Building for highest safety and security
Urbanisation has increased enormously over the last decades. In Germany, currently about 75 per cent of the population live in cities. Globally, there are more than 63 cities with a population of more than three million. For want of space, the future belongs to high-rise and highly complex structures. Tragic fire incidents have shown in the recent past that especially in such buildings, safe fire protection is important. But which are the directives for such special buildings, and what fire protection do they have to be equipped with nowadays?
The language of the forecasts is clear: Cities are the habitat of the future. In 2008, for the first time, more than 50 percent of people around the world lived in cities. Attractive jobs, efficient mobility structures, varied offerings in leisure, culture and education render life in metropolises more popular than life on the countryside. The construction industry has responded to the increasing demand for centrally located living spaces. Since the late nineteenth century, steel frame construction and the electric lift have caused buildings to rise to the sky. Even in the future, high-rise buildings will remain the best-proven means to deal with the lack of space in cities. In some countries of the world, there seems to be an unannounced competition going on among developers and architects. It is all about the question: Who will break the next height record? The age of skyscrapers and supertall towers is in full swing. But also hybrid use, such as adding extra floors of living space on flat-top roofs, make the buildings not only taller but also highly complex.
“For such special buildings, there are special fire protection directives,” says Thomas Rößler, Managing Director of D+H Deutschland GmbH. In Germany, these directives govern material testing and the details of processing products related to fire protection. For example, there is the mandate on smoke detectors passed by the Federal State Building Order a few years ago, according to which now even private living spaces must now be equipped with smoke detectors. “There are many older buildings in Germany in need of retrofitting”, says Rößler, who also has completed training as a specialist in fire protection planning. Recently, the city of Frankfurt has ordered fire protection testing of 540 high-rise buildings. The cities of Bielefeld and Recklinghausen are also having their buildings tested. In Wuppertal, a high-rise building whose façades are insulated with flammable material was completely evacuated.
Automatic fire extinguishing systems – Mandatory in Germany
The German fire protection directives vary between the federal states. However, the crucial details of the safety requirements are cast in very similar language in these directives. For example, the Bavarian directive for buildings taller than 60 metres states: “High-rise buildings must have automatic fire extinguishing systems that prevent the spread of the fire within a storey and between storeys for a sufficiently long time.” For this purpose, either sprinkler systems or standpipes are used.
No matter how dangerous fire seems to be, if a building burns, there is a much greater hazard. Nine out of ten victims of a fire do not burn, but instead die of poisoning from the fire smoke. “When there is a fire in a building, the escape routes must be cleared from smoke as soon as possible,” says Rößler. “Only this way can people escape and the fire brigade advance to the source of the fire efficiently.” He adds that three breaths of the toxic combustion gases are enough to make a person faint.
The toxic smoke must escape fast
In Germany, high-rise buildings must have a special safety staircase separated from the building in a way that cannot be penetrated by smoke. In addition, the buildings must be equipped with fire-retardant walls and smoke-proof doors that close automatically if smoke develops.
But how is it possible in the other parts of the building to extract the hot combustion gases fast and effectively from the building in case of fire? Especially if these buildings are large complexes? “For this purpose, there are intelligent smoke extraction systems that provide fresh air supply and smoke extraction within seconds by opening windows fully automatically,” says Torsten Helbig, Property Consultant at D+H Mechatronic AG. Depending on the requirements, which can vary greatly between hospitals, universities, museums and residential towers, it is possible to configure sections of a building individually using digital control systems for smoke and heat exhaust ventilation (SHEV).
In smoke extraction, a distinction is made between fire sections and extraction sections. For instance, if a building has a large atrium with an adjacent long hallway, one section with sprinkler systems may be sufficient for firefighting, but multiple systems will be necessary for smoke extraction. The smoke extraction system is configured using the Service & Configuration Suite (SCS) on the desktop or laptop computer. The installed controllers are simply connected to the computer unit using a USB stick.
Safe smoke extraction requires detailed planning
The distribution of SHEV controllers and window drives in highly complex buildings requires precise planning. According to Helbig, a decentralised smoke extraction concept is recommended for this purpose. In such a concept, multiple small SHEV control panels are distributed over the building and connected to each other by AdComNet, an SHEV bus system certified by VdS. The advantage: It does not require any massive or long drive cables to be routed through the building—the cable lengths and cross sections are reduced significantly. “Even the grandest smoke extraction scenarios can be implemented cost-effectively in this way without loss of safety and functionality,” says Helbig.
An interface to the building management system can monitor whether all connections function flawlessly. “With the new digital CPS-M SHEV control panel, we have developed a system enabling interaction with intrusion alarm systems, fire alarm systems, heating, lighting and ventilation,” says Stefan Decknatel, Vice President Sales and Innovation Management at D+H Mechatronic AG.
The CPS-M is equipped with the intelligent and standardised ACB (Advanced Communication Bus) bus system, which makes state-of-the-art communication between controllers and drives possible. State-of-the-art means, in this case, that the drives no longer only receive orders for opening and closing from the controllers but can also feed back information on their statuses, connections and positions. This bidirectional communication not only provides the user with more functions, but also makes it easier to carry out maintenance work, because it is significantly easier to read out information from the drives using the SCS software. Furthermore, the program allows for configuring individual settings for the drives. Such as differing movement prompts.
“The CPS-M has a fully modular design,” says Decknatel. According to him, the control panel is mounted on an almost cableless clip system on a TS 35 rail. “One click is enough to expand the system by another module and more functions.” The modules consist of functional and basic assemblies. This allows for replacing them or adding to them without dismantling the entire control panel. There is no more wiring between the modules, which also reduces the overall amount of wiring in the control panel itself. “Thanks to the modular structure dimensioning the control panel and expanding it later depending on the requirements of the building project and at the customer’s request is possible,” says Decknatel. According to him, the keyword here is plug-and-play. Thus, the CPS-M requires much less space than conventional control panels despite its higher performance.
The Internet of Things
Digitalisation also provides important answers to the challenges of urbanisation. Smart technology and the Internet of Things, that is, the connectivity of individual components in the building, ensure that the future complex requirements for safety, energy consumption and user behaviour in buildings can be coped with. And thus, not only the height of buildings will increase, but also their safety standards.