⚡ Glow-wire in fire hazard testing — design of the apparatus (4 mm NiCr wire, application force 0.95 N, thermocouple, specified layer), temperature verification, common test procedure and observation times, common to the GWEPT, GWFI and GWIT tests, PN-EN IEC 60695-2-10

Electronics and EMC PN-EN 60695-2-10

Overview

WHAT THE STANDARD COVERS. Scope from the PKN card of the 2022-07 edition, in full (our translation): "This part of EN 60695 describes the glow-wire test apparatus and a common test procedure simulating the effects of short-term thermal stresses that may be produced by heat sources such as glowing elements or overloaded resistors, in order to assess the fire hazard by simulation. The test procedure described in this document is a common procedure for small-scale tests in which a standardized electrically heated wire is used as the ignition source. It is a common part of the test procedures applied to end products, solid electrical insulating materials and other solid combustible materials. A detailed description of the individual tests is given in IEC 60695-2-11, IEC 60695-2-12 and IEC 60695-2-13. This basic safety publication focusing on safety test methods is primarily intended for use by technical committees in the preparation of standards in accordance with the principles laid down in IEC Guide 104 and ISO/IEC Guide 51. Technical committees are responsible, among other things, for making use of basic safety publications, where justified, in the preparation of their publications" (on the card without a full stop at the end). Parts 2-11, 2-12 and 2-13 are the flammability test for end products (GWEPT), the flammability index test for materials (GWFI) and the ignition temperature test for materials (GWIT) — introduction of the standard. We have three sample extracts: IEC 60695-2-10:2021 (edition 3, introduced by PN-EN IEC 60695-2-10:2022-07) up to subclause 4.4 and Figure 3a (page 14), IEC 60695-2-10:2013 (edition 2, withdrawn) up to subclause 7.3 (page 11) and a preview of edition 4 of 2026 up to Clause 2; we have corrigendum AC:2024-03 in full. The figures from subclauses 4.5–7.3 come from the 2013 edition and are marked as such.

TERMS AND APPARATUS (2021 edition, Clauses 3–4.4). Test temperature — the temperature to which the tip of the glow-wire is heated and stabilized before contact with the specimen. Times: t APP — time of application of the wire, the first 30 s of the test; t OBS — time of observation, the second 30 s; t I — time of ignition, from the start of the test (to the nearest 0.5 s) to the start of the longest persisting flame event (flaming or glowing); t E — time of extinguishing, to its end; t T = t E − t I — total duration; t R = t E − 30 s — flame time after removal of the wire (zero if t E < 30 s); t B — duration of the event while the wire tip is in contact with the specimen. Wire: nickel-chromium alloy (> 77 % Ni, 20 % ± 1 % Cr) with a diameter of 4.00 mm ± 0.07 mm before bending, loop according to Figure 1, without fine cracks at the tip (annealing helps); a new wire is annealed for a total of at least 10 h with a current of at least 120 A, without the thermocouple installed, and then the depth of the thermocouple hole is checked. The wire lies horizontally and presses on the specimen with a force of 0.95 N ± 0.10 N, also during the relative movement; penetration of the tip into and through the specimen is limited to 7 mm ± 0.5 mm; burning or glowing particles shall fall freely onto the layer under the specimen. Heating circuit (Figure 2) without a feedback maintaining the temperature; input voltage stable (± 2 %) during the test; current meter indicating the true RMS value with an accuracy of ± 2.5 % or better; connection of the wire to the studs with a contact area typically of at least 60 mm² at each end, screwed, soldered or brazed; the typical current for 960 °C is from 120 A to 150 A. The temperature is measured by a class 1 thermocouple according to IEC 60584-1, mineral-insulated, metal-sheathed, with an insulated junction and a nominal diameter of 1.0 mm, for continuous operation up to 960 °C (e.g. type K or N), in a sheath resistant to at least 1050 °C, fitted closely in a hole behind the tip of the wire; the thermocouple voltage is measured by a digital thermometer with a built-in reference junction. Corrigendum AC:2024-03 (IEC COR1:2024) added in 4.3: other temperature measuring instrumentation may be used, but in case of dispute the thermocouple method applies. Specified layer: a single layer of wrapping tissue (ISO 4046-4, from 12 g/m² to 30 g/m²) on a board at least 10 mm thick, 200 mm ± 5 mm below the point where the wire is applied.

