ISO
ISO 16549 Textiles — Unevenness of textile strands — Capacitance method
How much a yarn or sliver varies in mass along its length, measured by passing it through a capacitor. Reported as CV%, plus counts of thin places, thick places and neps.
- Number
- ISO 16549
- Committee
- ISO/TC 38
- Status
- active
Equivalents
| Body | Number | Equivalence | Deviation |
|---|---|---|---|
| ASTM | ASTM D1425 | NEQ | Parallel standard, not an adoption of the ISO text under ISO/IEC Guide 21. Measures the same property by a comparable method; results should not be assumed interchangeable. Confirm which standard the buyer specifies. |
Verification coverage
Checked against ASTM. Not yet checked: AATCC, BIS, SAC, JIS, EN, DIN — an absent row here does not mean no equivalent exists.
What this standard is for
Where it is used
Routine spinning quality control and yarn purchase specifications; the numbers are usually quoted against published benchmark percentiles.
Why it matters
Unevenness shows up in the fabric as streaks and barré long after the yarn has been accepted, and by then the cost is a fabric lot rather than a yarn lot. It also predicts end breakage rates in weaving.
What to watch for
Capacitance responds to mass, and to moisture with it, so readings drift with conditioning. Optical methods measure diameter instead and do not give the same figure.
Calculators that implement this
- Card Sliver Draft, Can Capacity & Change Interval
- Drawframe Draft, Doubling & Drafting-Wave Decomposition
- Positive Feeder Slippage, Loop Length Error & Barre Spacing
- Ring-Frame Drafting Zone Settings & Irregularity Floor
- Roving Bobbin Build, Doff Interval & Changeover Loss
- Roving Hank to Yarn Count Draft Predictor
- Sized Yarn Abrasion Resistance, Hairiness Gain & Add-On Adequacy
- Sliver Coil Geometry, Can Packing Density & Capacity
- Winding Production, Splice Loss & Effective Drum Efficiency
- Yarn Clearer Cut Rate, Splice Load & Clearing Efficiency
Buy the official copy from ISO
Metadata only — purchase the standard from the issuing body.
Report incorrect information on this page
Tell us what is wrong and we will check it against the source. Reports are private, are never published, and go to an editor rather than into a comment thread.