🔥 Reaction to fire of floorings and floor coverings — flame spread along a horizontal specimen under a gas-fired radiant panel, critical heat flux (CHF, HF-30) and smoke production, PN-EN ISO 9239-1

Construction PN-EN ISO 9239-1

Overview

WHAT THE STANDARD COVERS. We have a sample extract of ISO 9239-1, second edition (2002-01-15) — from the cover to clause 7.1.6 (page 6); we did not have the 2010 and 2025 editions, so the technical data below come from the 2002 edition. Scope (clause 1): a method for assessing the burning behaviour and spread of flame of horizontally mounted floorings exposed to a heat flux radiant gradient in a test chamber, when ignited with pilot flames; Annex A describes the measurement of smoke production. The method applies to all types of flooring — e.g. textile carpet, cork, wood, rubber and plastics coverings as well as coatings; the result covers the flooring together with its substrate, and a change of the backing, bonding, underlay or other elements may change it. The method must not be used alone to describe or assess the fire hazard of floorings under actual fire conditions. Introduction: the radiant flux simulates the thermal radiation levels likely to impinge on the floor of a corridor whose upper surfaces are heated by flames or hot gases during the early stage of a developing fire in an adjacent room, with wind-opposed flame spread. The specimen is placed horizontally under a gas-fired radiant panel inclined at 30°, the pilot flame is applied to the hotter end and the time taken by the flame front to reach successive distances is recorded; the result is reported as the flame spread distance versus time, the critical heat flux at extinguishment and the smoke density versus time. Foreword: the standard was prepared by CEN in collaboration with ISO/TC 92/SC 1 (Vienna Agreement); the second edition replaced ISO 9239-1:1997.

TERMS, APPARATUS AND SPECIMENS (clauses 3–7.1 of the 2002 edition). Critical heat flux at extinguishment (CHF) — the incident heat flux at the specimen surface at the point where the flame ceases to advance; HF-X — the heat flux at the farthest extent of the flame after X minutes; critical flux — CHF or HF-30, whichever is the lower value; sustained flaming — flaming lasting longer than 4 s. Chamber of calcium silicate boards (13 ± 1) mm with a density of 650 kg/m³, with a window of fire-resistant glass along the whole length of the specimen; radiant panel of porous refractory material with a surface of (300 ± 10) mm × (450 ± 10) mm, resistant up to 900 °C, fed with a gas–air mixture, inclined at (30 ± 1)°; specimen holder with an opening of (200 ± 3) mm × (1015 ± 10) mm; pilot burner on propane (0.026 ± 0.002) l/s, whose flames impinge on the specimen (10 ± 2) mm from the zero point; air velocity in the chimney (2.5 ± 0.2) m/s; pyrometer 480–530 °C; type K thermocouple; Schmidt-Boelter heat flux meter, 0–15 kW/m², ± 3 %; dummy specimen of 20 mm calcium silicate board, (850 ± 100) kg/m³, with holes every 100 mm from 110 to 910 mm. Six specimens (1050 ± 5) mm × (230 ± 5) mm — three in one direction and three perpendicular to it — on a substrate representing the actual floor according to EN 13238, with adhesive and underlay as in practice; tiles with a joint 250 mm from the zero point. Conditioning according to EN 13238, bonded floorings for at least three days. Calibration (7.1) after every significant change of the apparatus, at least once a month (with no changes — every six months): warming up for at least one hour, heat flux at the 410 mm point (5.1 ± 0.2) kW/m², then the heat flux profile from 110 to 910 mm within the tolerances of Table 1.

