Tuloluokitukset

Tuloluokitukset are the fire classification system used in Finland to rate building materials, products and components according to their fire resistance and behaviour in fire. The classification is defined by national legislation, primarily the Fire Consent Act (Räätälökäytäntö) and the Finnish Standard FSS 2165, which codifies the classification methodology adopted from the European Union's construction product directive. The system groups products into six main categories, identified by numbers 0 to 5, plus a special category “UL” when the product has been certified under the internationally recognised Underwriters Laboratories system. Category 0 represents products that do not support the propagation of a fire, ensuring the highest fire safety. Category 1 indicates a very low risk; category 2, low risk; category 3, moderate risk; category 4, high risk; and category 5, very high risk. In addition to the numeric categories, a “fire resistance” rating is also given, expressed in minutes of fire exposure for which a material can maintain structural integrity and barrier function.

The classification is obtained through laboratory tests, such as the S1, S2 or I1 tests, which evaluate ignition time, flame spread, and heat release. Manufacturers of construction products must provide these results to the Finnish Building and Construction Authority (Rakennusvalvonta) and include the product’s tuloluokitus on all supplied documentation. When designing a building, architects and engineers use the tuloluokitukset of walls, floors, ceilings and other components to calculate the overall fire resistance of structural assemblies, ensuring compliance with fire safety requirements. Proper classification helps prevent the use of unsuitable materials in critical areas such as fire doors, vertical cladding, and floor partitions, thereby protecting occupants and reducing potential damage during fire incidents.