 Standard specifications create a pass or fail scenario whereas standard test methods identify the specific testing parameters for facilitating specific time frames and toxicity of biodegradable tests on plastics.ASTM D5511-18 - Standard Test Method for Determining Anaerobic Biodegradation of Plastic Materials Under High-Solids Anaerobic-Digestion Conditions

ASTM D5526-18 - Standard Test Method for Determining Anaerobic Biodegradation of Plastic Materials Under Accelerated Landfill Conditions

Both standards above indicate that a minimum of 70% of the material should have biodegraded by 30 days (ASTM D5511-18) or the duration of the testing procedure (ASTM D5526-18) to be considered biodegradable under anaerobic conditions.ASTM D6400 - Standard Specification for Labeling of Plastics Designed to be Aerobically Composted in Municipal or Industrial Facilities

ASTM D6868 - Standard Specification for Labeling of End Items that Incorporate Plastics and Polymers as Coatings or Additives with Paper and Other Substrates Designed to be Aerobically Composted in Municipal or Industrial Facilities

Both standards above outline procedures for testing and labelling biodegradability in aerobic composting conditions.