oSIST prEN 17777:2026

• Abstract:

  This document specifies references to the methods for the determination of the following specific elements in organic and organo-mineral fertilizers:; Determination of the total phosphorus content;; Determination of the total potassium content;; Determination of the total calcium content;; Determination of the total magnesium content;; Determination of the total sodium content;; Determination of the total sulphur content;; Determination of the inorganic arsenic content;; Determination of the cadmium content;; Determination of the total chromium content;; Determination of the total mercury content;; Determination of the total nickel content;; Determination of the total lead content;; Determination of the total copper content;; Determination of the total zinc content;; Determination of the water-soluble calcium content;; Determination of the water-soluble magnesium content;; Determination of the water-soluble sodium content;; Determination of the water-soluble sulphur content.; This document specifies references to the methods for the determination of the following specific elements in organo-mineral fertilizers:; Determination of the water-soluble phosphorus content;; Determination of the water-soluble potassium content;; Determination of the neutral ammonium citrate soluble phosphorus content; Determination of the formic acid soluble phosphorus content;; Determination of the total boron content;; Determination of the total cobalt content;; Determination of the total iron content; Determination of the total manganese content; Determination of the total molybdenum content;; Determination of the water-soluble boron content;; Determination of the water-soluble cobalt content;; Determination of the water-soluble copper content;; Determination of the water-soluble iron content;; Determination of the water-soluble manganese content;; Determination of the water-soluble molybdenum content;; Determination of the water-soluble zinc content.; The scope of the standards referenced in this document specifies in which cases the method is also applicable to blends.

• Status: Not Published
• Public Enquiry End Date: 01-Apr-2026
• ICS: 65.080 - Fertilizers
• Technical Committee: KAT - Soil quality
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 11-Feb-2026
• Due Date: 01-Jul-2026
• Completion Date: 29-Apr-2026
• Directive: 2019/1009 - Regulation (EU) 2019/1009 of the European Parliament and of the Council of 5 June 2019 laying down rules on the making available on the market of EU fertilising products and amending Regulations (EC) No 1069/2009 and (EC) No 1107/2009 and repealing Regulation (EC) No 2003/2003 (Text with EEA relevance)
• Mandate: M/564 - Fertilising products in support of Regulation (EU) 2019/1009
• Mandate: M/564 AMD 1 - amending Implementing Decision C(2020) 612 as regards certain harmonised standards and standardisation deliverables, deadlines for their adoption and the duration of the validity of the standardisation request
• Mandate: M/564 AMD 2 - Commission Implementing decision amending Implementing Decision C(2020)612 as regards harmonised standards, the deadlines for the adoption of those standards and the duration of the validity of the standardisation request to the European Committee for Standardisation as regards the EU fertilising products in support of Regulation (EU) 2019/1009 of the European Parliament and of the Council
• Ref Project: FprEN 17777 - Organic and organo-mineral fertilizers - Determination of specific elements

• Revises: SIST-TS CEN/TS 17777:2023 - Organic and organo-mineral fertilizers - Determination of specific elements
• Effective Date: 01-Mar-2026

oSIST prEN 17777:2026 is a SIST draft European Standard for organic and organo-mineral fertilizers. It specifies which analytical methods are used to determine specific elements and element fractions, so laboratories, manufacturers, and conformity-assessment users know which test standard to apply for each analyte.

The document is mainly a method-reference standard: it does not set the chemistry itself, but points to the relevant extraction, digestion, and measurement standards used for compliance work, including products covered by Regulation (EU) 2019/1009.

What does oSIST prEN 17777:2026 specify?

oSIST prEN 17777:2026 specifies references to the methods for determining specific elements in organic and organo-mineral fertilizers. It also states that the scope of the referenced methods tells users when the same method applies to fertilizing product blends.

