1. Introduction
Point detectors have a certain limitation in many monitor area, and standard smoke detectors are not qualified when consider the challenging environment condition and interference factors. So these applications need to use special fire detection technology, for example, aspirating smoke detectors (ASD). Driven by the new European standard EN 54-20,ASD achieved a new level in detection speed and reliability.New European standard EN 44-20 plays an important role in the application of ASD. The automatic fire detector is divided into three types: Grade A represents a very high sensitivity, Grade B represents a high sensitivity, and Grade C represents a standard sensitivity. In addition, it is worthless as the response sensitivity of detector whose sample aperture is Grand C equals to the normal point smoke detector[1]. In the past, the tests focus on the reactive state of the ADS’s evaluation device. But now, what we pay attention to are the reactive state of the whole system, including the sample line, sample aperture and sample device of ASD. ASD has been applied on some special places like large space, high building, logistics storage, and clean room.