CHAMBER, VERIFICATION AND TEST (2013 edition, subclauses 4.5–7.3). A draught-free chamber large enough that oxygen depletion does not affect the result and the specimen is at least 100 mm from any surface (at least 0.5 m³ is sufficient); ambient light falling on the specimen — not more than 20 lx; ventilation after each test. Timing device with a resolution of 0.2 s or better. Before each series the dimension A of the tip (Figure 1) is measured — the wire is replaced when it has decreased to 97.5 % of the initial value; after each test the tip is cleaned (e.g. with a wire brush) and inspected for cracks. The thermocouple is verified with a silver foil of at least 99.8 % purity, about 2 mm² in area and about 0.06 mm thick, placed on the tip: on slow heating the silver shall begin to melt when the thermometer indicates 960 °C ± 10 °C; in case of dispute this method applies. The board and tissue are stored before the test for at least 24 h at a temperature of 15 °C to 35 °C and a relative humidity of 45 % to 75 %. The specimen is mounted so that heat losses through the support are insignificant and its planar surface is vertical; the wire is applied to the centre of this surface. Before each set of tests the application force and the free movement of the carriage are checked. Before contact the temperature of the wire shall be constant within 5 K for at least 60 s, the thermocouple hole clean and the specimen shielded from radiation (at least 5.0 cm distance or a screen); the current is not changed during the test. The wire is applied for 30 s ± 1 s, moved towards and away at about 10–25 mm/s, and near contact at almost zero speed so that the impact force does not exceed 1.05 N; if the material melts away from the wire, the wire is not kept in contact.

EDITIONS AND CHANGES. Edition 3 (2021) compared with edition 2 (2013) according to the foreword: new terms for times in Clause 3, the former Annex A with the list of manufacturers deleted, Annex A on observation of ignition and flaming became normative, a new Annex C illustrates the times and gives examples of evaluation. Corrigendum COR1:2024 (in PKN AC:2024-03, approved on 7 March 2024): the sentence on other temperature measuring instruments in 4.3, a corrected reference in the note to B.3.1 ("7.2.0" to "7.2"), a new title and new Figures C.1 and C.2. Edition 4 (IEC 60695-2-10:2026 of 2026-05-08, 30 pages, stability date 2030): revised subclause 4.3 with a reference to the new normative Annex D "Use of pyrometer for glow-wire test" and Clause 3 aligned with ISO 13943:2017; it is not yet in the PKN catalogue.

STATUS (state of the cards on 30 September 2026). The card of PN-EN IEC 60695-2-10:2022-07 (English version) has no "Withdrawn" header — the standard is CURRENT: published 12-07-2022, 32 pages, price group P, Electrical Engineering Sector, KT 65 for Environmental Testing of Electrical Products, ICS 29.020 and 13.220.40, "Introduces: EN IEC 60695-2-10:2021 [IDT], IEC 60695-2-10:2021 [IDT]", "Replaces: PN-EN 60695-2-10:2013-12 - English version", additional element AC:2024-03. The card of PN-EN 60695-2-10:2013-12 (English version) — "Withdrawn and replaced by PN-EN IEC 60695-2-10:2022-07": published 11-12-2013, "Withdrawal date: 12-07-2022", 30 pages, introduced EN 60695-2-10:2013 and IEC 60695-2-10:2013, directive 2014/35/EU, replaced PN-EN 60695-2-10:2005 (Polish version). The PKN search for "PN-EN 60695-2-10" (30 September 2026): the 2022-07 edition without a label, the 2013-12, 2005 and 2002 editions — "Withdrawn and replaced by". IEC page: IEC 60695-2-10:2026, edition 4.0 of 2026-05-08 — replaces the 2021 edition.

HOW MANY LABORATORIES AND IN WHAT FORM (copy of the accreditation-scope database, data loaded up to 17 September 2026, read on 30 September 2026). All notations of number 60695-2-10: 13 records at 10 laboratories; in the current PCA documents the number stands in 12 cells of reference documents (27 notations — some laboratories give PN-EN, EN and IEC side by side in two editions). The 2022-07 edition (or IEC 60695-2-10:2021) is recorded by 6 laboratories: AB 022, AB 044, AB 067, AB 1340, AB 1552, AB 1690 (AB 067 as "PN-EN 60695-2-10:2022-07" — without the IEC element required by the designation of this edition); the withdrawn 2013 edition — AB 024 as the only one, and next to the current one AB 044, AB 067, AB 1552 and AB 1690 (the latter as "PN-EN 60695-2-10:2013"); without a year — AB 910, AB 1280, AB 1501. The "Laboratories" tab looks for notations that BEGIN with "PN-EN 60695-2-10" and will show 7 laboratories — it will not show AB 022, AB 910 and AB 1340, which write only "PN-EN IEC 60695-2-10" (under this beginning — 6); checked with the tab's query on the production server labcoda.pl on 30 September 2026: 7. Current scopes on the PCA website (read on 30 September 2026, issues from 21.08.2025 to 08.09.2026): all entries are in the issues in force and none is suspended.

ITEMS AND QUANTITIES. Electrotechnical and electronic products (AB 022, AB 024, AB 044, AB 067, AB 1501), solid electrical insulating and insulating materials (AB 024, AB 044, AB 1280, AB 1501), plastics and other non-metallic materials (AB 1340), non-metallic materials including cables and wires (AB 1552), terminal blocks (AB 1690), electric toys and articles for children (AB 910). Quantities named in the entries: occurrence of ignition or glowing (AB 1280, AB 1501), ignition temperature, flammability, burning time, spread of flame and glowing (AB 1501), time of ignition and extinguishing, flame height, ignition of the cotton pad (AB 067). The entries have no numerical ranges.