STATUS (state of the cards on 30 September 2026). The card of PN-EN ISO 9239-1:2026-01 (English version) has no "Withdrawn" header — the standard is CURRENT: published 13-01-2026, 44 pages, price group S, Construction and Building Structures Sector, KT 180 for Fire Safety of Buildings, ICS 13.220.40 and 97.150, "Introduces: EN ISO 9239-1:2025 [IDT], ISO 9239-1:2025 [IDT]", "Replaces: PN-EN ISO 9239-1:2010 - Polish version, PN-EN ISO 9239-1:2010 - English version"; the "Scope" field gives in Polish the whole of clause 1 (the method and the smoke assessment in Annex A, types of flooring, influence of substrate and installation, prohibition of using it alone to assess fire hazard, precision in Annex B). The card of PN-EN ISO 9239-1:2010 (Polish version, title "Badania reakcji na ogień posadzek — Część 1: Określanie właściwości ogniowych metodą płyty promieniującej") — "Withdrawn and replaced by PN-EN ISO 9239-1:2026-01": published 22-01-2013, "Withdrawal date: 13-01-2026", 30 pages, it introduced EN ISO 9239-1:2010 and ISO 9239-1:2010 [IDT] and replaced PN-EN ISO 9239-1:2004. PKN search for "PN-EN ISO 9239" (30 September 2026): the 2026-01 edition without a label, the editions 2010 (Polish and English), 2004 (Polish) and 2002 (English) — "Withdrawn and replaced by"; the query also returns PN-EN 9239 (a different standard, without the ISO element).

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 9239-1: 18 records at 10 laboratories; in the current PCA documents the number appears 20 times — six laboratories (AB 023, AB 053, AB 054, AB 1280, AB 1501, AB 1777) also list it in the table of essential characteristics "Reaction to fire" under Regulation (EU) No 305/2011; the copy contains only some of these rows, and it splits the bilingual entries of AB 053 differently from the PDF. The withdrawn 2010 edition is written by AB 029 and AB 225 as well as AB 053 (together with 2026-01 in the same entries), the new 2026-01 — by AB 053 and AB 1777 (with "EN ISO 9239-1:2025"); without a year — AB 023, AB 054, AB 304, AB 369, AB 1280 and AB 1501. The "N" mark (a method used in activities relevant to notification under Regulation 305/2011) is held by AB 023, AB 053, AB 054, AB 1280, AB 1501 and AB 1777; the asterisk (a test on the basis of which the laboratory formulates opinions and interpretations) — by AB 369. The "Laboratories" tab looks for notations that BEGIN with "PN-EN ISO 9239-1" and will show all 10 laboratories — checked with the tab's query on the production server labcoda.pl on 30 September 2026: 10. Current scopes on the PCA website (read on 30 September 2026, issues from 16.07.2025 to 01.09.2026): all entries are in the issues in force and none is suspended.

MATERIALS AND QUANTITIES. Floorings and floor coverings — 8 laboratories (at AB 053 also wooden floors, panels, parquet and indoor sports surfaces, at AB 304 — floorings used in construction and in railway rolling stock); non-metallic materials (AB 369) and construction materials and products (AB 1777). Measured quantities: critical heat flux — all; heat flux after 30 min (HF-30) — AB 054, AB 225, AB 1280, and HF-X — AB 369; smoke production — 9 laboratories, without AB 369 (at AB 304 as smoke-producing capacity, at AB 1777 as light attenuation); AB 054 also gives the flame spread distance and the time to extinguishment. The entries have no numerical ranges.

ALONGSIDE THIS STANDARD. The scopes of all 10 laboratories also include ignitability by a single flame according to PN-EN ISO 11925-2 (a separate Knowledge Base entry); six have the SBI test according to PN-EN 13823 (AB 023, AB 053, AB 054, AB 1280, AB 1501, AB 1777) and six — non-combustibility and heat of combustion according to EN ISO 1182 and EN ISO 1716 (AB 023, AB 054, AB 304, AB 1280, AB 1501, AB 1777); four — lateral spread of flame on the surface according to ISO 5658-2 (AB 304, AB 369, AB 1280, AB 1501), three — smoke density according to PN-EN ISO 5659-2 (AB 369, AB 1280, AB 1501), two — PN-EN 45545 (AB 369, AB 1501). The classification of reaction to fire on the basis of these tests is described in PN-EN 13501-1 (a separate Knowledge Base entry).

