BS EN 12225:2020 pdf free.Geosynthetics一Method for determining the microbiological resistance by a soil burial test.
BS EN 12225 This document specifies a method for the determination of the microbiological resistance of geosynthetics including those of natural fibres and biodegradable polymers by a soil burial test.NOTE Experience and exhumation of geosynthetics which had performed successfully, in some cases for more than two decades, indicate that geosynthetics made out of synthetic materials are generally resistant against microbial initiated decay. It can therefore be expected that most of these products commercially available at the present time will pass the soil burial test successfully and it is probably not necessary to submit them all to this test independent of their function. However, if the requirements for appropriate functioning of the geosynthetics demand proof of microbiological resistance or if they are manufactured from newly developed polymers whose resistance is in any doubt, the soil burial test can provide additional information.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.EN 12226, Geosynthetics 一General tests for evaluation following durability testing EN ISO 291, Plastics一Standard atmospheres for conditioning and testing (ISO 291) EN ISO 11721-1:2001, Textiles一Determination of the resistance of cellulose-containing textiles to micro-organisms一Soil burial test一Part 1: Assessment of rot-retardant finishing (ISO 11721-1:2001) EN ISO 13934-1, Textiles – – Tensile properties of fabrics一Part 1: Determination of maximum force and elongation at maximum force using the strip method (ISO 13934-1)The water content is determined by drying 100 g of the soil in a thin layer at (104土1) °C until the mass remains constant to within 1 % (normally 24 h). If the water content of the test soil is too high,dry it in thin layers in laboratory atmosphere. Do not heat since this might affect the microflora. If the water content of the soil is too low the volume of solvent that is required for the wetting of soil can be determined according to EN ISO 11721-1:2001, Annex A, A.2. A solution of 1 g ammonium nitrate and 0,2 g dipotassium-hydrogen phosphate per 1 I of water shall be used to increase the water content.To establish a constant microbial activity of the test soil, the soil shall be acclimatised prior to the soil burial test. The method consists of a preliminary incubation for at least 28 days at 2 90 % relative humidity and about 28 °C for new soil sample. Alternatively, the soil can be acclimated for at least 56 days with the test climate of≥90 % relative humidity and about 26 °C. If the same soil material is used more than once, then for each new test set up half of the old material shall be replaced by new soil material in the manner described above.BS EN 12225 pdf downlaod.