oSIST prEN 17766:2026

oSIST prEN 17766:2026 is a SIST draft European standard for extracting elements from organic and organo-mineral fertilizers with water before their determination. It covers boron (B), cobalt (Co), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), phosphorous (P) and zinc (Zn), and the extracts are measured using prEN 17774.

What does oSIST prEN 17766:2026 specify?

oSIST prEN 17766:2026 specifies a water-extraction procedure for organic and organo-mineral fertilizers so the resulting extract can be used for elemental analysis. The same extract can also be used for other elements if the laboratory needs that.

The standard also applies to certain fertilizing product blends made from at least two listed component types when organic fertilizers or organo-mineral fertilizers are the largest share by mass, volume, or dry mass for liquids. If another component type is the largest share, the standard for that dominant component applies; if the shares are equal, the user chooses the applicable standard. The document is organized into clauses 1 to 9: scope, normative references, terms and definitions, principle, sampling and sample preparation, reagents, apparatus, procedure, and test report.

What are the key requirements of oSIST prEN 17766:2026?

Decide whether the method applies

Clause 1 limits the method to the stated fertilizer types and eligible blends. In practice, this means the analyst has to classify the product correctly before choosing the test method, especially for mixtures that contain several fertilizing product categories.

Use a representative, prepared sample

Clause 5 says sampling is not part of the method and points to EN 1482-1 and EN 1482-3 for recommended sampling, while sample preparation follows EN 1482-2. This matters because a damaged or non-representative sample can make the extraction result misleading.

Use the specified water and clean reagents

Clause 6 requires water with a specific conductivity not higher than 0,2 mS/m at 25 °C and free from the elements to be determined. Nitric acid is used if extracts need acidification for storage, so the lab must keep reagent contamination under control.

Use suitable equipment and avoid contamination

Clause 7 calls for a rotary or horizontal eccentric shaker, extraction vessels, ash-free filter paper of recognized quality, and cleaned glassware or plastic ware. For boron determination, contact with borosilicate glass should be minimized, which is important because trace contamination can distort low-level results.

Follow the extraction conditions exactly

Clause 8 requires the prepared sample to be extracted with water at 20 ± 2 °C, shaken for 60 min, and kept from settling during extraction. The extract is filtered if needed, the first portion of filtrate is discarded, and a blank test solution is prepared the same way as the sample.

Hand the extract to the determination step correctly

Clause 4 says the extracts are analysed according to prEN 17774. Clause 8 adds that measurement should be done the same day when possible, or the extract may be kept at 4 ± 3 °C for up to two days and then acidified if storage is longer. This gives the laboratory a clear handover point between extraction and measurement.

Record the work in the test report

Clause 9 requires the report to identify the sample, cite this method and its year, note sampling details if known, state when extraction finished, and record any deviations or incidents. That documentation is what lets another lab understand how the result was produced.

What terms does oSIST prEN 17766:2026 define?

• Fertilizing product blends - Mixtures of at least two listed component types, where the choice of standard depends on which category is present in the highest proportion.
• Organic fertilizers - The product category covered by the scope when it is the dominant part of the blend.
• Organo-mineral fertilizers - The other main product category covered by the scope when it is the dominant part of the blend.
• Representative sample - A sample that still reflects the product being tested after sampling, transport and storage.
• Blank test solution - A control solution prepared by the same extraction steps as the sample to check contamination or background.
• Inductively coupled plasma atomic emission spectrometry (ICP-AES) - The measurement technique named in the introduction for determining the extracted elements.

Who uses oSIST prEN 17766:2026?

Laboratory analysts, fertilizer manufacturers, quality managers, and regulatory testers use oSIST prEN 17766:2026 for checking elemental content in organic and organo-mineral fertilizers and in eligible blends. It is aimed at routine laboratory extraction work before instrumental determination.

What changed in oSIST prEN 17766:2026 from the previous edition?

oSIST prEN 17766:2026 will supersede CEN/TS 17766:2022. The stated technical changes are:

• adoption of the CEN Technical Specification as a European Standard
• introduction added
• scope updated, including clarification on fertilizing product blends and the analytical method to be used
• reagents updated with nitric acid
• apparatus updated with more detail and a remark on laboratory glassware quality
• procedure updated with more detail and specific adaptations
• bibliography updated

Which standards are used with oSIST prEN 17766:2026?

What does the oSIST prEN 17766:2026 document contain?

oSIST prEN 17766:2026 contains the scope, referenced terminology, the extraction principle, reagent and apparatus lists, the step-by-step water extraction procedure, and test report requirements. The practical core is Clause 8, which tells the laboratory how to weigh the sample, extract it with water, filter the extract, handle storage, and pass the extract to the determination method. The bibliography also points to related sampling and measurement documents used with this method.