International Standard
ISO 20620:2021
Fertilizers and soil conditioners — Determination of total nitrogen by combustion
Reference number
ISO 20620:2021
Edition 1
International Standard
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ISO 20620:2021
Published (Edition 1, 2021)

ISO 20620:2021

ISO 20620:2021
CHF 42
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This document specifies a method for the determination of total nitrogen content in all nitrogen containing fertilizers by combustion method.

NOTE 1   The presence of non-nutritive sources of nitrogen (e.g. chelating agents) causes positive bias to samples being analysed for nutritive nitrogen content. The non-nutritive nitrogen content is subtracted from the total nitrogen value to determine the nutritive nitrogen content.

NOTE 2   Common internationally traded fertilizers were evaluated for total nitrogen by combustion analysis in the ring-study in this document. While the fertilizers analysed in this international ring study were mineral fertilizers, previous studies have shown that total nitrogen by combustion is suitable for use with many non-mineral, nitrogen-containing fertilizers.

General information

  •  : Published
     : 2021-09
    : International Standard published [60.60]
  •  : 1
     : 5
  • ISO/TC 134
  • RSS updates

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