On the example of the professional fire brigade JANAF d.d. - Žitnjak Terminal shows the activity of the professional fire department in the economy within its basic operational function, which is the implementation of fire protection measures in process plants. The unit was established in accordance with the legal obligation to form professional units in the business of the owner of a building classified in the "Id" fire hazard category, based on Article 20, paragraph 3 of the Fire Protection Act. Professional fire department in JANAF d.d. - Žitnjak Terminal is the most trained and most expert organized operational force at the location, primarily for the implementation of fire protection measures, but also environmental protection measures, and partially occupational safety measures at the relevant categorized facility. The professional training of the members of the unit includes detailed knowledge of all harmful substances as well as the dangers present in a technologically complex process plant. This final paper analyzes the compliance of all subjects and their actions with legal regulations, the operation of the expert team on location in a permanent state of readiness for emergency intervention, as well as raising the level of security at the categorized facility, and considers room for improvement in all areas and at all levels of operational activity.