Skip to content

For designers

Reaction-to-fire class of a ceiling — what A2-s1,d0 means

The letter shows how much a product fuels a fire, “s” is for smoke, and “d” for whether it drips burning particles. How to read this classification — and how it relates to § 262 of the Polish Technical Building Regulations.

For designers and fire safety experts selecting a ceiling to match a building's fire protection requirements.

Every ceiling data sheet carries a code such as A2-s1,d0 or B-s2,d0. That is the reaction-to-fire class under PN-EN 13501-1: a description of how the product behaves in the early stage of a fire — whether it ignites, how quickly it releases heat, how much it smokes, and whether it drips.

That is not the same as fire resistance (REI, EI), which applies to whole building elements and states how many minutes they withstand fire. The word “fireproof” next to a ceiling tile says nothing — what counts is the class code.

How to read the class code

The code has three parts. The letter from A1 to F describes the product’s contribution to a fire: A1 — non-combustible, A2 — practically non-combustible, B — combustible but with a very limited contribution to fire, then progressively worse down to F. The “s” suffix (smoke) rates smoke production: s1 low, s2 medium, s3 high. The “d” suffix (droplets) rates burning droplets: d0 — none during the 600-second test, d1 — droplets burn no longer than 10 seconds, d2 — worse.

The Polish Technical Building Regulations do not use these symbols but plain wording instead. The table in Annex No. 3 translates one into the other.

Terms from the Polish building regulations versus classes under PN-EN 13501-1 (selection from Annex No. 3, Table 1)
Term in the regulationsReaction-to-fire classes
Non-combustibleA1; A2-s1,d0; A2-s2,d0; A2-s3,d0
Non-flammable (combustible)A2 with d1 or d2; all class B ratings (s1–s3, d0–d2)
Difficult to igniteall class C ratings; D-s1 (d0–d2)
Easily ignitableD-s2 and D-s3; E; F
Non-drippingA1 and classes with the d0 suffix (A2, B, C, D)
Heavily smokingclasses with the s3 suffix; E; F

Przewiń w poziomie, aby zobaczyć wszystkie kolumny

What § 262 requires for ceilings

Paragraph 262(1) of the Polish Technical Building Regulations states: ceiling linings and suspended ceilings must be made of materials that are non-combustible or non-flammable, non-dripping and that do not detach under fire exposure. The requirement does not apply to dwellings. Paragraph 262(2) requires the space above a suspended ceiling to be divided into compartments no larger than 1000 m², and in corridors, by barriers of non-combustible materials every 50 m.

The table shows that the condition “non-combustible or non-flammable and non-dripping” is met by classes A1, A2-…,d0 and B-…,d0. Class C no longer qualifies. In addition, § 258(2) prohibits easily ignitable materials on escape routes.

Glass-wool boards versus stretch-ceiling membranes

  • Ecophon acoustic boards, such as Master E or Super G, carry the class A2-s1,d0, and their glass-wool core is tested as non-combustible under EN ISO 1182. In the language of the Polish regulations, these are non-combustible products.

  • Stretch-ceiling membranes typically reach B-s2,d0, the best ones B-s1,d0. These are non-flammable and non-dripping products, but combustible — they should not be described as “fireproof”.

  • Where a fire-protection design requires a non-combustible product, a stretch-ceiling membrane will not pass, while an A2-s1,d0 board will. It is worth establishing this before choosing a system, not after.

Najczęściej zadawane pytania

  • Is A2-s1,d0 the same as non-combustible?

    In the sense of the Polish Technical Building Regulations, yes: Annex No. 3 classifies A2-s1,d0, alongside A1, A2-s2,d0 and A2-s3,d0, as non-combustible.

  • Can a stretch ceiling be used in an escape-route corridor?

    A membrane in class B-s1,d0 or B-s2,d0 is not easily ignitable, so § 258(2) does not rule it out. Whether it is sufficient for a specific building is decided by the design and the building’s fire-protection conditions — if they require a non-combustible product, a ceiling in class A1 or A2-…,d0 is needed.

  • How does the reaction-to-fire class differ from fire resistance?

    The reaction-to-fire class (PN-EN 13501-1) describes the product itself: whether it burns, smokes and drips. Fire resistance (e.g. EI 30) describes the element as a whole and states how many minutes it holds back fire. An ordinary suspended ceiling has a reaction-to-fire class; only systems tested as a building element have fire resistance.

Źródła

  1. Regulation on the technical conditions to be met by buildings and their location — consolidated text, Journal of Laws (Dz.U.) 2022 item 1225 (§ 258, § 262) [Polish law](otwiera się w nowej karcie)
  2. Polish Technical Building Regulations, Annex No. 3 — combustibility terms and the corresponding reaction-to-fire classes(otwiera się w nowej karcie)
  3. Measurlabs — EN 13501-1 fire classification: classes A1–F, smoke s1–s3, droplets d0–d2(otwiera się w nowej karcie)
  4. Ecophon — Master E specification text: A2-s1,d0, non-combustible core under EN ISO 1182(otwiera się w nowej karcie)
Wszystkie wpisyWięcej w tej kategorii