SIST EN 15924:2011

SIST EN 15924:2011 is the Slovenian adoption of EN 15924:2011 from CEN. It specifies a wet-sieving method for determining the fineness of grinding of soft natural phosphates, so laboratories can measure how much material passes the 0,125 mm and 0,063 mm sieves. The result is reported as a percentage by mass and is used in fertilizer testing and quality control.

What does SIST EN 15924:2011 specify?

SIST EN 15924:2011 specifies a laboratory method for soft natural phosphates only: determination of fineness of grinding by wet sieving. It is organized into clauses 1 to 10, covering the scope, references, terms, principle, sampling note, reagents, apparatus, procedure, calculation and expression of result, and test report.

Clause 4 explains the measuring principle. Clauses 5 to 8 describe how to prepare and sieve the sample. Clause 9 gives the result calculations, and clause 10 defines what the report has to record.

What are the key requirements of SIST EN 15924:2011?

• Clause 4: use wet sieving rather than dry sieving. The standard says fine particles can agglomerate, which makes dry sieving difficult. In practice, the method uses water to separate particles more reliably and to measure the grind fineness in a way that reflects the real state of the product.

• Clause 5: keep sampling and sample preparation under control. Sampling itself is not part of the method, and sample preparation follows EN 1482-2. EN 1482-1 is given as the recommended sampling method. This matters because the result depends on getting a representative laboratory sample before the sieve test starts.

• Clauses 6 and 7: use the specified reagent and equipment. The method uses a 1 % sodium hexametaphosphate solution, sieves with 0,063 mm and 0,125 mm apertures, collecting containers, a glass funnel, 250 ml beakers, and a drying oven. This fixes the test setup so different laboratories work in the same way.

• Clause 8: follow the wet-sieving procedure in order. The test portion is about 50 g, weighed to the nearest 0,05 g. The sample is washed through the stacked sieves with a small jet of cold water until the water is nearly clear, then the retained material is dried at (150 ± 5) °C to constant weight. If lumps are present, the standard calls for dispersing the sample in sodium hexametaphosphate and repeating the analysis.

• Clause 9: calculate two fineness values from the retained masses. One result is for material passing 0,125 mm and the other for material passing 0,063 mm. In practice, this gives a clear picture of how much of the phosphate is finely ground and how much remains coarser.

• Clause 10: report the result with traceable test details. The report includes the method reference, sample identification, sampling date and procedure if known, completion date, the fineness result, and any optional steps or unusual events. That record helps when results are reviewed, compared, or challenged.

What terms does SIST EN 15924:2011 define?

• Fineness of grinding - the share of material fine enough to pass the specified sieves, expressed as a percentage by mass.
• Wet sieving - sieving with water instead of dry screening, used here to reduce the effect of particle agglomeration.
• Laboratory sample - the prepared sample taken forward for the test portion in accordance with EN 1482-2.
• Test portion - the weighed part of the laboratory sample used for one determination, about 50 g in this method.
• Residue - the material retained on a sieve after wet sieving and drying.
• Mass fraction - the way the result is expressed in clause 9 for the 0,125 mm and 0,063 mm fractions.

Who uses SIST EN 15924:2011?

This standard is used by fertilizer laboratories, producers of soft natural phosphates, quality managers, and inspection or purchasing teams that need an agreed method for checking grinding fineness. It is relevant when product release, incoming inspection, or technical documentation depends on a reproducible sieve test.

What changed in SIST EN 15924:2011 from the previous edition?

SIST EN 15924:2011 supersedes CEN/TS 15924:2009. The foreword states that the former Technical Specification was adopted as a European Standard and editorially revised.

Which standards are used with SIST EN 15924:2011?

• EN 1482-2 - gives the sample preparation method used before testing.
• EN 12944-1:1999 - supplies general vocabulary for fertilizers and liming materials.
• EN 12944-2:1999 - supplies fertilizer-specific vocabulary used in the document.
• EN 1482-1 - is cited as the recommended sampling method in the bibliography.
• Regulation (EC) No 2003/2003 - is cited in the bibliography with Annex IV, method 7.2, showing the method’s link to the EU fertilisers framework.

What does the SIST EN 15924:2011 document contain?

Clauses 1 to 10 give the method from scope through reporting. The middle clauses describe the principle, reagent, apparatus, and the wet-sieving steps, including washing the sieves, handling lumps, and drying the residues to constant weight. Clause 9 gives the calculation approach for the two sieve fractions, and clause 10 lists the report items needed for traceability. The bibliography points to EN 1482-1 and Regulation (EC) No 2003/2003 Annex IV method 7.2.