ALONGSIDE THIS STANDARD. In the same cells of reference documents there is Part 2-11 (GWEPT) — at 9 laboratories (at AB 1690 in the adjacent entry) — and Parts 2-12 (GWFI) and 2-13 (GWIT) — at 7: AB 022, AB 024, AB 044, AB 067, AB 1280, AB 1501, AB 1552. The flammability test for end products according to PN-EN IEC 60695-2-11 is described in a separate Knowledge Base entry; Parts 2-12 and 2-13 do not have an entry yet.

WHERE A SEEMINGLY CORRECT RESULT IS EASY TO GET. First — this standard alone gives no result: the evaluation criteria are in Parts 2-11, 2-12 and 2-13; citing only Part 2-10 does not say which test was performed. Second — temperature: the thermocouple is verified with silver foil (960 °C ± 10 °C), and the stability of the temperature before contact — for at least 60 s within 5 K; the standard requires a clean thermocouple hole and replacement of the wire when dimension A of the tip has decreased to 97.5 % of the initial value — without these checks the test temperature is uncertain. Third — force and penetration: force 0.95 N ± 0.10 N and a limit of 7 mm; at contact the impact force must not exceed 1.05 N (2013 edition) — moving the wire in too fast violates this limit. Fourth — times: since the 2021 edition the times t I, t E, t T, t R and t B have definitions in Clause 3 — they are counted for the longest persisting flame event, to the nearest 0.5 s — and the time of application t APP was designated t A in editions 1 and 2; the report should state according to which edition the times were counted. Fifth — edition: five laboratories record the withdrawn 2013 edition (one only that), and IEC already has edition 4 with an annex on temperature measurement with a pyrometer; in case of dispute about the temperature, according to corrigendum COR1:2024, the thermocouple method decides.

WHAT WE DO NOT GIVE. The dimensions of the loop and the tip (Figure 1), Annexes A (observation of ignition and flaming), B (verification by the heating current) and C (examples of evaluation) or the content of Clauses 5–8 in the wording of the 2021 edition — we give the figures from these subclauses from the 2013 edition; we do not know the content of Annex D of the 2026 edition.

Method principle

A nickel-chromium wire bent into a loop and heated by an electric current to the test temperature, measured by a thermocouple in the tip, is applied horizontally to the vertical surface of the specimen for 30 s with a force of 0.95 N, and then the specimen is observed for another 30 s; under the specimen lies wrapping tissue on a board, which shows whether falling burning particles can spread the fire. The standard describes the apparatus, its verification and the common procedure; the evaluation criteria are given by Parts 2-11 (end products), 2-12 and 2-13 (materials).

Applications

• Electrotechnical and electronic products, electrical insulating materials and plastics — glow-wire resistance testing in the scopes of 10 laboratories
• Terminal blocks (AB 1690), cables and wires (AB 1552), electric toys and articles for children (AB 910)

Key parameters

Standard

Standard number

PN-EN IEC 60695-2-10:2022-07 (wersja angielska; EN IEC 60695-2-10:2021, IEC 60695-2-10:2021 IDT) z poprawką PN-EN IEC 60695-2-10:2022-07/AC:2024-03

Title (PL)

Badanie zagrożenia ogniowego — Część 2-10: Metody badań oparte na stosowaniu rozżarzonego/gorącego drutu — Urządzenie do badania rozżarzonym drutem i ogólny sposób wykonywania prób

Title (EN)

Fire hazard testing — Part 2-10: Glowing/hot-wire based test methods — Glow-wire apparatus and common test procedure

Step-by-step procedure

1. Part and edition

   Indicate the test (2-11 GWEPT, 2-12 GWFI or 2-13 GWIT) and the test temperature; PN-EN IEC 60695-2-10:2022-07 with AC:2024-03 current (state of the cards on 30 September 2026).

2. Verification of the apparatus

   Dimension A of the tip (replacement at ≤ 97.5 %), cleanliness and absence of cracks; thermocouple — with silver foil 960 °C ± 10 °C; application force and carriage movement before each set of tests.

3. Preparation

   Board and tissue ≥ 24 h at 15–35 °C and 45–75 % RH; specimen mounted vertically, with insignificant heat losses; layer 200 mm ± 5 mm below the point of application.

4. Heating

   Wire to the test temperature, constant within 5 K for at least 60 s; specimen shielded from radiation; no changes of current until the end of the test.

5. Application and observation

   Contact for 30 s ± 1 s with a force of 0.95 N, penetration ≤ 7 mm; withdrawal; observation for another 30 s and recording of t I, t E and ignition of the tissue; evaluation according to Part 2-11, 2-12 or 2-13.

Required equipment and apparatus

Reagents, media and consumables

Health and safety (OHS)

• Risk of fire, burns and electric shock (heating current up to about 150 A), inhalation of smoke and toxic combustion products and toxic residues — caution of the standard; ventilation of the chamber after each test
• SUBSTANTIVE NOTE: this standard contains no evaluation criteria — the result makes sense only with Part 2-11, 2-12 or 2-13; in case of dispute about the temperature the thermocouple decides

Frequently asked questions