The positive pressure system of the staircase is implemented in order to raise the air pressure inside the stairwell. The purpose of using this system is to create a safe and smoke-free environment for residents to escape during a fire, and its implementation is mandatory in buildings that require a positive pressure system according to architectural safety guidelines.
Smoke tends to enter the vertical shafts of the building due to the effect of the chimney and from there it spreads quickly in the building. Positive pressure systems use mechanical fans to create positive pressure in the atrium and thus control smoke. Applying a pressure difference on both sides of an obstacle can control the movement of smoke. The method of pressurization or positive pressure is that by injecting air and creating positive pressure on one side of the obstacles, high-speed air flow is created in the seams of the obstacle and smoke is not allowed to pass. In this way, the smoke movement is controlled and its spread to the positive pressure section is prevented.
The calculations of the positive pressure system should be done based on creating the appropriate pressure difference in the stairwell compared to the adjacent space. These systems can be analyzed using algebraic relations and network models such as Quantum software.