GB/T 20195-2024Animal feed - Preparation of test samples (English PDF)

Foreword

This document is in accordance with the provisions of GB/T 1.1-2020 "Guidelines for standardization work Part

1.Structure and drafting rules for standardization documents" Drafting. This document replaces GB/T 20195-2006 "Preparation of animal feed samples". Compared with GB/T 20195-2006, except for the structural adjustment In addition to the integration and editorial changes, the main technical changes are as follows:

a) The wording of "scope" has been changed to give the types of feed (see Chapter 1, Chapter 1 of the.2006 edition);

b) Added the terms and definitions of "batch" and "retained sample" in "sample", "parameter", "feed type" and "sample preparation procedure" (see 3.1.1, 3.1.5, 3.2, 3.3, 3.4);

c) Change "principles" to "general principles and requirements" (see Chapter 4, Chapter 4 of the.2006 edition);

d) Added "Sample Preparation Error" and "Safety Precautions" (see Chapter 5 and Chapter 6);

e) "Instruments and equipment" was changed to "equipment", and the types of equipment were increased (see Chapter 7, Chapter 5 of the.2006 edition);

f) "Sampling" has been deleted (see Chapter 6 of the.2006 edition);

g) "Step" was changed to "Procedure", and sample preparation requirements were added (see Chapter 8, Chapter 7 of the.2006 edition);

h) Added "Performance Test (Quality Control)" (see Chapter 9);

i) "Correction Factor" has been deleted (see Chapter 8 of the.2006 edition);

j) Added "Description of feed types and flow chart of sample preparation" (see Chapter 10). This document is modified to adopt ISO 6498.2012 "Guidelines for the preparation of animal feeding samples". Compared with ISO 6498.2012, this document has many structural adjustments. The comparison table of structural number changes between the two documents is shown in Appendix A. The technical differences between this document and ISO 6498.2012 and their reasons are as follows:

--- Changed the expression of "scope" and gave the feed categories, which is in line with the consistent practice of feed standard documents and is convenient for document users to understand. Interpretation and application (see Chapter 1, Chapter 1 of ISO 6498.2012);

--- Changed the definition of "batch" to more completely express the concept of "batch" related to sample preparation (see 3.1.1, ISO 6498.2012 2.1.1);

1 Scope

GB/T 20195-2024 specifies how a test sample of animal feed is prepared, and it is the standard that decides whether every subsequent analysis means anything. Feed is a heterogeneous material: a laboratory sample of a compound feed contains particles of very different size, density and composition, and the act of reducing several kilograms to the few grams that enter an analytical method is where most of the total error in a feed result is generated, not in the instrument. The standard treats that explicitly. It sets the general principles and requirements, then analyses the errors of sample preparation, the sample reduction error and the others, the minimum mass that a reduced sample must retain to remain representative, and the errors related to the technique used; then the safety precautions; then the equipment, general apparatus, drying systems, mills and dividers; and then the procedures themselves for drying, grinding, dividing, mixing and storing the prepared sample, with the requirements for samples that must not be dried or ground in the ordinary way. It takes effect on 1 April 2025.

This document describes a method for the preparation of test specimens of animal feed (including pet feed) from laboratory samples. This document applies to compound feeds, concentrated feeds, concentrate supplements, additive premixes, feed additives and feed ingredients, as well as other Preparation of samples of other types of feed. Special instructions and provisions for sample preparation required by specific analytical methods are not included in this document.

2 Normative references

This document has no normative references.

3 Terms and definitions

The following terms and definitions apply to this document.