ISO 1130:1975 pdf download.Textile fibres – Some methods of sampling for testing.
No single technique of sampling can be devised that will serve in all circumstances. Sampling from a bale of cotton, for example, presents problems quite different from those encountered in sampling from a consignment of yarn packages, while sampling from a card web is again different from either.
If the fibres in the bulk have been well mixed, so that there is no variation in composition from one part to another, i.e. the individual fibres are distributed at random, the sample can without disadvantage be taken from one place anywhere in the bulk.
If the fibres in the bulk are not known to have been well mixed, so that the composition may vary from one part to another, a sample taken from any one place would not be representative of the whole bulk.
A selection of methods is therefore presented, illustrating techniques that have been found acceptable in meeting the commoner types of problem encountered in sampling for
An annex and tables are given in ISO 1130 for general guidance in determining the size of the test sample to be taken in order that the determined sample mean shall have given confidence limits.
2 GENERAL DEFINITIONS
For the purposes of ISO 1130 the fol lowing general definitions apply. Definitions particular to different types of fibres will be found in the appropriate clause.
2.1 individual: Any single fibre that might be taken for the purpose of measurement.
2.2 population: The aggregrate of Individuals that it is desired to characterize in one or more particulars (for example : fibres contained In a bale of cotton; all the constituent fibres in a set of yarn cops).
2.3 zoning: When the population to be sampled is known to vary from part to part with respect to the property to be Investigated, the individuals or groups of individuals in the population are taken at random from within the different
from the outside of the bale (the procedure may be facilitated by cutting one of the end bands round the bale).
NOTE — A lass satisfactory sample is yielded by selecting tufts from various places over the upper and lower sides of a bale.
Although this cotton is easily accessible, any laboratory sample obtained In this manner will represent at the most two layers, one on each side of the bale.
4.4 Sampling from a bulk consisting of several bales of cotton
4.4.1 General
The detailed method of sampling depends on the type of test to be carried out, the number of bales, and the likely variation between the bales.
4.4.2 Procedure
The following procedure shall be used unless the specification states otherwise.ISO-1130-1975