Content Team

by Monday, 21st Oct 2024

Share with

Plastic Seeds

Understanding ASTM Standards for Plastics

Plastics play a very crucial role as a material in the manufacturing and development of different products in various industries. They provide effective, flexible, and long-lasting solutions to packaging and automotive pieces, medicines, or household articles. However, such plastics must undergo testing and validation processes to ensure that they are safe and fulfill all the performance aspects as well as the regulations set by appropriate authorities. Being a highly recognized international organization, ASTM International has developed standards that guarantee specific properties, durability, and microbial resistance of plastics. According to the ASTM standards for plastics, the particular plastic material is supposed to be intact under various environmental conditions.

Exploring ASTM Standard G21

ASTM G21 standard, also known as the “Standard Practice for Determining Resistance of Synthetic Polymeric Materials to Fungi,” is a commonly used test method under ASTM standards for plastics for evaluating plastic material resistance to fungi.ASTM Standard G21 aims to quantify the ability of synthetic polymeric materials, like plastics, coatings, and rubber, to resist attack by fungi that can cause mold in favorable conditions.

  •  Importance in Industrial Applications: ASTM G21 helps to test the resistance of plastics in construction, electronics, and consumer goods that can be exposed to moist environments. Products include plastic components in air-conditioning systems, electrical enclosures, and outdoor furniture. In such applications, very high resistance toward fungal action is important because material degradation would detrimentally affect the long-lasting durability they possess.

Understanding ASTM Standard D3273

ASTM  D3273 standard is a test method  to measure the resistance of building materials such as drywall, insulation, and interior surfaces of buildings to mold growth under controlled conditions. This standard offers a means for establishing how well a material will withstand conditions favorable to mold growth.

  • Purpose: To test for mold resistance of materials commonly found in construction, especially in a moist or humid environment.
  • Importance: The growth of mold can cause structural damage and health issues- including allergy and respiratory problems, and reduce the life material. ASTM D3273 ensures building materials meet minimum industry requirements concerning mold resistance, ensuring a safer and healthier environment.

Comparative Analysis: ASTM G21 vs. D3273

While both ASTM G21 and ASTM D3273 are designed to assess the resistance of plastic materials to fungal and mold growth, there are some key differences between the two ASTM standards for plastics that manufacturers should consider.

1. Scope of Testing

  • ASTM G21 standard  -Assesses the resistance of synthetic polymeric material, including plastic and rubber, to fungal growth.
  • ASTM D3273 standard -Assesses the resistance of building materials such as drywall and insulation to mold growth under high-humidity conditions.

2. Applicability

  • ASTM G21– ASTM G21 is used to test the fungal resistance of plastics intended for use in damp environments including building materials, medical devices, and outdoor products.
  • ASTM D3273-It is used mainly in the construction industry in order to ensure that the materials that are used for both dwellings and commercial buildings are resistant to mold growth.

3. Testing Environment
ASTM G21 Test: Exposes  materials to fungi under controlled conditions that favour growth, with moderate levels of humidity and temperature for a fixed time period

ASTM D3273:Exposure for 28 days under conditions promoting mold growth, with high humidities to create moisture-prone conditions in building materials.

Significance in Product Quality Assurance

The use of ASTM standards for plastics like G21 and D3273 is critical for maintaining product quality, particularly in industries where plastics are exposed to environmental factors that could lead to microbial degradation. It includes:

1. Enhancing Product Durability
By adhering to these ASTM standards for plastics, manufacturers can produce plastic materials that withstand the rigors of their intended environments. Products that resist fungal and mold growth last longer and perform better over time, reducing the likelihood of replacements or recalls.

2. Ensuring Consumer Safety
Mold and fungi not only damage materials but also pose significant health risks, particularly in indoor environments. Products that pass the test as per ASTM standards for plastics, such as ASTM G21 and D3273 testing help to ensure healthier living and working conditions, contributing to better indoor air quality and reducing the potential for respiratory issues caused by mold exposure.

Regulatory Compliance and Industry Standards

  •  Meeting Regulatory Requirements
    Many countries require that materials applied to construction, electronics, and consumer products to be coated with plastics must pass ASTM specifications so that they can be sold. Passing the test as per ASTM standards for plastics, such as ASTM G21 and D3273, indicates that a product complies with the regulation; therefore, when these products are being sold, no market entry obstruction will be experienced because of non-compliance.
  • Building Industry Credibility

Manufacturers can let consumers and the trade know that the products they deliver have met standards that assure quality control. This would enhance the reputation of the brand and is likely to increase buyer confidence in products that deliver performance with durability.

Practical Applications and Decision-making

The type of ASTM standard to test the product is chosen by manufacturers according to the application intended for the material.

  • ASTM G21 would be suitable for plastics that are going to be used outdoors or in industrial environments where exposure to fungi may become a concern.
  • ASTM D3273 would be more suitable for interior applications where surface mold growth is a risk due to high humidity.

Conclusion: 

In today’s competitive market, plastic products must meet the plastics testing standards to ensure the highest standards of quality, durability, and safety. Plastics are tested as per ASTM G21 and ASTM D3273 standards for resistance against fungi and mold, constituting the basis on which the evaluation of such products is carried out thus ensuring consumer safety.

