How to protect buildings from smoke with individual lobby pressurization solutions

In this article, I will discuss how individual lobby pressurization solutions can help protect buildings from smoke hazards during a fire. These solutions consist of creating a positive pressure difference between the lobby and adjacent spaces, such as stairs and hallways, which serve as escape routes. This prevents smoke from leaking into the lobby and compromising the safety and visibility of the occupants. We will explain how these systems work, what their benefits and challenges are, and what are the best practices for installing and maintaining them.

What are individual lobby pressurization solutions?

Individual lobby pressurization solutions are ventilation systems that are installed in building lobbies, especially those with multiple floors or special uses, such as hospitals, hotels, or shopping malls. These systems aim to create a barrier of clean air between the lobby and escape areas, to prevent smoke from spreading in the event of a fire.

Individual vestibule pressurization systems are made up of three main elements:

• Supply Air: This is air injected into the lobby from an outside source or from a duct network. The supply air must be of adequate quality and controlled temperature to ensure occupant comfort and prevent overheating of the system.
• Pressure relief: it is the mechanism that allows excess air to be released from the vestibule when the doors are closed, to avoid pressurization that makes it difficult to open them. Pressure relief can be passive, through grilles or windows, or active, through fans or dampers.
• Air release: it is the mechanism that allows air and smoke to be evacuated from the fire zone, to reduce pressure and facilitate the entry of clean air into the lobby. Air release can be natural, through openings in the fa?ade or roof, or mechanical, through extractors or fans.

The combination of these elements creates a positive pressure difference between the vestibule and the exhaust areas, which prevents smoke from entering the vestibule. The pressure difference must be sufficient to counteract the force of the smoke, but not so high as to prevent the doors from opening or cause discomfort to the occupants. According to the EN 12101-6 standard, the recommended pressure difference is between 25 and 75 Pa.

To implement these systems, pressurization equipment can be installed, such as SODECA's BOXPDS kits, which include all the elements necessary to create and control pressurization in the lobby. Additionally, motorized dampers, such as SODECA's MFD or MFR series, can be fitted to regulate pressure relief and air release, depending on lobby conditions.

What are the benefits of individual lobby pressurization solutions?

Individual vestibule pressurization solutions have several benefits for building fire protection, including:

• They improve safety and visibility for occupants by preventing smoke from leaking into the vestibule and making evacuation or rescue difficult.
• They facilitate access for firefighters by creating a refuge and waiting area in the lobby, where they can prepare and coordinate to extinguish the fire.
• They reduce the risk of fire spread by limiting the air flow between the vestibule and the fire zone, which reduces the contribution of oxygen and fuel to the fire.
• They increase energy efficiency by reducing heat or cold losses from the building, by keeping the lobby isolated from the outside and from exhaust areas.
• They improve acoustic comfort by attenuating noise coming from outside or from exhaust areas, by creating an air barrier in the lobby.

What are the challenges of individual lobby pressurization solutions?

Individual vestibule pressurization solutions also present some challenges for design, installation, and maintenance, including:

• They require accurate calculation of air demand, pressure difference and pressure relief, based on the characteristics of the building, lobby, doors, leaks, and fire scene.
• They require automatic control and intelligent regulation, adapting to changing lobby conditions, such as door opening and closing, temperature and humidity variations, and smoke detection.
• They require coordination with other fire protection systems, such as detection and alarm, extinction, and compartmentalization, to guarantee joint and effective action in the event of an emergency.
• They require proper installation and periodic maintenance, which ensure the correct functioning and reliability of the system, as well as compliance with current regulations.

What are best practices for installing and maintaining individual lobby pressurization solutions?

To install and maintain individual vestibule pressurization solutions, the following best practices are recommended:

• Choose a system that meets the needs and characteristics of the building and lobby, considering use, occupancy, height, surface area, number and type of doors, and level of fire risk.
• Follow the specifications and recommendations of the EN 12101-6 standard, as well as other national or local standards that may be applicable, for the design, installation, and maintenance of the system.
• Use quality equipment and materials that meet safety, performance, and durability requirements, and that have the relevant certifications and approvals.
• Carry out tests and trials of the system, both in the installation and maintenance phases, to verify its correct operation and adjustment, and to detect and correct failures or anomalies.
• Document and record the system, including plans, calculations, certificates, manuals, protocols, and reports, and keep them in a safe and accessible place.

Conclusion

Individual lobby pressurization solutions are ventilation systems that can help protect buildings from smoke hazards during a fire. These systems consist of creating a positive pressure difference between the vestibule and the escape areas, to prevent smoke from leaking into the vestibule and compromising the safety and visibility of the occupants. For this, different elements are used, such as supply air, pressure relief and air release, which are combined and regulated according to the conditions in the lobby. These systems have multiple benefits, such as improving safety, facilitating access for firefighters, reducing the risk of fire spread, increasing energy efficiency, and improving acoustic comfort. However, they also present some challenges, such as requiring accurate calculation, automatic control, coordination with other systems, proper installation, and periodic maintenance. Therefore, it is recommended to follow good practices and current standards for the design, installation, and maintenance of individual lobby pressurization solutions.