palonkesto

Palonkesto, a Finnish term meaning fire endurance, describes the ability of a material, component, or building assembly to withstand a fire for a defined period while preserving essential functions such as structural integrity, enclosure, and insulation. The concept is central to fire safety engineering and fire protection design, and its measured performance is typically expressed as a time-based rating (for example, 30, 60 or 120 minutes) or as a combination of criteria denoted by R, E, and I in certain standards. The exact presentation depends on the applicable national and European regulations.

Fire resistance is evaluated in controlled laboratory fire tests that expose specimens to standard fire curves and assess whether they meet the required performance criteria. In the European context, standards such as EN 1363-1 for fire resistance tests and EN 13501-2 for classification of fire performance govern testing and labeling; Finland and other EU countries implement these standards within their building codes and fire safety regulations. Materials commonly assessed for palonkesto include concrete, steel with protective coatings, masonry, gypsum-based board systems, mineral wool insulations, and fire-rated door and window assemblies. The quality of installation, joints, penetrations, and continuity of protection layers strongly influence achieved palonkesto.

Applications include walls, floors and ceilings, structural frames, fire-rated doors and shutters, and enclosures around hazardous equipment. Understanding palonkesto supports compliance with legal requirements, code-prescribed safety levels, and risk management for occupants and assets.

For further information, see fire resistance rating and passive fire protection.