A common area of confusion in the specification process when considering fire performance to meet the requirements of the Building Regulations is whether fire resistance or reaction to fire is needed, or both.  They are both vital and vitally they are different.

Reaction to fire

Reaction to fire is the measurement of a materials contribution to the development and spread of fire, generation of smoke and the production of flaming droplets. All are major factors in the rate of development of a fire and thereby the risk to people and property. With the exception of A1 (non-combustible), products have a classification with three references – for example, ‘A2-s1, d0’ . Reaction to fire is classified under BS EN 13501-1 Fire classification of construction products and building elements. Products are tested using a number of standards (most typically BS 476 Fire tests on building materials and structures in the finishes and interiors sector) depending on the required or predicted performance. The required reaction to fire classifications for materials used in commercial buildings are shown in Approved Document B.

Fire resistance

Fire resistance is a system’s ability to resist the passage of fire and excessive heat transfer from one area to another (supporting compartmentation).  In the finishes and interiors sector we typically see performance tested to BS EN 1364-1:2015 Fire resistance tests for non-loadbearing elements  Fire resistance is shown in the test report as minutes: 30, 60 etc. This refers to the ability of the whole construction to satisfy the (loadbearing capacity, integrity and insulation) referred to as REI.  Note: some products or systems may be required to be tested under load.

This information is extracted from the FIS Specifiers Guide – Ceilings and Acoustic Absorbers you can download the full version here