Fungal Resistance Testing


Microchem Laboratory is an industry-leading provider of fungal resistance testing services. The laboratory conducts fungal resistance tests on products ranging from drywall to paints, coatings, and sealants.

These services are crucial to the building and construction industry, because lab-tested materials prevent mold growth and improve health.

The lab has dedicated test chambers and fungal incubators, and maintains more than 40 species of fungi. The scientists are skilled with regard to the conduct of standard antifungal tests, including ASTM G21 and ASTM D3273.

Microchem Laboratory understands the commercial importance of mold and mildew resistance tests. To make sure the laboratory's clients are satisfied, several steps are taken:

  • Fast turnaround - Most fungal resistance tests run for 28 days. To prevent delays, the laboratory makes sure that studies are not unnecessarily delayed during setup or reporting.
  • Reliable control performance - In order to measure the ability of a test surface to resist fungal attack, a control surface is usually included in the test for comparison. Microchem takes steps to ensure consistent, reliable control results.
  • Imaging -The most common fungal resistance tests rely on a visual rating system to determine product performance. Test reports include color photos to supplement determinations made by our fungal resistance testing specialists.

Fungal Resistance Test Methods

The two most requested test methods are ASTM G21 and ASTM D3273, both of which are excellent means of evaluating a product's resistance to fungi. In addition, we perform AATCC 30, ASTM E1428, Federal Standard 191A Method 5760, and Military Standard 810G Method 508.6. Below, you will find a complete list of our fungal resistance testing services as well as links to general information about fungi and some comparisons between different test methods.

Microchem's scientists are knowledgeable and helpful. If your company is not sure what fungal resistance test is most appropriate, we can help you choose. To help, the company has put together a handy comparison of the four main fungal resistance test methods. If your firm already knows which test is most suitable to evaluate the antifungal characteristics of your product, simply request a price quote.

Helpful Information about Fungal Resistance and Antifungal Agents

Fungi can grow almost anywhere where they have moisture, a food source, and warm temperatures. Fungal growth causes a wide range of unpleasant effects on surfaces, such as staining, degradation, corrosion, and foul odor. For this reason, many products now integrate anti-fungal substances in order to protect consumers and extend the life and performance of their products.

An anti-fungal substance is any product that is meant to prevent fungal growth. Anti-fungal substances can be added directly into a product to protect it from fungal growth. Anti-fungal substances can also be applied to the outside surface of an object (a coating) in order to protect it from fungal growth, or added to the entire object directly during manufacturing.

 

How is Fungal Resistance Testing Different from Fungicide Testing?

Fungal resistance testing is sometimes confused with fungicide testing. The information below identifies the differences between the two very different tests.

Fungal resistance refers to a surface or coating's ability to prevent fungal growth. Fungal resistance tests involve spraying or inoculating fungal spores onto the surface, placing it in an environment favorable to fungal growth, then observing it over a long period of time and measuring the extent of fungal growth. Performance in the test is determined by the amount of visible fungal growth on the surface, in consideration of the amount of fungal growth observed on the control surface.

Fungicide testing (fungicidal efficacy testing) is different than fungal resistance testing. Fungicides are chemicals designed to kill fungal spores and hyphae - the filamentous part of molds - quickly. Most germicides bearing fungicidal claims are tested using a modified version of the AOAC Germicidal Spray Test, where fungal spores are dried on to a hard surface, then sprayed with the test substance and allowed a contact time of less than 10 minutes. After the contact time, the surfaces are harvested and the number of surviving fungi are counted and compared to the number present before treatment. Determination of fungicidal efficacy is done by dilution and plating, then counting colonies on agar.

 

Fungi Commonly Used for Antifungal Testing

  • Aspergillus brasiliensis
  • Aspergillus niger
  • Aspergillus versicolor
  • Aspergillus flavus
  • Aureobasidium pollulans
  • Chaetomium globosum
  • Cladosporium cladosporioides
  • Penicillium pinophilum
  • Trichoderma pseudotkoningii
  • Trichoderma virens

Materials with Inherent Resistance to Fungal Attack

Some materials and products are inherently resistant to fungal attack, typically because they do not contain carbon-containing molecules (a necessary food source for fungi) or because the carbon-containing molecules are resistant to degradation by fungal enzymes. The list below presents materials with inherent resistance to fungal attack:

  • Glass
  • Low density polyethylene plastic
  • High density polyethylene plastic
  • Acrylic plastic
  • Styrofoam
  • Rubber

Materials Inherently Susceptible to Fungal Attack

Most of the fungal resistance tests done at Microchem Laboratory evaluate the ability of paper-based (cellulosic) and coatings to withstand fungal attack. The list below summarizes materials that frequently require the addition of antifungal chemicals to remain intact over the course of their intended use:

  • Paints (as dry coatings)
  • Drywall
  • Paper construction products
  • Caulks and sealants
  • Textiles

How to Select a Fungal Resistance Testing Laboratory

  • Fungal resistance tests naturally take a month or more to conduct, so a good testing lab will expedite the process on the front and back end to ensure a speedy overall project.
  • Antifungal agents are a class of antimicrobial agents. Only specialized labs have the understanding of antimicrobial testing necessary to ensure robust science and reproducible study results.
  • Antifungal tests such as ASTM D3273 and ASTM G21 require specialized equipment and a relatively large amount of laboratory space. Larger, established laboratories such as Microchem are best equipped to conduct such work and are able to handle large study volumes if necessary.
  • Highly technical antifungal test methods often require input from the performing scientist or customization to meet the needs of a given product. Select a laboratory with approachable, helpful microbiologists.

Starting a Fungal Resistance Test with Antimicrobial Test Labs is Fast and Easy

With its specialized facility and scientific expertise, Microchem Laboratory is an industry-leading provider of fungal resistance tests. To evaluate the ability of your product to withstand fungal attack, just contact the lab by email or request a price quote.