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This document specifies the definitions and requirements for solid wall pipes with smooth internal and external surfaces, extruded from the same formulation throughout the wall, fittings and the system of unplasticized poly(vinyl chloride) (PVC-U) piping systems in the field of non-pressure underground drains and sewers for wastewater. NOTE 1 Products complying with this document can also be used in non-pressure underground drains and sewers for surface water. This document also specifies test methods and test parameters. This document is applicable to: - solid wall pipes and fittings which are intended to be used buried underground outside the building structure reflected in the marking of the products by “U”, and - solid wall pipes and fittings which are intended to be used buried underground both outside (application area code “U”) and within the building structure reflecting on the marking of products by “UD”. NOTE 2 Multilayer pipes with different formulations throughout the wall and foamed core pipes are covered by EN 13476-2 [1]. This document covers a range of pipe and fitting sizes, stiffness classes, and gives recommendations concerning colours. NOTE 3 It is the responsibility of the purchaser or specifier to make the appropriate selection from these aspects, taking into account their particular requirements and any relevant national regulations and installation practices or codes. In conjunction with CEN/TS 1401 2 [7] it is applicable to PVC-U pipes and fittings, their joints and to joints with components of other plastics and non-plastics materials intended for buried piping systems for non-pressure underground drains and sewers. NOTE 4 Pipes, fittings and other components conforming to any of the plastics product standards listed in Annex C can be used with pipes and fittings conforming to this document, provided they conform to the requirements for joint dimensions given in Clause 10 and to the requirements of Table 16.

This document defines test methods and criteria for distinguishing intrinsically biodegradable plastic materials from those that are persistent. Biodegradability is inferred from biodegradation tests conducted under aerobic conditions, i.e. under the conditions typically found in most natural habitats. Plastics that undergo ultimate biodegradation under aerobic conditions in a manner similar to natural polymer materials are defined as biodegradable plastics. This document describes a method for distinguishing between non-biodegradable plastics, which do not biodegrade even when environmental conditions are favourable for biodegradation (including aerobic conditions), and biodegradable plastics, i.e. those that biodegrade upon contact with active microorganisms when environmental conditions are favourable for biodegradation.

The aim is to demonstrate ultimate aerobic biodegradability of plastic materials, i.e. the intrinsic potential for conversion to carbon dioxide, water and biomass by aerobic microorganisms in an oxygen-rich environment, which is representative of most natural environments.

The potential for biodegradation should be verified using alternative tests and criteria, if a deposition in a permanent anaerobic environment (e.g. deep subsurface environments, wetlands and swamps, anoxic zones in oceans and lakes) is expected.

NOTE          Currently, there are no methodologies or criteria available to verify accumulation due to the lack of biodegradation of plastics in such anaerobic habitats.

The plastic materials identified as intrinsically biodegradable following this document can be used in the design of products with a high risk of dispersion whenever the use of biodegradable components is searched by the designer. Intrinsically non-biodegradable components are not susceptible to biodegradation and therefore cannot be removed from the environment by the action of micro-organisms. This factor tends to increase the residence time of products in the environment. In addition, their eventual degradation, mainly due to abiotic factors, results in persistent fragments (microplastics).

The test scheme described in this document is not specific to any particular application. Rather, it is a framework methodology that can be used in different industries to identify biodegradable plastics that can be used to make different types of products and for different applications. For the characterisation and environmental assessment of products placed on the market containing plastics identified as biodegradable according to this document, reference is made to the specific product standards, where available. This document only deals with the definition of intrinsic biodegradability of plastic materials, without defining the hazard of the products, which requires a specific assessment that is beyond the scope of this document. The rate of biodegradation of a plastic object as a function of environmental conditions cannot be determined from this document. Therefore, this document is not sufficient to carry out an analysis of the ecological risk associated with the dispersal of products, as this requires an assessment of the intrinsic hazard, of the environmental fate, in addition to the assessment of biodegradability.

The methodology described in this document does not apply to applications covered by mandatory regulations.

This document specifies the dimensions, the method of sampling, the preparation of the test specimens and the conditions for performing the tensile test in order to determine the short-term tensile welding factor. A tensile test can be used in conjunction with other tests (e.g. bend, tensile creep, macro) to assess the performance of welded assemblies, made from thermoplastics materials. The test is applicable to welded semi-finished products made from thermoplastics materials filled or unfilled, but not reinforced, irrespective of the welding process used.