What is ISO 1973 about?
ISO 1973 specifies a gravimetric method and a vibroscope method for the determination of the linear density of textile fibres applicable respectively to:
- Bundles of fibres
- Individual fibres
Useful data can be obtained on man-made fibres and, with less precision, on natural fibres. ISO 1973 only applies to fibres which can be kept straight and, in the case of bundles, parallel, during test preparation. ISO 1973 is properly applicable when the fibres are readily freed of crimp.
Note-
The methods in ISO 1973 are not applicable to tapered fibres.
The vibroscope method is not always applicable to hollow and flat (ribbon-like) fibres.
Who is ISO 1973 for?
ISO 1973 on the determination of linear density - gravimetric method and vibroscope method is useful for:
- Textile manufacturers
- Spun yarns manufacturers
- Weavers
Why should you use ISO 1973?
The linear density of individual fibres is one of the most important physical characteristics in terms of processability and predictability of the next-step intermediate product, such as spun-yarns and nonwovens.
ISO 1973 specifies testing methods, such as air-permeability on test specimen consisting of mass of fibres (Micronaire).
ISO 1973 describes two measurement methods to determine the mass per unit length (determination of the linear density) using either a bundle of 50 fibres, or on individual fibres. While the first method determines an average value, only, in relatively short time, the second method measures the individual fibre fineness and therefore the statistical distribution of the laboratory sample, too.
What’s changed since the last update?
BS EN ISO 1973:2021 is the third edition that cancels and replaces the second edition (ISO1973: 1995), which has been technically revised.
The main changes compared to the previous edition are as follows:
- ISO 6989 has been added as a normative reference in Clause 2 and 8.2.1
- A note specifying the tension application has been added in 3.2
- A correction factor (for measurements on stiff fibres) has been permitted in 4.3, 8.2.1 and 10.3
- Testing equipment without a scale but with a display, respectively connection to a computer system in 4.3 for linear density reading is permitted
- Reference to 5.2.2 “Forceps” (instead of 5.1.6) has been corrected
- Automatic application of a loading force instead of the use of forceps in 5.2.2 and 8.2.3 is permitted
- Formulae (A.1) to (A.8) have been corrected
- Grammar and linguistic consistency of definitions in 4.3, 8.1.3, 8.2.2, 9.2.1, A.1 and A.2 have been reviewed.