The Development Of Discharge Air Leak Detection System In High Level Biological Safety Laboratory

In high level ( P4 level ) biological safety laboratory, there are high efficiency filters installed in the air intake and vent, to protect outdoor environment from being polluted when there are leaking of pathogenic factors in the indoor. If high efficiency filters are found leaking,the laboratory can't work,so high efficiency filters perform an important function.Nowadays, the study for leak detection of discharge air high efficiency filters in high level biological safety laboratory is very little in domestic, we completely depend on imported equipments,and can't build high level biological safety laboratory by ourselves.In the basic of the scanning inspection scheme of laser dust particles counter,which is proposed by the instrument automation equipment company of SuZhou Purification Group, I create a model machine of automatically scanning and detecting discharge air high efficiency filters. Firstly create a workbench,in the basic of it,PC as upper monitor,MSP430F149 as lower monitor, combinablenably control sampling head to move, at the same time, two laser dust particles counters installed in upper course and lower course of discharge air high efficiency filters work, work cycle of counters take 1s, sampling head which finishes scanning an area also takes 1s by coincidence,then the position coordinates which represent the area and the number of particles are showed in the PC,then sampling head doesn't continue to scan until leak detection finishes. In the basic of VB6.0 developing monitoring interface,workers can immediately observe move track of sampling head, the positions and the number of particles are saved in Access 2003 database and exported to Excel ,then workers can find leak position compared with standard.To enhance system reliability,there are three physical methods(communication lines) between PC and MSP430F149, when current communication interrupt,the system automatically adopts the next communication in priority order .When three communications all interrupt, the system stop communicating and scanning, so greatly enhance reliability, accuracy of scanning and detecting discharge air high efficiency filters.