EP 0239817 B1 19921104 - METHOD AND DEVICE FOR PROTECTING A SPACE
Title (en)
METHOD AND DEVICE FOR PROTECTING A SPACE
Publication
Application
Priority
DE 3611184 A 19860403
Abstract (en)
[origin: US4853690A] Monitoring a room is accomplished by measurement of air pressure where air passage resistance between a secured room and an outside atmosphere is measured and an alarm actuated, if the air passage resistance drops below a predetermined value. Evaluation of typical air pressure fluctuations in a frequency range between 0.01 Hz and 10 Hz is advantageous. The air pressure resistance may be determined by difference measurements of air pressure fluctuations in the outside atmosphere and the secured room, or as a singular process wherein a connecting tube is provided between the room to be secured and the outside atmosphere, where air movements varying as a function of air pressure fluctuations are measured. Devices for the carrying out of the process are described. The devices and the process provide a simple and cost effective alarm system that operates reliably and is secure against outwitting and sabotage.
IPC 1-7
IPC 8 full level
G08B 13/20 (2006.01)
CPC (source: EP US)
G08B 13/20 (2013.01 - EP US)
Designated contracting state (EPC)
AT CH DE FR GB IT LI NL
DOCDB simple family (publication)
US 4853690 A 19890801; AT E82082 T1 19921115; DE 3611184 C1 19870903; DE 3782443 D1 19921210; EP 0239817 A2 19871007; EP 0239817 A3 19900516; EP 0239817 B1 19921104; JP H0516076 B2 19930303; JP S62237600 A 19871017
DOCDB simple family (application)
US 3261587 A 19870401; AT 87103031 T 19870304; DE 3611184 A 19860403; DE 3782443 T 19870304; EP 87103031 A 19870304; JP 8135487 A 19870403