The document is organized into five clauses, an informative Annex ZA, and a bibliography:

• Clause 1 - Scope
• Clause 2 - Normative references
• Clause 3 - Terms and definitions
• Clause 4 - Sampling and sample preparation
• Clause 5 - Determination of specific elements
• Annex ZA - relationship with Regulation (EU) 2019/1009

Annex	What it covers
Annex ZA	Relationship between this European Standard and the essential requirements of Regulation (EU) 2019/1009 for EU fertilising products

What are the key requirements of oSIST prEN 17777:2026?

oSIST prEN 17777:2026 works by assigning each analyte to one or more referenced methods in Clause 5. In practice, users select the method chain that matches the element and whether the sample is measured as total content, water-soluble content, or soluble in a specified reagent.

Total elements and trace elements

For total phosphorus, potassium, calcium, magnesium, sodium, sulphur, chromium, copper, manganese, and molybdenum, Clause 5 points to prEN 17768:2026. For cadmium, nickel, lead, zinc, boron, cobalt, and iron, the document combines prEN 17768:2026 with prEN 17770:2026. This means the sample is first prepared by the referenced digestion route, then measured with the specified determination method.

Water-soluble elements

For water-soluble calcium, magnesium, sodium, sulphur, phosphorus, potassium, boron, cobalt, copper, iron, manganese, molybdenum, and zinc, Clause 5 points to prEN 17766:2025. In practice, this is the route for nutrients that are intended to be available in water extracts, so the user tests the dissolved fraction rather than the whole material.

Phosphorus in special soluble fractions

Clause 5 gives two additional phosphorus fractions: neutral ammonium citrate soluble phosphorus and formic acid soluble phosphorus. These are determined using prEN 17779:2026 or prEN 17767:2026 together with prEN 17774:2026, so the user applies a specific extraction chemistry before the final measurement.

Element-specific methods

Inorganic arsenic is determined in accordance with prEN 17775:2026, and mercury is determined using prEN 17769:2026 together with prEN 17768:2026. These specific routes matter because arsenic and mercury need dedicated determination methods rather than only a general multi-element approach.

Sampling and sample preparation

Clause 4 states that sampling and sample preparation are not part of this document. It also notes that some of the analytical methods listed in Clause 5 give their own instructions when relevant. For users, this means the sample must already be taken and prepared according to the applicable companion method before the determination step.

Regulatory use

Annex ZA links the standard to Regulation (EU) 2019/1009. For products and analytes in scope, that annex shows where compliance evidence is intended to support conformity work for EU fertilising products.

What terms does oSIST prEN 17777:2026 define?

oSIST prEN 17777:2026 uses the terms and definitions from prEN 12944-1:2026 and prEN 12944-2:2026.

• Organic fertilizers - fertilizers based on organic material, used here as one of the product groups covered by the standard.
• Organo-mineral fertilizers - fertilizers combining organic and mineral components, covered as a separate product group in the scope.
• Product function category (PFC) - a category used in Regulation (EU) 2019/1009 to classify EU fertilising products; the introduction identifies PFC 1(A) and PFC 1(B).
• Water-soluble - an analyte fraction measured after water extraction, used for several nutrients in Clause 5.
• Inorganic arsenic - the non-organic arsenic fraction, measured by its own referenced method.
• Aqua regia - the digestion route referenced for total-element determinations before instrumental measurement.
• ICP-AES - inductively coupled plasma atomic emission spectrometry, the technique named in the companion methods for multi-element determination.

Who uses oSIST prEN 17777:2026?

oSIST prEN 17777:2026 is used by testing laboratories, fertilizer manufacturers, and conformity-assessment bodies. Quality managers and buyers use it to choose the right analytical route for routine control, batch release, specification checking, and regulatory evidence.

It is also relevant to organizations working with organic fertilizers, organo-mineral fertilizers, and fertilizing product blends when the referenced method scope extends to those blends.

What changed in oSIST prEN 17777:2026 from the previous edition?

oSIST prEN 17777:2026 supersedes CEN/TS 17777:2022.

• The CEN Technical Specification has been adopted as a European Standard, including the addition of Annex ZA.
• Clause 1 has been updated, with clarification on fertilizing product blends.

Which standards are used with oSIST prEN 17777:2026?

