Engineering tool for designing a ventilation strategy for small school fires based on the comfort ventilation system

School fires are a major problem in many countries, with more than 100 fires annually only in Norwegian schools. Many of these fires are caused by arson, typically in toilet rooms and locker rooms. Such fires are often small and do not spread but can create tremendous amounts of smoke, causing significant damage beyond the room of origin. One major consequence of these school fires is the costly restoration work of the building and its ventilation system. The two main ventilation strategies in Norwegian schools are the extraction strategy (the smoke is evacuated from the fire compartment through the comfort ventilation system) and the compartmentation strategy (using fire dampers to retain the smoke inside the fire compartment). As part of a larger research project that aims to develop and document a solution for pressure and smoke control of minor fires in school buildings using the existing comfort ventilation system (including VAV/DCV dampers), an engineering tool for fire safety engineers is under development. In this paper, we present the main points of advice from the engineering tool. The results from 14 fire tests of smoke spread in a large-scale test building and a review of existing ventilation solutions and previous fire incidents in school buildings in three municipalities in Norway, which have been conducted in an earlier stage of this project, form the basis. The test building contained a corridor, one larger classroom and a small office. The fire tests were conducted using different fuel types, like an electrical scooter, gas, and a foamed rubber mattress. The engineering tool includes advice for both new, existing, and preserved buildings.