Four large-scale fire tests have been conducted in an apartment in one of the ‘Rabot’ towers in the city of Ghent (Belgium) at the end of September 2012. Tests 1 and 3 were carried out in a room with windows and tests 2 and 4 were carried out in a room without windows. Ventilation was present through single open doorways connecting the fire room to the living room and then to the corridor, connected to the staircase. The furniture consisted of one or two sofas and a bookcase filled with paper. The fire was ignited in the corner of a sofa by means of a lighter and six small wood cribs soaked in heptane. It was confined to the first sofa (where ignition took place) for approximately 7 to 15.5 minutes (depending on the test) before spreading to the bookshelf. The second sofa caught fire thereafter only in one test. Several sensors (