🧵 Tear force of a textile fabric, mainly woven fabric — the force required to propagate a previously started single tear in a trouser-shaped test specimen (strip 200 mm × 50 mm with a 100 mm cut), pulled in a constant-rate-of-extension (CRE) machine at 100 mm/min with a gauge length of 100 mm, in the warp and weft directions, determined from force peaks, PN-EN ISO 13937-2

Materials and NDT PN-EN ISO 13937-2

Overview

WHAT THE STANDARD COVERS. Scope from the PKN catalogue card of PN-EN ISO 13937-2:2002, in full (our translation of the Polish card text): “A single-tear method is described for determining the tear force of a flat textile product, mainly woven fabrics, using a test specimen formed into the shape of trouser legs. The possibility of applying the method also to products made by other techniques is indicated, noting its unsuitability for products of high anisotropy or loose structure”. We read the text of the standard in the preview of ISO 13937-2:2000 from the cover to clause 9.4 (test procedure — up to the criteria for a valid tear, page 5); we do not have Clauses 10 (calculation and expression of results) and 11 (test report) or Annexes A–D (including the normative Annex D — wide-width 200 mm specimens).

ACCORDING TO THE TEXT OF ISO 13937-2:2000 (forewords, introduction, Clauses 1–9.4). The standard was prepared by CEN/TC 248 (textiles and textile products) in collaboration with ISO/TC 38/SC 24 under the Vienna Agreement. The ISO 13937 series: Part 1 — ballistic pendulum (Elmendorf), 2 — trouser-shaped specimens (single tear), 3 — wing-shaped specimens (single tear), 4 — tongue-shaped specimens (double tear); Annex D is normative, A–C informative. Introduction: the series belongs to a group of methods for determining mechanical properties of textiles mainly with tensile testing machines; results obtained by one method should not be compared with those of another. Scope (Clause 1): single-tear method (“trouser test”); the force measured is the force required to propagate a previously started single tear when the force is applied parallel to the cut and the fabric tears in the direction of the force; mainly woven fabrics, possibly products made by other techniques, e.g. some nonwovens; generally not applicable to knitted fabrics and elastic woven fabrics; not suitable for highly anisotropic and loose fabrics in which the tear may transfer from one direction to the other; only CRE machines allowed; notes: trapezoidal method — ISO 9073-4 (nonwovens) or ISO 4674 (coated fabrics). Normative references: ISO 139 (atmospheres), ISO 7500-1 (verification of tensile testing machines), ISO 10012-1 (metrological confirmation). Definitions (Clause 3): CRE machine — one clamp stationary, the other moving at constant speed, system virtually free of deflection; gauge length — distance between the effective clamping points; tear force — force required to propagate a tear, qualified as “across warp” (warp threads are torn) or “across weft”; peak — point on the force–extension curve where the gradient changes from positive to negative; for calculation, peaks with a rise and fall of force of at least 10 % are used; trouser-shaped specimen — a rectangle with a single cut of defined length in the centre of the shorter edge. Principle (Clause 4): the legs are clamped in the jaws in a straight line and pulled in the direction of the cut; the force to continue the tear over a specified distance is recorded; the force is calculated from the peaks of the trace or electronically. Sampling (Clause 5): according to the product specification or by agreement (example — Annex A, cutting pattern — Annex B); without folds, creases, selvedges and unrepresentative areas. Apparatus (Clause 6): metrological confirmation according to ISO 10012-1; CRE machine — speed (100 ± 10) mm/min, gauge length (100 ± 1) mm, force recording, class 1 according to ISO 7500-1 (force error not exceeding ± 1 %, jaw separation ± 1 mm), with digital acquisition at least 8 readings per second; use of a class 2 machine is stated in the report; jaws — centres in the line of pull, no slippage and no cutting of the specimen, width preferably 75 mm, not less than the specimen width; die or template. Atmosphere (Clause 7): according to ISO 139. Specimens (Clause 8): from each laboratory sample two sets — along the warp and along the weft (for other products: lengthwise and crosswise), at least five specimens each; no two may contain the same threads, none closer than 150 mm to the edge; 50 mm specimen: strip (200 ± 2) mm × (50 ± 1) mm with a longitudinal cut (100 ± 1) mm from the centre of the width, end-of-tear mark (25 ± 1) mm from the uncut end; 200 mm wide specimens — by agreement, recommended where narrow ones are unsuitable and for especially tear-resistant fabrics (Annex D); a specimen with its longer side along the warp gives a tear “across weft”, along the weft — “across warp”. Procedure (Clause 9): gauge length 100 mm, speed 100 mm/min; each leg in one jaw, the cut in the jaw axis, the uncut end free, no pretension; tearing up to the mark; recording of force in newtons (and possibly jaw separation); with manual evaluation of peaks of dense fabrics, chart speed 2:1 relative to the extension rate; the test is valid if threads do not slip out of the fabric, the specimen does not slip in the jaws and the tear is completed in the direction of the force — other results are discarded; this is where the part we read ends.

STATUS (cards as of 02.10.2026). The card of PN-EN ISO 13937-2:2002 in the Polish version (published 23-12-2002, 18 pages, price group J) does not carry the heading “Wycofana” (withdrawn): Consumer Products Sector, KT 26 Textile Products, ICS 59.080.30, “Introduces: EN ISO 13937-2:2000 [IDT], ISO 13937-2:2000 [IDT]”, “Replaces: PN-P-04640:1976 – Polish version”. The PKN search for “PN-EN ISO 13937-2” (02.10.2026) shows only this edition.

