Fire Rating Guide

What fire rating do I need in 2020?

Fire safety is extremely important in today’s world. Existing and new commercial construction projects have to be exact with their fire ratings.

Questions about your project? Call 0330 135 5242

Classification according to European Standard EN-13501-1

DefinitionConstruction Products
Non-combustible materialsA1
A2 – s1 d0
A2 – s2 d0
A2 – s3 d0
A2 – s1 d1
A2 – s2 d1
A2 – s3 d1
A2 – s1 d2
A2 – s2 d2
A2 – s3 d2
Combustible materials: Very limited
contribution to fire
B – s1 d0
B – s2 d0
B – s3 d0
B – s1 d1
B – s2 d1
B – s3 d1
B – s1 d2
B – s2 d2
B – s3 d2
Combustible materials: Limited
contribution to fire
C – s1 d0
C – s2 d0
C – s3 d0
C – s1 d1
C – s2 d1
C – s3 d1
C – s1 d2
C – s2 d2
C – s3 d2
Combustible materials: Medium
contribution to fire
D – s1 d0
D – s2 d0
D – s3 d0
D – s1 d1
D – s2 d1
D – s3 d1
D – s1 d2
D – s2 d2
D – s3 d2
Combustible materials: Highly
contribution to fire
EE – d2
Combustible materials: Easily
flammable
F

The European classifications break down into codes, the ‘d’ part relates to ‘flaming droplets and particles’ during the first 10 minutes of exposure.

The index is:

D0 = none

D1 = some

D2 = quite a lot

The ‘s’ part relates to total smoke propagation, during the first ten minutes of exposure.

These determine a ‘smoke’ index:

S1 = a little or no smoke

S2 = quite a lot of smoke

S3 = substantial smoke

Additional ClassLevel Definition
Smoke emission during combustionS1
2
3
A little or no smoke
Quite a lot of smoke
Substantial smoke
Production of flaming droplets/particles
during combustion
D0
1
2
None
Some
Quite a lot

British Standards

As a further guide to the British standards (BS) on cladding fire testing, please see below how the older BS classifications compare to the more recent European classifications.

These were based on tests for burning materials and structures governed by BS 476.

This breaks down into two parts relevant to cladding:

Part 7 – The surface spread of flame, which measures the spread and extent that a flame would travel across the surface of the material and;

Part 6 – Fire propagation, which measures the actual contribution made by the component assembly to the growth of the fire.

British StandardTransposition to Euro Class
Non-combustibleA1
Limited CombustibilityA2–s3,d2 (or better)
Class 0B-s3,d2 (or better)
Class 1C-s3,d2 (or better)
Class 3D-s3,d2 (or better)

BS 476-6:1989+A1:2009. Fire tests on building materials and structures. Method of test for fire propagation for products.

BS 476-7:1997. Fire tests on building materials and structures. Method of test to determine the classification of the surface spread of flame of products.

Fire Safety Approved Document B. Building regulation in England covering fire safety matters within and around buildings.

Ministry of Housing, Communities and Local Government. Final Impact Assessment: Ban on combustible materials in external wall systems.

fire-resistance rating typically means the duration for which a passive fire protection system can withstand a standard fire resistance test. This can be quantified simply as a measure of time, or it may entail a host of other criteria, involving other evidence of functionality or fitness for purpose.

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