At MIS, we provide thorough testing services such as ASTM G21 for plastic products, ensuring your products meet the highest standards. Contact us today to learn more about our testing services.Plastics play a very crucial role as a material in the manufacturing and development of different products in various industries. They provide effective, flexible, and long-lasting solutions to packaging and automotive pieces, medicines, or household articles. However, such plastics must undergo testing and validation processes to ensure that they are safe and fulfill all the performance aspects as well as the regulations set by appropriate authorities. Being a highly recognized international organization, ASTM International has developed standards that guarantee specific properties, durability, and microbial resistance of plastics. According to the ASTM standards for plastics, the particular plastic material is supposed to be intact under various environmental conditions.

Exploring ASTM Standard G21

ASTM G21 standard, also known as the “Standard Practice for Determining Resistance of Synthetic Polymeric Materials to Fungi,” is a commonly used test method under ASTM standards for plastics for evaluating plastic material resistance to fungi.ASTM Standard G21 aims to quantify the ability of synthetic polymeric materials, like plastics, coatings, and rubber, to resist attack by fungi that can cause mold in favorable conditions.

  •  Importance in Industrial Applications: ASTM G21 helps to test the resistance of plastics in construction, electronics, and consumer goods that can be exposed to moist environments. Products include plastic components in air-conditioning systems, electrical enclosures, and outdoor furniture. In such applications, very high resistance toward fungal action is important because material degradation would detrimentally affect the long-lasting durability they possess.

Understanding ASTM Standard D3273

ASTM  D3273 standard is a test method  to measure the resistance of building materials such as drywall, insulation, and interior surfaces of buildings to mold growth under controlled conditions. This standard offers a means for establishing how well a material will withstand conditions favorable to mold growth.

  • Purpose: To test for mold resistance of materials commonly found in construction, especially in a moist or humid environment.
  • Importance: The growth of mold can cause structural damage and health issues- including allergy and respiratory problems, and reduce the life material. ASTM D3273 ensures building materials meet minimum industry requirements concerning mold resistance, ensuring a safer and healthier environment.

Comparative Analysis: ASTM G21 vs. D3273

While both ASTM G21 and ASTM D3273 are designed to assess the resistance of plastic materials to fungal and mold growth, there are some key differences between the two ASTM standards for plastics that manufacturers should consider.

1. Scope of Testing

  • ASTM G21 standard  -Assesses the resistance of synthetic polymeric material, including plastic and rubber, to fungal growth.
  • ASTM D3273 standard -Assesses the resistance of building materials such as drywall and insulation to mold growth under high-humidity conditions.

2. Applicability

  • ASTM G21– ASTM G21 is used to test the fungal resistance of plastics intended for use in damp environments including building materials, medical devices, and outdoor products.
  • ASTM D3273-It is used mainly in the construction industry in order to ensure that the materials that are used for both dwellings and commercial buildings are resistant to mold growth.

3. Testing Environment


ASTM G21 Test
: Exposes  materials to fungi under controlled conditions that favor growth, with moderate levels of humidity and temperature for a fixed time period

ASTM D3273:Exposure for 28 days under conditions promoting mold growth, with high humidities to create moisture-prone conditions in building materials.

Significance in Product Quality Assurance

The use of ASTM standards for plastics like G21 and D3273 is critical for maintaining product quality, particularly in industries where plastics are exposed to environmental factors that could lead to microbial degradation. It includes:

1. Enhancing Product Durability
By adhering to these ASTM standards for plastics, manufacturers can produce plastic materials that withstand the rigors of their intended environments. Products that resist fungal and mold growth last longer and perform better over time, reducing the likelihood of replacements or recalls.

2. Ensuring Consumer Safety
Mold and fungi not only damage materials but also pose significant health risks, particularly in indoor environments. Products that pass the test as per ASTM standards for plastics, such as ASTM G21 and D3273 testing help to ensure healthier living and working conditions, contributing to better indoor air quality and reducing the potential for respiratory issues caused by mold exposure.

Regulatory Compliance and Industry Standards

  •  Meeting Regulatory Requirements


Many countries require that materials applied to construction, electronics, and consumer products to be coated with plastics must pass ASTM specifications so that they can be sold. Passing the test as per ASTM standards for plastics, such as ASTM G21 and D3273, indicates that a product complies with the regulation; therefore, when these products are being sold, no market entry obstruction will be experienced because of non-compliance.

  • Building Industry Credibility

Manufacturers can let consumers and the trade know that the products they deliver have met standards that assure quality control. This would enhance the reputation of the brand and is likely to increase buyer confidence in products that deliver performance with durability.


Practical Applications and Decision-making

The type of ASTM standard to test the product is chosen by manufacturers according to the application intended for the material.

  • ASTM G21 would be suitable for plastics that are going to be used outdoors or in industrial environments where exposure to fungi may become a concern.
  • ASTM D3273 would be more suitable for interior applications where surface mold growth is a risk due to high humidity.

Conclusion: 

In today’s competitive market, plastic products must meet the plastics testing standards to ensure the highest standards of quality, durability, and safety. Plastics are tested as per ASTM G21 and ASTM D3273 standards for resistance against fungi and mold, constituting the basis on which the evaluation of such products is carried out thus ensuring consumer safety.

At MIS, we provide thorough testing services such as ASTM G21 for plastic products, ensuring your products meet the highest standards. Contact us today to learn more about our testing services.

Similar Blogs

Subscribe to Our Newsletter

Get industry insights, exclusive offers, and expert tips, straight to your inbox!

Ready to test your product?

Microbe Investigations Switzerland