An Experimental Study of Smoke Movement in a Pressurised Smoke-Free Staircase

Abstract

Pressurised staircases play an important role in ensuring both safe evacuation and conditions for rescue and firefighting intervention. Occupants may be delayed in getting to safety or extinguishing the fire for unforeseen reasons. In some cases, the pressurised staircase or its lobby may serve as a temporary protected area for persons unable to escape independently, which should ensure the safety of the persons fleeing or being evacuated for a limited period of time. In such cases, the role of effective smoke control should be a priority. The purpose of pressurisation is to prevent the entry of smoke and toxic combustion gases at dangerous levels, but the possibility cannot be excluded. In the present series of studies, the smoke flow in a pressurised staircase was investigated in order to gain experience of the characteristics of smoke movement and propagation under these conditions.This involved a series of experiments with smoke cartridges placed on different staircase levels, supported by ventilation measurements to investigate the smoke flow. Based on the results of the measurements and observations, we proposed possible improvements to the technical solutions.