• prEN 12944-1:2026 - vocabulary for general terms.
• prEN 12944-2:2026 - vocabulary for fertilizer terms.
• prEN 17766:2025 - water extraction for subsequent determination of elements.
• prEN 17767:2026 - extraction of phosphorus by formic acid.
• prEN 17768:2026 - aqua regia digestion for subsequent determination of elements.
• prEN 17769:2026 - determination of mercury content.
• prEN 17770:2026 - ICP-AES determination of total specific elements after aqua regia digestion.
• prEN 17774:2026 - ICP-AES determination of specific elements after extraction by water and weak solvents.
• prEN 17775:2026 - determination of inorganic arsenic.
• prEN 17779:2026 - extraction of phosphorus soluble in a neutral ammonium citrate solution.

What does the oSIST prEN 17777:2026 document contain?

oSIST prEN 17777:2026 is a reference map for analytical work rather than a full test procedure document. Clause 5 lists 34 determinations and points to the companion methods needed for each one, including total, water-soluble, and reagent-soluble forms.

Annex ZA provides the linkage to Regulation (EU) 2019/1009 and the essential requirements it is intended to support. The bibliography identifies the regulation behind that linkage.

SLOVENSKI STANDARD
01-marec-2026
Organska in organsko-mineralna gnojila - Določanje specifičnih elementov
Organic and organo-mineral fertilizers - Determination of specific elements
Organische und organisch-mineralische Düngemittel - Bestimmung spezifischer
Elemente
Engrais organiques et organo-minéraux - Dosage des éléments spécifiques
Ta slovenski standard je istoveten z: prEN 17777
ICS:
65.080 Gnojila Fertilizers
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
prEN 17777
NORME EUROPÉENNE
EUROPÄISCHE NORM
February 2026
ICS 65.080 Will supersede CEN/TS 17777:2022
English Version
Organic and organo-mineral fertilizers - Determination of
specific elements
Engrais organiques et organo-minéraux - Dosage des Organische und organisch-mineralische Düngemittel -
éléments spécifiques Bestimmung spezifischer Elemente
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 260.
If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations
which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC
Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 17777:2026 E
worldwide for CEN national Members.

prEN 17777:2026 (E)
Contents Page
European foreword . 4
Introduction . 5
1 Scope . 6
2 Normative references . 7
3 Terms and definitions . 8
4 Sampling and sample preparation . 8
5 Determination of specific elements . 8
5.1 Total phosphorus content. 8
5.2 Total potassium content . 8
5.3 Total calcium content . 8
5.4 Total magnesium content . 8
5.5 Total sodium content . 8
5.6 Total sulphur content . 8
5.7 Inorganic arsenic content . 8
5.8 Cadmium content . 8
5.9 Total chromium content . 9
5.10 Total mercury content . 9
5.11 Total nickel content . 9
5.12 Total lead content . 9
5.13 Total copper content . 9
5.14 Total zinc content . 9
5.15 Water-soluble calcium content . 9
5.16 Water-soluble magnesium content . 9
5.17 Water-soluble sodium content . 9
5.18 Water-soluble sulphur content . 9
5.19 Water-soluble phosphorus content . 9
5.20 Water-soluble potassium content . 9
5.21 Neutral ammonium citrate soluble phosphorus content . 9
5.22 Formic acid soluble phosphorus content . 10
5.23 Total boron content . 10
5.24 Total cobalt content . 10
5.25 Total iron content . 10
5.26 Total manganese content . 10
5.27 Total molybdenum content . 10
5.28 Water-soluble boron content . 10
5.29 Water-soluble cobalt content . 10
5.30 Water-soluble copper content . 10
5.31 Water-soluble iron content . 10
5.32 Water-soluble manganese content . 10
5.33 Water-soluble molybdenum content . 10
5.34 Water-soluble zinc content . 10
prEN 17777:2026 (E)
Annex ZA (informative) Relationship between this European Standard and the essential
requirements of Regulation (EU) 2019/1009 making available on the market of EU
fertilising products aimed to be covered . 11
Bibliography . 18

