A laboratory moving from woven and knitted fabrics into nonwovens often assumes it can keep its existing methods. It cannot, at least not by default. Several of the most common textile standards explicitly exclude nonwovens — ISO 5084 for thickness is one — and nonwovens have their own family of methods: ISO 9073, Nonwovens — Test methods.
The family is large, it is numbered by part, and several parts have been revised since 2021. This guide maps the main parts to what they measure and to the instrument each one needs.
The main parts at a glance
| Part | Property | Instrument type |
|---|---|---|
| ISO 9073-1 | Mass per unit area | Cutter and precision balance |
| ISO 9073-2 | Thickness | Thickness gauge with nonwoven feet and loads |
| ISO 9073-3 | Tensile strength and elongation, strip | Tensile tester (CRE) |
| ISO 9073-4 | Tear resistance, trapezoid | Tensile tester (CRE) |
| ISO 9073-5 | Resistance to mechanical penetration, ball | Ball burst tester |
| ISO 9073-6 | Absorption | Absorption apparatus |
| ISO 9073-7 | Bending length | Cantilever stiffness tester |
| ISO 9073-9 | Drapability, drape coefficient | Drape tester |
| ISO 9073-12 to -14 | Demand absorbency, repeated strike-through, wetback | Hygiene-product test rigs |
| ISO 9073-15 | Air permeability | Air permeability tester |
| ISO 9073-16 | Resistance to water penetration (hydrostatic pressure) | Hydrostatic head tester |
| ISO 9073-18 | Tensile strength, grab | Tensile tester (CRE) with grab faces |
A typical technical-nonwoven lab starts with parts 1, 2, 3 and 4. Hygiene and medical nonwovens add the liquid-handling parts; filtration and protective products add 15 and 16.
Editions have moved — check the year
Recent revisions include part 1 (2023), part 3 (2023), part 4 (2021), part 5 (2025), part 7 (2024) and part 18 (2023). Part 2 dates from much earlier. Customer specifications written years ago may reference superseded editions, and method details can change between editions.
When a specification quotes "ISO 9073-3" with no year, agree which edition applies. When it quotes an old year, decide with the customer whether to test to that edition or the current one, and state it on the report.
Where woven-fabric habits cause errors
Tensile: strip width options. ISO 9073-3 offers two procedures, with specimen widths of 25 mm (option A) and 50 mm (option B). A result without the option is ambiguous. ISO 9073-18 is the grab method; do not compare strip and grab results.
Tear: trapezoid, not Elmendorf. ISO 9073-4 uses the trapezoid procedure on a tensile tester. A lab with an Elmendorf pendulum may be tempted to use it on nonwovens, but that is a different method with a different result.
Ball burst for elastic nonwovens. ISO 9073-5 is designed primarily for nonwovens with some degree of elasticity, for which a regular burst test does not apply.
Thickness. ISO 5084 excludes nonwovens. ISO 9073-2 is the thickness method written for nonwovens. Many nonwovens are bulky and compressible, so pressure and foot area matter even more than for wovens.
Direction: MD and CD, not warp and weft
Nonwovens have no warp and weft. Their properties differ between the machine direction (MD) and the cross direction (CD), often strongly: a carded or spunlaced web is often considerably stronger in MD than in CD.
- Mark MD on every sample when it is cut from the roll; once a piece is cut, MD is often impossible to identify by eye.
- Test MD and CD separately and report them separately.
- Never average MD and CD into a single "strength" figure.
Sampling across the width
Nonwoven rolls vary across the width, especially near the edges, where web formation and bonding are less uniform. Take specimens across the usable width, away from the edges, and from more than one position along the roll. For mass per unit area this matters more than any balance choice: a light spunbond can show large differences between the centre and the edge of a roll.
Light nonwovens also need a balance fine enough for the specimen mass. A specimen of a low-weight spunbond can weigh only a fraction of a gram.
Conditioning
Nonwovens made of hydrophobic polymers such as polypropylene absorb little moisture, so labs are sometimes tempted to skip conditioning. Many nonwovens contain viscose, cotton or pulp, which do absorb moisture, and many finishes are hygroscopic. Condition as the relevant part requires, normally in the standard atmosphere of ISO 139.
Building the equipment list
For a new nonwoven lab, a practical sequence is:
- Balance and cutter for ISO 9073-1.
- Thickness gauge with feet and loads suitable for ISO 9073-2.
- Tensile tester with strip and grab jaw faces for ISO 9073-3, -4 and -18.
- Stiffness and drape for ISO 9073-7 and -9, if hand or drapability matters to customers.
- Air permeability and hydrostatic head for ISO 9073-15 and -16 for filtration, medical or protective products.
- Ball burst for ISO 9073-5 when elastic nonwovens are produced.
We manufacture the balances, thickness gauges, tensile testers, stiffness and drape testers, air permeability and hydrostatic head testers listed against these parts in our own workshop in Istanbul.