ISO 15958:2019 pdf download – Fertilizers — Extraction of water soluble phosphorus.
1 Scope This document specifies a method for the extraction of water soluble phosphorus. The method is applicable to all fertilizers, including compound fertilizers, where water soluble phosphorus is to be determined. 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. EN 1482-2, Fertilizers and liming materials — Sampling and sample preparation — Part 2: Sample preparation EN 12944-1, Fertilizers and liming materials and soil improvers — Vocabulary — Part 1: General terms EN 12944-2, Fertilizers and liming materials and soil improvers — Vocabulary — Part 2: Terms relating to fertilizers 3? Terms? and? definitions For the purposes of this document, the terms and definitions given in EN 12944-1 and EN 12944-2 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/ 4 Principle Extraction in water by shaking under the specified conditions. 5 Sampling Sampling is not part of the method specified in this document. A recommended sampling method is given in EN 1482-1. Sample preparation shall be carried out in accordance with EN 1482-2. Grinding of the laboratory sample is recommended for homogeneity reasons. 6 Reagents 6.1 Water, distilled or demineralized.
7 Apparatus 7.1? 500? ml? graduated? flask, e.g. Stohmann. 7.2? Rotary? shaker, 35 to 40 turns per minute. 7.3? Dry? pleated? filter, phosphate free. 8 Procedure 8.1 Test portion Weigh, to the nearest 0,001 g, 5 g of the laboratory sample and place it in a graduated flask (7.1). 8.2 Extraction Add to the test portion in the flask 450 ml of water (6.1), the temperature of which shall be between 20 °C and 25 °C. Shake in the rotary shaker (7.2) for 30 min. Then make up to the mark with water, mix thoroughly by shaking and filter through a dry pleated filter (7.3). 9 Test report The test report shall contain at least the following information: a) all information necessary for the complete identification of the sample; b) the test method used with reference to this document including its publication year, i.e. ISO 15958:2019; c) test results obtained; d) the date of sampling and sampling procedure (if known); e) the date when the analysis was finished; f) whether the requirement of the repeatability limit has been fulfilled; g) all operating details not specified in this document, or regarded as optional, together with details of any incidents occurred when performing the method, which might have influenced the test result(s).
ISO 15958:2019 pdf download – Fertilizers — Extraction of water soluble phosphorus