prEN 17777:2026 (E)
European foreword
This document (prEN 17777:2026) has been prepared by Technical Committee CEN/TC 260 “Fertilizers
and liming materials”, the secretariat of which is held by DIN.
This document is currently submitted to the CEN Enquiry.
This document will supersede CEN/TS 17777:2022.
Compared to the previous edition, prEN 17777:2026 includes the following significant technical changes:
— the CEN Technical Specification has been adopted as a European Standard including the addition of
Annex ZA;
— Scope (Clause 1) updated including a clarification on fertilizing product blends.
This document has been prepared under a standardization request addressed to CEN by the European
Commission. The Standing Committee of the EFTA States subsequently approves these requests for its
Member States.
For the relationship with EU Legislation, see informative Annex ZA, which is an integral part of this
document.
prEN 17777:2026 (E)
Introduction
Regulation (EU) 2019/1009 [1] lays down the rules on the making available on the market of EU
fertilizing products and the specific safety and quality requirements for the defined product function
categories (PFCs). Organic and organo-mineral have been classified as PFC 1 (A) and PFC 1 (B)
In order to measure the compliance with the related requirements of the Regulation (EU) 2019/1009 [1]
relevant test methods have to be defined in harmonized standards. In this document the normative
references of the test methods to be used for organic and organo-mineral fertilizers are defined in order
to measure the compliance with the related requirement in the Regulation (EU) 2019/1009 [1].

prEN 17777:2026 (E)
1 Scope
This document specifies references to the methods for the determination of the following specific
elements in organic and organo-mineral fertilizers:
— determination of the total phosphorus content;
— determination of the total potassium content;
— determination of the total calcium content;
— determination of the total magnesium content;
— determination of the total sodium content;
— determination of the total sulphur content;
— determination of the inorganic arsenic content;
— determination of the cadmium content;
— determination of the total chromium content;
— determination of the total mercury content;
— determination of the total nickel content;
— determination of the total lead content;
— determination of the total copper content;
— determination of the total zinc content;
— determination of the water-soluble calcium content;
— determination of the water-soluble magnesium content;
— determination of the water-soluble sodium content;
— determination of the water-soluble sulphur content.
This document specifies references to the methods for the determination of the following specific
elements in organo-mineral fertilizers:
— determination of the water-soluble phosphorus content;
— determination of the water-soluble potassium content;
— determination of the neutral ammonium citrate soluble phosphorus content;
— determination of the formic acid soluble phosphorus content;
— determination of the total boron content;
— determination of the total cobalt content;
prEN 17777:2026 (E)
— determination of the total iron content;
— determination of the total manganese content;
— determination of the total molybdenum content;
— determination of the water-soluble boron content;
— determination of the water-soluble cobalt content;
— determination of the water-soluble copper content;
— determination of the water-soluble iron content;
— determination of the water-soluble manganese content;
— determination of the water-soluble molybdenum content;
— determination of the water-soluble zinc content.
The scope of the standards referenced in this document specifies in which cases the method is also
applicable to fertilizing product blends.
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.
prEN 12944-1:2026, Fertilizers, liming materials and inhibitors — Vocabulary — Part 1: General terms
prEN 12944-2:2026, Fertilizers, liming materials and inhibitors — Vocabulary — Part 2: Terms relating to
fertilizers
prEN 17766:2025, Organic and organo-mineral fertilizers — Extraction by water for subsequent
determination of elements
prEN 17767:2026, Organo-mineral fertilizers — Extraction of phosphorus by formic acid
prEN 17768:2026, Organic and organo-mineral fertilizers — Digestion by aqua regia for subsequent
determination of elements
prEN 17769:2026, Organic and organo-mineral fertilizers — Determination of the mercury content
prEN 17770:2026, Organic and organo-mineral fertilizers — Determination of total content of specific
elements by ICP-AES after digestion by aqua regia
prEN 17774:2026, Organic and organo-mineral fertilizers — Determination of the content of specific
elements by ICP-AES after extraction by water and weak solvents
prEN 17775:2026, Organic and organo-mineral fertilizers — Determination of the inorganic arsenic
content
prEN 17779:2026, Organo-mineral fertilizers — Extraction of phosphorus soluble in a neutral ammonium
citrate solution
prEN 17777:2026 (E)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in prEN 12944-1:2026 and
prEN 12944-2:2026 apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp/
— IEC Electropedia: available at https://www.electropedia.org/
4 Sampling and sample preparation
Sampling an
...