Unfortunately, the following scenario is no longer absurd: terrorist attacks in cities around the world are currently feared more than ever. Important transfer sites such as metro stations pose a risk. What is to be done if poisonous smoke or gases occur in an underground tunnel system? Every human being has the deep-rooted desire to „rapidly ascend to fresh air“. In such a situation this survival instinct would, however, most likely turn out to be a fatal mistake. This is due to the fact that in the majority of the cases the intuitively used escape routes are at the same time the propagation paths for smoke or other hazardous gases.

Such kind of catastrophe can be avoided if the correct escape routes are well known in advance. Together with several partners Fraunhofer ICT-IMM has developed a measuring and analysis system which allows to understand the propagation paths of airborne hazardous substances, even in complex building structures, within the BMBF-funded project MAusKat*. Hence, security and rescue teams are able to efficiently and effectively plan escape routes and, thus, avoid such catastrophe.

Sensor platform records SF₆ and climate data

There is a wide variety of application scenarios: terrorist attacks in subway tubes or stations, at airports or other public institutions; fire incidents or accidents in industrial enterprises.  The planning of escape routes and the elaboration of rescue plans are a complex issue which depends on numerous factors.  Emerging gases behave differently according to time of the year, temperature and barometric pressure.  Under these circumstances any kind of planning is not very reasonable without having precise, reliable and continuously updated data at one’s disposal.

Whenever individual acquisition and control of data is required, ICT-IMM’s know-how comes into play. Centerpiece of the measuring and analysis system which was developed in the project MAusKat is a mobile and infrastructure independent sensor platform. In a test scenario it is possible to measure flow, propagation and concentration of a so-called tracer gas, usually SF₆, with the help of the platform via different measuring points in a building. Furthermore, climatological indicators such as temperature, humidity, barometric pressure as well as wind speed and direction are being recorded. Using a simulation it is possible to calculate propagation and concentration based on the acquired data as well as to identify danger zones and respective escape routes within a building.

As many application fields as commercially available sensors

Fraunhofer ICT-IMM can develop systems in a way, that they perfectly match the customer’s requirements while still being modular and flexible enough to be easily adapted to altered conditions.  That way, the sensor platform can be applied for instance as a leakage detector in all different application fields of SF₆. „In transformer stations SF₆ serves as cooling medium, but it is as well used for isolating high voltage power lines or in AWACS aircrafts“, says Dr. Karin Potje-Kamloth. In fact SF₆ is a colorless and odorless, nontoxic and nonflammable gas. However, it has to be considered as the strongest known greenhouse gas. „As such it shouldn’t leak in larger amounts“, explains the ICT-IMM scientist.

And this is just one application example. The open architecture of the sensor platform allows to implement any user-defined gas sensor and to evaluate the results, either manually or by means of suitable prognosis software. That is what makes Fraunhofer ICT-IMM a unique and reliable provider of development services for its customers.

*BMBF project MAusKat, 13N11677