What is ASTM D6400, ASTM D6868 and ASTM D5338?

ASTM D6400 and ASTM D6868 are standards for compostability. ASTM D5338 is the relevant testing method for these two standards. 

ASTM D6400 is the standard specification for labeling plastics. 

ASTM D6868 is the standard specification for labeling end items that incorporate plastics and polymers as coatings or additive with paper and other substrates.

ASTM D5338 is the testing method to determine aerobic biodegradation of plastic materials under controlled composting conditions, incorporating thermophilic temperatures.