The Final Thesis deals with fire at a business facility. In the paper, the system of firefighting in the Republic of Croatia is explained as well as the structure of fire protection, based on Law on Firefighting, standardization of fire interventions, and the organization of fire services and forces, in addition to the statistical data on interventions of Fire Brigade of the Town of Petrinja. In the paper, business facilities are described, and fires in agriculture, technical causes of fire occurrence, investigations of fire causes, site inspection and fire clues, especially those which are related to economic facilities are elaborated in detail. A fire at the business facility in the village of Gornja Bacuga near Petrinja is reconstructed in the paper.