kSIST FprEN 17762:2026

kSIST FprEN 17762:2026 is the Slovene adoption of the draft European Standard prEN 17762 from CEN. It specifies a laboratory method for determining copper in ammonium nitrate fertilizers of high nitrogen content, and it is written for testing laboratories, fertilizer manufacturers, and anyone who needs a standardised result for product control or specification checking.

The document uses either atomic absorption spectrophotometry (AAS) or inductive coupled plasma - optical emission spectroscopy (ICP-OES) after acid dissolution of the sample. In practice, it tells the laboratory how to prepare the test solution, calibrate the instrument, correct for the blank, and report the copper content in mg/kg.

What does kSIST FprEN 17762:2026 specify?

kSIST FprEN 17762:2026 specifies a method for determining the copper content in ammonium nitrate fertilizers of high nitrogen content. It also applies to certain fertilizing product blends when inorganic fertilizers are the largest component by mass, volume, or in liquid form by dry mass.

The scope gives a practical rule for mixed products: if inorganic fertilizer is not the highest share, the European Standard for the highest-share component applies. If components are present in equal quantity, the user chooses which standard to apply. That matters when a product contains several matrices that can affect the analytical result.

The document is organized into clauses 1 to 11 and one informative annex.

What are the key requirements of kSIST FprEN 17762:2026?

Scope, sampling, and sample preparation

Clause 1 limits the method to ammonium nitrate fertilizers of high nitrogen content and to certain blends. Clause 7 says sampling is outside the method itself, but sample preparation shall follow EN 1482-2, and EN 1482-1 is given as the recommended sampling method.

This matters because the result depends on getting a representative sample that has not been damaged or changed in transport or storage. A laboratory result is only useful if the submitted sample reflects the product being assessed.

Principle and reagents

Clause 4 states that the sample is dissolved in dilute hydrochloric acid and copper is measured by AAS or ICP-OES. Clause 5 requires analytical-grade reagents and specifies the water quality, acids, copper-free ammonium nitrate, hydrogen peroxide, and copper stock and standard solutions.

This gives the analytical basis of the method and the solution chemistry needed for calibration. In practice, the laboratory must prepare standards and blanks consistently, because those solutions anchor the measurement.

Apparatus and measurement

Clause 6 names the main equipment, including an atomic absorption spectrophotometer with a copper lamp at 324,8 nm, or an ICP-OES instrument. The clause also specifies the balance, flasks, beaker, and copper-free filter paper.

The method is therefore designed around standard laboratory instrumentation, but the chosen instrument changes the exact measurement setup. For AAS, the wavelength and oxidising air-acetylene flame are specified; for ICP-OES, the analyst selects the optimal copper wavelength.

Procedure, blank, and calibration

Clause 8 describes how to prepare the test solution, including digestion with hydrochloric acid, evaporation to dryness, redissolution, filtration, and dilution to volume. It also requires a blank solution, at least five calibration solutions, and triplicate measurements.

This is the core of the method in practice: the laboratory has to treat the sample and blank in parallel, build a calibration curve, and read the copper concentration from that curve. The procedure also includes a safety warning about acid fumes and recommends working in a fume cupboard.

Expression of results, precision, and reporting

Clause 9 says to calculate copper content with the test portion mass, all dilutions, and the blank, and to report the result in mg/kg. Clause 10 gives repeatability and reproducibility information and points to Annex A for the inter-laboratory study. Clause 11 lists the minimum test report contents, including the method used, result, dates, and any unusual operating details.

The precision section is important when results are close to a limit value or near the limit of quantification (LoQ). In those cases, the document says the sample should be spiked to check reliability, and the LoQ should be well below any limit value if one applies.

What terms does kSIST FprEN 17762:2026 define?

• Atomic absorption spectrophotometry (AAS) - an instrumental method used here to measure copper by absorption at a specified wavelength.
• Inductive coupled plasma - optical emission spectroscopy (ICP-OES) - an alternative instrumental method used here to measure copper from the emitted light of an excited plasma.
• Blank solution - a solution prepared without the sample so the analyst can correct the final result for background contribution.
• Repeatability - the closeness of results obtained under the same laboratory conditions in a short time.
• Reproducibility - the closeness of results obtained in different laboratories with different operators and equipment.
• Limit of quantification (LoQ) - the concentration region where the document says extra checking may be needed to confirm a reliable result.

Who uses kSIST FprEN 17762:2026?

kSIST FprEN 17762:2026 is used by fertilizer testing laboratories, quality control teams, and producers of ammonium nitrate fertilizers. It is also relevant for buyers, auditors, and regulators who need a common test method for copper content.

In practice, users apply it for product release, incoming inspection, conformity assessment, and dispute testing. It is also useful where a fertilizer blend contains several components and the laboratory needs a defined way to choose the correct standard.

What changed in kSIST FprEN 17762:2026 from the previous edition?

kSIST FprEN 17762:2026 supersedes CEN/TS 17762:2022. The foreword states these significant technical changes: the technical specification was adopted as a European Standard; the scope and normative references were updated; distilled water characteristics were added; copper solution concentrations were added; sampling and sample preparation were updated; the measurement step was updated; Clause 10 on precision and Annex A with inter-laboratory study results were added; and the bibliography was updated.

Which standards are used with kSIST FprEN 17762:2026?

• EN 1482-2 - gives the general sample preparation provisions used for this method.
• EN 1482-1 - is cited as the recommended sampling method.
• prEN 12944-1 - provides general fertilizer-related terms and definitions.
• prEN 12944-2 - provides additional fertilizer terms and definitions.
• ISO 5725-1 - is used for the precision calculations reported for the inter-laboratory study.
• ISO 5725-2 - is used for the repeatability and reproducibility calculations.

What does the kSIST FprEN 17762:2026 document contain?

The document contains a defined analytical workflow, from sample dissolution through calibration and measurement to result calculation. It also includes the apparatus list, reagent specifications, and a detailed test report checklist.

Annex A presents the inter-laboratory study behind the precision data, including statistical results for two samples. Table 1 in Clause 10 gives repeatability and reproducibility limits, which are the values laboratories use to judge whether two results are close enough to be considered consistent.