ISO 5311:2026

International
Standard
ISO 5311
Fourth edition
Fertilizers — Determination of bulk
2026-02
density (tapped)
Engrais — Détermination de la masse volumique après tassement
Reference number
© ISO 2026
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ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Preparation of test sample . 1
5 Method 1 — Machine-tapping method . 2
5.1 Principle .2
5.2 Apparatus .2
5.3 Procedure .2
6 Method 2 — Hand-tapping method . 2
6.1 Principle .2
6.2 Apparatus .2
6.3 Procedure .3
7 Expression of results . 3
7.1 Method of calculation and formula .3
7.2 Repeatability .3
8 Test report . 3

iii
Foreword
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This document was prepared by Technical Committee ISO/TC 134, Fertilizers, soil conditioners and beneficial
substances.
This fourth edition cancels and replaces the third edition (ISO 5311:1992), of which it constitutes a minor
revision. The changes are as follows:
— the normative reference to ISO 8358 in Clause 4 was changed to ISO 14820-2.
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iv
Introduction
The bulk densities (loose and tapped) of a fertilizer provide information relative to the required size
of packaging materials, store-houses, stock-rooms, etc. Generally, the bulk density (tapped) is up t
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