GB/T 16984-2023Raw hemp (English PDF)

Foreword

This document was issued on 6 August 2023 by the State Administration for Market Regulation; Standardization Administration of the PRC and takes effect on 1 March 2024.

It is a GB/T standard: recommended rather than compulsory, but it is the text a Chinese reviewer applies when assessing a submission.

1 Scope

GB/T 16984-2023 covers raw hemp, the bast fibre as it comes out of processing and before it is spun, and sorts it into four categories according to the technology used on it: water retted hemp, sunned hemp, hemp peeled from green straw, and dew-retting hemp. The requirements clause is built around grading, with a grading table for the categories the clause tabulates, so a lot is judged on the scale that belongs to its own processing route rather than against one common scale. Test methods, inspection rules, and packaging, marking, transportation and storage follow, with the terms the grading language depends on defined at the front. Raw bast fibre is bought and sold on grade, and the grade is what tells a spinner what the material will do; without an agreed classification and an agreed way of measuring against it, buyer and seller end up describing the same bale in different words and settling the difference by argument. Useful to hemp growers and primary processors, fibre traders, textile mills buying raw stock, and inspection bodies handling delivery disputes.

This document gives the classification of raw hemp, specifies the requirements,

inspection rules, packaging, marking, transportation and storage of raw hemp, and

describes the corresponding test methods.

This document applies to the quality grade assessment of raw hemp.

2 Normative references

The following referenced documents are indispensable for the application 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.

GB/T 6529 Textiles - Standard atmospheres for conditioning and testing

GB/T 8170 Rules of rounding off for numerical values & expression and judgement

of limiting values

GB/T 9995 Determination of moisture content and moisture regain of textile - Oven-

drying method

GB/T 12945 Jute fiber

GB/T 17345 Scutched flax

3 Terms and definitions

For the purpose of this document, the following terms and definitions apply.

3.1

raw hemp

Hemp bast used as textile raw material.

3.2

water retted hemp

Hemp bast after hemp stems are water-retted, rinsed, peeled and dried.

3.3

sunned hemp

Hemp bast peeled after hemp stems are dried, piled and exposed to the sun.

3.4

peeling hemp from green straw

Hemp bast peeled directly after hemp is harvested.

3.5

dew-retting hemp

Hemp bast made after hemp is harvested, dried in the sun, then watered by natural

rainwater, peeled and stemmed.

3.6

speck

Defects of raw hemp that affect its use in textiles due to pests, diseases, wind damage,

mildew, etc.

3.7

foreign materials content

Proportion of hemp leaves, hemp scraps, hemp roots, bast with no processing value and

other impurities in raw hemp.

4 Classification

Raw hemp is classified into four categories according to the processing technology.

water retted hemp, sunned hemp, peeling hemp from green straw, and dew-retting hemp.

5 Requirements

5.1 Grading requirements

Grading requirements for water retted hemp are shown in Table 1, grading requirements

for sunned hemp are shown in Table 2, grading requirements for peeling hemp from

green straw are shown in Table 3, and grading requirements for dew-retting hemp are

shown in Table 4.

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