HOW MANY LABORATORIES AND IN WHAT FORM (copy of the accreditation scope database, load up to 17.09.2026, read on 02.10.2026). The number 13937-2 appears in 7 records at 6 laboratories: AB 033, AB 154, AB 164 (two rows), AB 198, AB 1421, AB 1864. In the current scopes on the PCA website (read on 02.10.2026, issues from 03.12.2025 to 08.07.2026) all cite “PN-EN ISO 13937-2:2002”. No row is set in bold italics. The “Laboratories” tab searches for entries STARTING WITH “PN-EN ISO 13937-2” and shows 5 laboratories and 6 items — checked with the tab query on the labcoda.pl production server on 02.10.2026; AB 033 is not visible, because in its field the number stands after PN-EN ISO 4674-1:2017-02 (method B).

WHAT THE LABORATORIES TEST (items in the PCA scopes). Flat textile products (woven fabrics, at AB 1421 also knitted fabrics) — “tear force, single-tear method with trouser-shaped specimens”, with ranges: (0–5000) N and (0–2000) N (AB 164, two sections), (0–10 000) N (AB 198), (0–50 000) N (AB 1421), (5–3000) N (AB 1864), (2–20 000) N alongside Parts 3 and 4 and PN-EN ISO 9073-4 (AB 154); artificial leathers and footwear, haberdashery and leather-goods fabrics — “tear strength”, (0–5000) N, alongside PN-EN ISO 4674-1 and PN-EN ISO 9073-4 (AB 033). Most often alongside Part 3 of this series (AB 154, AB 164, AB 198, AB 1864), at AB 164 also Part 1 (Elmendorf), and alongside strip tensile strength and seam slippage (PN-EN ISO 13936-2).

WHERE A SEEMINGLY CORRECT RESULT IS EASY TO GET. Direction: a specimen cut along the warp gives a tear “across weft” — confusing the names swaps the results for the two directions. Procedure: the result is valid only if threads do not slip out of the fabric, the specimen does not slip in the jaws and the tear runs in the direction of the force up to the mark — results with the tear crossing over or threads slipping out must be discarded, not averaged. Product: knitted fabrics, elastic woven fabrics, highly anisotropic and loose products are not suitable for this method. Apparatus: only a CRE machine, 100 mm/min, gauge 100 mm, class 1 (class 2 must be reported), at least 8 readings per second — less frequent acquisition misses peaks. Peaks: only peaks with a rise and fall of force of at least 10 % count. Comparisons: results of Parts 1 (Elmendorf), 2, 3 and 4 are not mutually comparable.

WHAT WE DO NOT GIVE. We do not have Clause 10 (method of calculating the tear force from peaks — manual and electronic), Clause 11 (test report) or Annexes A–D (including the normative Annex D — 200 mm wide specimens) — so we do not give formulae, the number of peaks taken for the mean or a calculation example.

Method principle

A rectangular specimen cut from the centre of the shorter edge (“trousers”) is clamped by its legs in the jaws of a CRE machine and torn at 100 mm/min in the direction of the cut; the tear force in newtons is the value determined from the peaks of the recorded force curve over a specified tear length, separately for the warp and weft directions.

Applications

• Woven fabrics and flat textile products — tear force across the warp and weft, 6 laboratories
• Artificial leathers and footwear, haberdashery and leather-goods fabrics
• Some nonwovens (not knitted fabrics, elastic woven fabrics, highly anisotropic or loose products)

Key parameters

Standard

Standard number

PN-EN ISO 13937-2:2002 (wersja polska; EN ISO 13937-2:2000 IDT, ISO 13937-2:2000 IDT)

Title (PL)

Tekstylia — Metody badania rozdzierania płaskich wyrobów — Część 2: Wyznaczanie siły rozdzierania próbek roboczych w kształcie spodni (metoda pojedynczego rozdzierania)

Title (EN)

Textiles — Tear properties of fabrics — Part 2: Determination of tear force of trouser-shaped test specimens (Single tear method)

Step-by-step procedure

1. Sampling and conditioning

   Sampling according to the specification or by agreement, without selvedges and folds; atmosphere according to ISO 139. PN-EN ISO 13937-2:2002 current (cards as of 02.10.2026).

2. Cutting specimens

   At least 5 specimens along the warp and along the weft, 200 × 50 mm, cut 100 mm, mark 25 mm before the end; ≥ 150 mm from the edge, no common threads.

3. Setting up the machine

   Jaw separation 100 mm, speed 100 mm/min; legs in the jaws, cut in the axis, no pretension.

4. Tearing

   Tearing up to the mark with force recorded in newtons; checking that threads do not slip out, the specimen does not slip and the tear runs in the direction of the force — otherwise the result is discarded.

5. Result

   Tear force from the curve peaks, separately across the warp and across the weft; calculation method — Clause 10 (NOT GIVEN).

Required equipment and apparatus

Health and safety (OHS)

• Tensile testing machine — hands outside the jaw area during movement; the part of the standard we read contains no safety warnings
• SUBSTANTIVE NOTE: “across warp” means that warp threads are torn (specimen cut along the weft); results of different parts of ISO 13937 are not comparable

Frequently asked questions