What is reaction to fire?
Reaction to fire testing evaluates a construction material’s contribution to fire, predominantly in the early stages of a fire starting.
This differs from Resistance to fire testing as Reaction to fire evaluates specific materials contributing to fire, whereas Resistance to fire assesses a system’s ability to resist the penetration through the system or product and prevent temperature rise between the exposed and unexposed sides in a fully developed fire situation.
How is the reaction to fire of construction materials tested?
In Europe, the classification of construction products can be determined through the Euroclass system and is classified to EN 13501 Part 1.
The Euroclass system categorises construction products into one of seven Reaction to fire classes. These classes are determined through 4 fundamental tests, EN ISO 1716, EN ISO 1182, EN ISO 11925-2 and EN 13823. These tests measure the Total Heat Release, Fire Rate Growth Index, Lateral Flame Spread as well as Smoke and Flaming Droplets.
In the UK, the National classes, covered in the relevant approved documents and standards, assess a component’s combustibility via small scale tests on small samples. The components are classified in accordance with the BS 476 suite of tests.