Compostable
Compostable
The term compostable refers to the principle by which a product, after use, can be disposed of with organic waste and recovered in composting plants. In fact, through the composting process, waste and waste derived from the kitchen, garden and other compostable products can be transformed into a new material which takes the name of compost.
However, the concept of compostable should not be confused with that of biodegradable; It often happens that these two terms are used interchangeably. In reality, these are two distinctive characteristics of the materials.
A material is defined as biodegradable when the substance of which it is composed is able to decompose into smaller substances through the activity of microorganisms and then recirculate in nature.
If this biological process is complete, there is a total conversion of the starting organic substances into simple inorganic molecules such as water and carbon dioxide.
The term compostable is applied, at EU level, above all to the characteristics that some packaging materials must have in order to be accumulated in landfills and then convertible, through a series of biochemical processes, into compost.
Compost is an organic, biologically stable, inert, odorless substance mainly made up of humus, active microorganisms and microelements. Compost is often reused in the agronomic field, for example as a fertilizer.
For this reason, packaging is defined as compostable when it satisfies all the requirements defined in the Italian technical standard, harmonized at European level, by UNI EN 13432 of 2002.
EN 13432 is a harmonized standard of the European Standardization Committee published in 2000. This standard regulates the characteristics that packaging must possess in order to be defined as biodegradable and compostable. The term “compostable” refers to the ability of the packaging to be recovered through organic recycling.
This standard is entitled “Requirements for packaging recoverable through composting and biodegradation – Test scheme and evaluation criteria for the final acceptance of packaging”.
Compostability Requirements –
Therefore, in order to meet the compostability requirements, a material must comply with the provisions of the European standard.
The standard has been prepared under a mandate from the European Commission to provide presumption of conformity with the essential requirements of the Packaging and Packaging Waste Directive, 94/62/EC.
Therefore, according to the EN 13432 standard, a material to be defined as “compostable” must possess the following requirements:
– biodegrade by at least 90% in 6 months; these values must be tested with the standard method EN 14046 (similar to the international standard ISO 14855);
– in contact with organic materials for a period of 3 months, the mass of the material must be made up of at least 90% of fragments smaller than 2 mm; these values must be tested with the standard method EN 14045;
– the material must not have negative effects on the composting process;
– low concentration of heavy metals added to the material;
– pH values within established limits;
– salt content within established limits;
– concentration of volatile solids within established limits;
– concentration of nitrogen, phosphorus, magnesium and potassium within the established limits.
If the material meets all these requirements, it can be defined as compostable, and reported in the specifications, and usable in materials to produce compost.