ISO 23977-1:2020 pdf download

ISO 23977-1:2020 pdf download.Plastics — Determination of the aerobic biodegradation of plastic materials exposed to seawater
1 Scope
This document specifies a laboratory test method for determining the degree and rate of the aerobic biodegradation level of plastic materials. Biodegradation is determined by measuring the CO 2 evolved from plastic materials when exposed to seawater sampled from coastal areas under laboratory conditions. The conditions described in this document might not always correspond to the optimum conditions for the maximum degree of biodegradation, however this test method is designed to give an indication of the potential biodegradability of plastic materials. NOTE This document addresses plastic materials but can also be used for other materials.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 5667-3, Water quality — Sampling — Part 3: Preservation and handling of water samples
ISO 8245, Water quality — Guidelines for the determination of total organic carbon (TOC) and dissolved organic carbon (DOC)
ISO 10210, Plastics — Methods for the preparation of samples for biodegradation testing of plastic materials
ISO 10523, Water quality — Determination of pH
ISO 11261, Soil quality — Determination of total nitrogen — Modified Kjeldahl method
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1 pelagic zone
water body above the seafloor
Note 1 to entry: It is also referred to as the open water or the water column
Note 2 to entry: The surface of the pelagic zone is moved by wind-driven waves, is in contact with the atmosphere and exposed to sunlight. With increasing depth pressure increases, temperature decreases, and light and surface wave energy are attenuated.
[SOURCE: ISO 22766:2020, 3.4]
3.2 dissolved inorganic carbon
part of the inorganic carbon in water which cannot be removed by specified phase separation
Note 1 to entry: Phase separation can be achieved for example by centrifugation at 40 000 m⋅s −2 for 15 min or by membrane filtration using membranes with pores of 0,2 μm to 0,45 μm diameter.
[SOURCE: ISO 14852:—, 3.4]
3.3 theoretical amount of evolved carbon dioxide
maximum theoretical amount of carbon dioxide evolved after completely oxidizing a chemical compound, calculated from the molecular formula
Note 1 to entry: It is expressed as milligrams of carbon dioxide evolved per milligram or gram of test compound.
[SOURCE: ISO 14852:—, 3.5]