The Euroclass system was introduced to harmonise standards across the EU. It categorises products into one of seven reaction to fire classes ranging from A1 (non-combustible) down to F (the worst performing class in terms of combustibility), using a defined test or combination of tests. It also provides additional classification (typically associated with reaction to fire classes D – B) for smoke production (from s1 (little or no smoke) to s3 (substantial smoke)) and flaming droplets/particles (from d0 (none) to d2 (quite a lot)).
During its development, the European Commission’s Fire Regulators Group wanted the system to directly address the hazards in an actual fire scenario — a fire in a room. To do this, they used a room corner test (ISO 9705-1: 2016 - Room corner test for wall and ceiling lining products) as the reference point. Crucially, this test method was specifically designed to measure the burning behaviour of internal wall and ceiling lining products.
This decision has led to flaws within the Euroclass system, particularly around the Single Burning Item (SBI) test which can be used to assess the reaction to fire of products from class A1-D.