimicrobial finishes using a variety of microbiological testing methods that conform to either international standards or the client’s specific requirements.

To ensure a comprehensive assessment, we utilise the most widely-recognised and accepted testing methods for antibacterial and antifungal evaluations in the industry.

For more details, learn more about our Microbiology Testing Services.