WHERE A SEEMINGLY CORRECT RESULT IS EASY TO GET. First — which flux: the critical flux is the lower of two values, CHF (the flame stopped) or HF-30 (the flux at the farthest extent after 30 min); a result given only as CHF for a flame that did not go out within 30 min is incomplete. Second — substrate and installation: the result applies to the flooring together with its substrate, adhesive and underlay; changing any of them may change it, so the report must describe them. Third — direction: the standard requires specimens in two perpendicular directions, because the material may burn differently lengthwise and crosswise. Fourth — calibration: the flux at the 410 mm point and the profile along the specimen are checked at least once a month — a result from an apparatus with a drifted profile shifts the CHF. Fifth — edition: three laboratories write the withdrawn 2010 edition, and the technical data in this entry come from the 2002 edition; whether the 2010 and 2025 editions changed the dimensions, tolerances and the way the results are determined we do not know from the sample. Sixth — hazard assessment: the result of this method is not an assessment of the fire hazard of the flooring in a real fire.

WHAT WE DO NOT GIVE. The extract of the 2002 edition ends at clause 7.1.6: we do not give the tolerances of the heat flux profile (Table 1), the course of the actual test (7.2), the expression of results (8), the test report (9), the smoke measurement (Annex A), precision (Annex B) or the gas and air installation (Annex C); we do not know the changes from the 2010 and 2025 editions.

Method principle

A flooring specimen (1050 mm × 230 mm) mounted horizontally on a substrate as in reality is placed under a gas-fired radiant panel inclined at 30°, so that the heat flux decreases along the specimen; the hotter end is ignited by the flame of a pilot burner and how far and how fast the flame travels is recorded. The critical flux is read from the heat flux profile at the point where the flame stopped (CHF) or at its farthest extent after 30 min (HF-30) — the lower of the two values; smoke is measured by light attenuation in the chimney. Numerical data according to the 2002 edition.

Applications

• Floorings and floor coverings — textile, cork, wood, rubber, plastics, coatings — in the scopes of 8 laboratories
• Wooden floors, panels, parquet and indoor sports surfaces (AB 053); floorings in railway rolling stock (AB 304); non-metallic materials and construction products (AB 369, AB 1777)
• Tests for a notified body under Regulation (EU) No 305/2011 — "N" mark at 6 laboratories

Key parameters

Standard

Standard number

PN-EN ISO 9239-1:2026-01 (wersja angielska; EN ISO 9239-1:2025, ISO 9239-1:2025 IDT)

Title (PL)

Badania reakcji na ogień dla podłóg — Część 1: Określenie zachowania podczas spalania z użyciem źródła ciepła promieniującego

Title (EN)

Reaction to fire tests for floorings — Part 1: Determination of the burning behaviour using a radiant heat source

Step-by-step procedure

1. Specimens and conditioning

   6 specimens in two perpendicular directions, on a substrate according to EN 13238, with adhesive and underlay as in practice; conditioning according to EN 13238, bonded floorings for at least 3 days.

2. Calibration

   Warm-up for at least 1 h, (5.1 ± 0.2) kW/m² at the 410 mm point, heat flux profile from 110 to 910 mm within the tolerances of Table 1 (we DO NOT GIVE the tolerances).

3. Test

   Specimen horizontal under the panel, ignition by the pilot flame at the hotter end, recording of the flame front position over time; we DO NOT GIVE the course of the test (7.2).

4. Result

   CHF or HF-30 — the lower value — from the heat flux profile; smoke according to Annex A, when required; we DO NOT GIVE the expression of results (8).

Required equipment and apparatus

Reagents, media and consumables

Health and safety (OHS)

• Risk of explosion of the gas–air mixture in the chamber — gas shut-off on failure of air or gas supply and a flame detector on the panel (introduction of the standard)
• Combustion products may be toxic — efficient extraction from the chamber and protection of the operator, e.g. gloves (introduction of the standard)
• TECHNICAL NOTE: the critical flux is the lower of CHF and HF-30; the result is not an assessment of the fire hazard of the flooring

Frequently asked questions