ISO 22145:2021

Overview

ISO 22145:2021 is an international standard titled "Fertilizers and soil conditioners - Mineral soil amendments - Determination of total calcium and magnesium content." Published by the International Organization for Standardization (ISO) in 2021, this document provides a comprehensive overview of recognized analytical methods for measuring the total calcium and magnesium content in mineral soil amendments.

This standard specifically applies to mineral soil amendments that are neutral, basic, or acidic and contain calcium and/or magnesium. Its purpose is to support consistent and reliable chemical characterization of soil conditioners, which is essential for quality control, regulatory compliance, and ensuring the effectiveness of fertilizers and soil amendments.

Key Topics

• Scope and Applicability:
  ISO 22145:2021 covers mineral soil amendments containing calcium and magnesium. It serves as a guide for appropriate analytical procedures, referencing the vocabulary and definitions established in ISO 8157 for clarity and consistency.

• Analytical Methods Overview:
  The standard compiles a list of relevant, internationally recognized methods for the determination of total calcium and magnesium. These methods include gravimetric procedures, complexometric titrations, atomic absorption spectrometry (AAS), inductively coupled plasma emission techniques (ICP-OES and ICP-AES), and acid digestion protocols.

• Sample Preparation and Measurement:
  Emphasis is placed on thorough extraction methods-such as acid digestion including microwave-assisted techniques-to ensure total mineral dissolution. Measurement methods like atomic absorption and emission spectrometry provide precise quantification of calcium and magnesium concentrations in samples.

• Standardized Terminology:
  Definitions and vocabularies used in this standard correspond with ISO 8157, ensuring harmonized understanding of terms related to fertilizers and soil conditioners.

• Quality and Reliability:
  The document notes that most existing methods for total calcium and magnesium determination yield comparable results if calibration, sample preparation, and dilution steps are properly followed. This promotes reproducibility and comparability across laboratories.

Applications

ISO 22145:2021 is valuable for:

• Fertilizer Manufacturers:
  For testing and certifying calcium and magnesium contents in mineral soil amendments to meet product specifications and regulatory requirements.

• Agricultural Laboratories:
  To standardize testing procedures, ensuring accuracy and reliability in soil amendment analyses used for agronomic assessments.

• Soil Scientists and Agronomists:
  For evaluating soil conditioners' effectiveness by accurately determining their calcium and magnesium nutrient contributions.

• Environmental Testing Facilities:
  To assess mineral amendment impacts on soil chemistry and support environmental compliance monitoring.

• Regulatory Agencies:
  Establishing consistent testing frameworks to ensure fertilizer products on the market conform to defined nutrient content standards.

Related Standards

• ISO 8157:
  Vocabulary for fertilizers and soil amendments, providing key term definitions referenced throughout ISO 22145:2021.

• EPA Methods (e.g., EPA 3050 B, EPA 6010 A):
  Acid digestion and ICP measurement procedures widely used in environmental and soil testing laboratories.

• EN 12946:2000 and EN 12947:2000:
  European standards detailing complexometric and atomic absorption methods for calcium and magnesium determination in soil amendments.

• AOAC Official Methods (e.g., AOAC 917.02, AOAC 919.01):
  U.S. recognized gravimetric methods for calcium and magnesium analysis in liming materials.

• ASTM D 511 B:
  Standard method for measurement of calcium and magnesium in water using atomic absorption spectrometry, applicable in related contexts.

Keywords: ISO 22145:2021, mineral soil amendments, calcium determination, magnesium content, fertilizers, soil conditioners, analytical methods, acid digestion, atomic absorption spectrometry, ICP-OES, soil amendment testing, fertilizer quality control, soil nutrient analysis standards.