oSIST prEN 18388:2026

• Abstract:

  This document specifies a method for the determination of the chloride content in inhibitors by ion chromatography.; This document is applicable to inhibitors and inhibiting compounds including mixtures of inhibitors and inhibiting compounds.

• Status: Not Published
• Public Enquiry End Date: 01-Oct-2026
• ICS: 65.080 - Fertilizers
• Technical Committee: KAT - Soil quality
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 22-Jul-2026
• Due Date: 09-Dec-2026
• Directive: Harmonized Standard2019/1009 - 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: prEN 18388 - Inhibitors - Determination of the chloride content by ion chromatography and conductivity detection (IC-CD)

Overview

oSIST prEN 18388:2026 - Inhibitors: Determination of Chloride Content by Ion Chromatography and Conductivity Detection (IC-CD) specifies a standardized method for determining chloride content in inhibitors and inhibiting compounds, including their mixtures. Developed within the framework of the European Committee for Standardization (CEN), this standard provides guidance for laboratories and industry stakeholders involved in the analysis of fertilizers, liming materials, and related substances. The clear methodology helps ensure consistent, accurate, and comparable measurement of chloride content, which is a critical parameter for quality control and regulatory compliance in the agrochemical sector.

Key Topics

• Chloride Content Determination: Detailed procedures for measuring chloride content by ion chromatography with conductivity detection, focusing on analytical reliability and consistency.
• Applicability: The method is relevant for a wide range of inhibitors and mixtures, supporting broad industry needs.
• Sample Preparation and Handling: Guidance on correct sample preparation, safeguarding the integrity and representativeness of the analytical results.
• Calibration and Quality Assurance: Emphasis on calibration curve creation, quality control samples, and criteria for checking analytical precision.
• Test Equipment and Reagents: Recommendations for laboratory apparatus, reagents, and chromatographic conditions to ensure method compatibility and reproducibility.
• Data Evaluation: Procedures for calculating chloride mass fraction in samples, with defined calculation formulas and validation criteria.
• Environmental and Safety Considerations: Best practices for handling and disposing of chemicals and laboratory waste, aligning with regulatory requirements.

Applications

• Fertilizer Quality Control: Enables manufacturers and laboratories to accurately measure the chloride content in fertilizer inhibitors, which is essential for product performance and compliance with regional and international regulations.
• Development and Registration: Supports R&D and product registration by providing a recognized and validated method for chloride determination in new and existing inhibitor formulations.
• Industrial and Environmental Monitoring: Facilitates monitoring of chloride levels in process streams and final products, helping to avoid excessive chloride concentrations that can affect crop health or lead to environmental concerns.
• Inter-laboratory Consistency: The standard’s validation through inter-laboratory studies provides confidence in repeatability and reproducibility, essential for cross-border trade and regulatory acceptance.
• Safety and Compliance: Assists laboratories in meeting quality standards and safety practices for sample handling, chemical processing, and waste disposal.

Related Standards

• EN 1482-2: Fertilizers, liming materials and inhibitors - Sampling and sample preparation – Part 2: General sample preparation provisions.
• EN 12944-1 and EN 12944-2: Fertilizers and liming materials - Vocabulary – General and fertilizer-specific terminology.
• EN 1482-1: Fertilizers, liming materials, and inhibitors - Sampling and sample preparation – Part 1: General sampling provisions.
• ISO 5725-3: Accuracy (trueness and precision) of measurement methods and results – Guidelines for collaborative study design and data interpretation.

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Keywords: ion chromatography, conductivity detection, chloride determination, inhibitors, fertilizer quality control, laboratory standardization, analytical methods, oSIST prEN 18388, CEN, agrochemical analysis, sample preparation, chloride content in fertilizers.

SLOVENSKI STANDARD
01-september-2026
Inhibitorji - Določanje klorida z ionsko kromatografijo in detekcijo na osnovi
prevodnosti (IC-CD)
Inhibitors - Determination of the chloride content by ion chromatography and conductivity
detection (IC-CD)
Hemmstoffe - Bestimmung des Chloridgehalts mittels Ionenchromatographie und
Leitfähigkeitsnachweis (IC-CD)
Ta slovenski standard je istoveten z: prEN 18388
ICS:
65.080 Gnojila Fertilizers
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
NORME EUROPÉENNE
EUROPÄISCHE NORM
August 2026
ICS
English Version
Inhibitors - Determination of the chloride content by ion
chromatography and conductivity detection (IC-CD)
Hemmstoffe - Bestimmung des Chloridgehalts mittels
Ionenchromatographie und Leitfähigkeitsnachweis (IC-
CD)
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 18388:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 Principle . 4
5 Reagents . 4
6 Apparatus and equipment . 5
7 Sampling and sample preparation . 5
7.1 General. 5
7.2 Chromatographic conditions . 5
7.3 Preparation of the calibration solutions calibration . 6
7.4 Preparation of the test solution and determination . 6
7.5 Quality control sample . 7
8 Calculation and expression of the results . 7
9 Environmental aspects . 7
10 Precision . 7
10.1 Quality assurance . 7
10.2 Inter-laboratory study . 7
10.3 Repeatability . 7
10.4 Reproducibility . 8
11 Test report . 8
Annex A (informative) Results of the inter-laboratory test. 9
A.1 Inter-laboratory study . 9
A.2 Statistical results for the determination of the chloride content by IC-CD . 10
Bibliography . 11

European foreword
This document (prEN 18388:2026) 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 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.
1 Scope
This document specifies a method for the determination of the chloride content in inhibitors by ion
chromatography.
This document is applicable to inhibitors and inhibiting compounds including mixtures of inhibitors and
inhibiting compounds.
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, liming materials and inhibitors - Sampling and sample preparation - Part 2: General
sample preparation provisions
EN 12944-1, Fertilizers and liming materials - Vocabulary - Part 1: General terms
EN 12944-2, Fertilizers and liming materials - 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 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 Principle
The inhibitor sample is diluted in water. The content of chloride is determined in diluted aqueous solution
by ion chromatography using a conductivity detector (IC-CD).
5 Reagents
All reagents shall be of recognized analytical grade and shall have negligible concentration of the element
to be determined if compared to the lowest concentration of that element in the sample solution.
5.1 Water, distilled or demineralized.
The electrical conductivity shall be < 0,2 mS/m (at 25 °C).
−
) = 1 000 mg/l.
5.2 Chloride standard solution, mass concentration γ(Cl
−
5.3 Quality control sample chloride, γ(Cl ) = 1,0 mg/l prepared from a certified solution or a certified
solid standard substance.
5.4 Eluent for IC-CD, as advised by the manufacturer to be used for determining chloride.
The eluent advised by the manufacturer of the instrument depends on the instrument
...