Antimicrobial plastics are engineered to resist the colonization and growth of microorganisms including bacteria, mold and fungi. These materials are very important in environments where maintenance of hygiene is essential such as hospitals, kitchens, and public places. To ensure these materials perform as expected, testing standards for antimicrobial plastics such as ASTM G21 and ASTM D3273 are used. This article delves into the significance of antifungal plastics, the roles of ASTM G21 and ASTM D3273 standards, key differences and similarities between the two standards and guidance on selecting the appropriate standard for specific applications.
Key Differences and Similarities between ASTM G21 vs ASTM D3273
Similarities
Origin of standard
Both ASTM G21 and ASTM D3273 standards for antifungal plastics testing were developed by the American Society for Testing and Materials (ASTM) to fulfill the need for standardized evaluation of materials’ resistance to fungal growth. This is required to address both industry and regulatory requirements for material safety and durability.
Compliance needs
Compliance with ASTM G21 and ASTM D3273 standards for antifungal plastics testing is essential across industries that manufacture or use synthetic polymers and interior coatings. This compliance ensures that the materials used in these sectors are capable of withstanding fungal attacks thereby guaranteeing their longevity, safety, and effectiveness. Regulatory bodies and industry guidelines reference these standards as part of the quality control and certification process highlighting their role in maintaining public health and safety.
Mandatory test strains
ASTM G21 standard uses five mandatory fungal strains namely Aspergillus niger, Penicillium pinophilum, Chaetomium globosum, Gliocladium virens, and Aureobasidium pullulans. This specific approach makes sure the material is tested against different types of fungi giving a complete analysis of its fungal resistance.
ASTM D3273 standard also uses three similar mandatory fungal strains namely Aureobasidium pullulans, Aspergillus niger, and Penicillium Sp.
Differences between ASTM G21 vs ASTM D3273
Methodology
The test methods specified by ASTM G21 and ASTM D3273 standards for antifungal plastics are based on their targeted applications and test organisms.
ASTM G21 involves inoculating a prepared spore suspension of specific fungi on the test material placed in a petri dish over minimal salts agar and incubating it for a recommended duration of time under the conditions favorable for fungal growth. The test analyzes the resistance of materials to fungal growth after the incubation period.
ASTM D3273 utilizes an environmental chamber to simulate a severe interior environment conducive to mold growth. Test materials are exposed to controlled temperature and humidity conditions maintained in the chamber which favors the growth of sporulating fungi. The resistance of test materials to mold is evaluated over a set period. This method replicates the conditions, the material would face in an indoor setting focusing on the surface growth of mold on coatings
Scope of products
The types of products that can be tested as per ASTM G21 and ASTM D3273 standards for antifungal plastics also differentiate the two standards
ASTM G21 applies broadly to synthetic polymeric materials in various forms including but not limited to molded articles, sheets, rods, and films.
ASTM D3273 is specifically designed for testing the resistance of interior coatings to mold growth. This narrower focus targets products like paint films used in indoor environments and address concerns regarding their vulnerability to mold in high humidity conditions
Choosing between ASTM G21 vs ASTM D3273
Choosing between ASTM G21 and ASTM D3273 standards for antifungal plastics depends on the test material and the type of microbial resistance needed.
ASTM G21 is suitable for evaluating the fungal resistance of various types of synthetic polymeric materials and products that are exposed to environments susceptible to fungal growth. ASTM D3273 is created for interior coating making it the preferred choice for paints and similar finishes used in places where mold resistance even in humid indoor conditions is essential.
While deciding which test method to choose, it is essential to consider parameters such as the specific environment where the material will be used and the nature of microbial threats it will face.
At MIS, we specialize in the testing of antimicrobial plastics using a diverse range of microbes.
Our state-of-the-art testing facilities are equipped to perform comprehensive antimicrobial testing. We are a team of highly experienced microbiologists and technical specialists who employ their extensive research, analytical, and interpretative skills to meticulously assess the antimicrobial efficacy and safety of products under specific conditions.
For detailed information on ASTM G21 vs ASTM D3273 testing services, please reach out to our team experts today.
