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.

On the occasion of building fires, the risk of smoke, which adversely influences escape conditions, must be minimised. One way to reduce the risk is, for example, to pressurise the escape route in order to limit the infiltration of smoke. Careful determination of the design parameters of the pressurisation system is of great importance. This study will propose a new leakage area for single-leaf smoke control doors based on the analysis of the leakage area of the doors in the EN 12101-13 standard, estimating the leakage rate through closed doors. This value is half the currently recommended value, regardless of the opening direction. The determination of the leakage area is supported by measurements in pressurised smoke-free lobbies with single-leaf smoke control doors opening into and outwards from a pressurised space. The measurements are performed using the fans of the lobbies’ pressurisation systems to provide the required air volume. The suitability of this method has also been tested using blower door assembly measurements. The newly proposed leakage area takes into account the increased air tightness of the smoke control doors, thereby ensuring that the optimum air volume to be supplied by the pressurisation system can be determined. The results of this research suggest an appropriate leakage area value for designers when using the calculation method proposed by the applicability of the investigated standard.

The extent of smoke spread during building fires is critical, as it can adversely affect both evacuation and firefighting intervention. Smoke migration can occur through structural gaps, the potential for which should be minimised. One way to exclude smoke is to pressurise the structure, and an important starting parameter for the design of this is to know the leakage areas. The need for knowledge of the size of structural gaps has been high since the inception of design methods. This article aims to identify the potential for improving the calculation procedures by using the results of measurements on existing smoke control doors in pressurised vestibules. In this section, the author compares the results of two different measurement methods with a series of measurements in a pressurised vestibule. Using computational procedures, the air flow coefficient and leakage area of the single-leaf smoke control doors under investigation are estimated. Suggestions are made for possible improvements to the design methods.

A túlnyomásos füstmentes lépcsőházak hatékony működésének egyik legfontosabb feltétele, hogy megfelelően legyen meghatározva a légellátó rendszer kapacitása. Az ehhez szükséges bevezetendő levegőmennyiség számításához hazánkban a hő és füst elleni védelemről szóló Tűzvédelmi Műszaki Irányelv javasol műszaki megoldást. Az Országos Tűzvédelmi Szabályzatban meghatározott biztonsági szint elérhető a tűzvédelmet érintő nemzeti szabvány betartásával is, amely az MSZ EN 12101-13:2022 szabvány, illetve az abban szereplő számítási módszerek. Jelen publikációban egy meglévő túlnyomásos füstmentes lépcsőházba bevezetendő levegőmennyiség meghatározását mutatom be, figyelembe véve annak adottságait. A hazai, valamint a harmonizált szabvány számítási módszereinek alkalmazásával kapott értékeket összevetem a meglévő lépcsőház légtechnikai mérésének eredményeivel.

The extent of smoke spread during building fires is critical, as it can adversely affect both evacuation and firefighting intervention. Smoke migration can occur through structural gaps, the potential for which should be minimised. One way to exclude smoke is to pressurise the structure, and an important starting parameter for the design of this is to know the leakage areas. The need for knowledge of the size of structural gaps has been high since the inception of design methods. This article aims to identify the potential for improving the calculation procedures by using the results of measurements on existing smoke control doors in pressurised vestibules. In this section, the author presents the relevant literature on the leakage area of the openings and the air flow coefficient of the openings. It describes the measurement method for determining the air flow through doors and structures and the calculation procedure currently used.