公开(公告)号：EP1295269A2

公开(公告)日：2003-03-26

申请号：EP01948604.2

申请日：2001-06-22

申请人： The Johns Hopkins University

发明人： NAJMI, Amir-Homayoon ,  SMITH, Dexter, G. ,  MCLOUGHLIN, Michael, P. ,  KO, Harvey, W.

IPC分类号： G08B13/16

CPC分类号： G08B13/1672

摘要： Disclosed is a method for detecting unwanted dissemination of aerosolized agents into an HVAC system in a building by detecting the sound of the dissemination at the time it occurs. To be able to distinguish the sound of the dissemination event from the ambient background noise of the HVAC system, sound extraction techniques, e.g., high pass filtering and an adaptive variance estimator, are utilized which can detect the event's noise from within the ambient background noise of the system. A microphone continually monitors background sound levels and senses the additional sound resulting from the activation of the aerosol delivery system, which has a unique sound 'signature'. Once an event is detected, defensive actions, e.g., activating additional sensors, closing all air vents, and shutting off the HVAC system, can be taken.