Stack effect of smoke for an old-style apartment in Taiwan

Many existing apartments in Taiwan allow parking of motorcycles on the 1st floor along the arcade. For the purposes of lighting and ventilation, there is an opening in upper of the gates. Taking motorcycle arson as a fire scenario, this study proved that smoke would move into the building quickly via the opening and flow upward through the staircases, posing a serious risk whenever motorcycle arson was committed. The simulation results from FDS demonstrated that the visibility decline is very fast inside staircase. When the opening was moved to the bottom of the gate, the decline became slow because the stack effect phenomenon was effectively diminished. Image-recording and laser smoke layer measurement equipment was used to measure smoke diffusion, referring to the Australian Standard, AS 4391-1999 “Smoke management systems-Hot smoke test”. The experiments were executed in a five-story building by recording visibility at a height of 1.8 m on each floor. The results indicated the same conclusions when the opening was moved to the bottom of the gate. The results also verified that the door in the attic staircase was open; the stack effect was very significant.

► Most of gates in old apartments be established top openings in Taiwan.
► The openings became smoke paths to access the buildings in a fire.
► The staircase was filled with smoke in a short time due to stack effect.
► The smoke diffusion is improved when the opening moved to the bottom of gates.
► Motorcycles should be prohibited from parking in front of gates.