Due to the great height of many modern buildings, it is often not possible to open windows. In order to create a pleasant living and working climate, the air in such buildings is refreshed with the aid of ventilation systems. The size of such buildings means that the ventilation systems are often equipped with large air ducts where high air speeds can be reached.

The forced ventilation creates air flows in the rooms, so that early fire detection is often possible in the ventilation ducts only. The high air velocities and the fact that air from multiple rooms is carried through such channels can cause a considerable dilution of smoke in the event of a fire in a room.

The only way to detect a fire early in such cases is by means of a highly sensitive aspirating system. Stratos aspirating systems have been used very successfully for such installations for years.