Abstract: The differential pressure triggering device has a housing having first and second adjacent inner chambers with respective pressure inlets. A pressure differential responsive diaphragm extends between the inner chambers. An iron disc is positioned inside the first inner chamber and is attached to the diaphragm so as to move along a predetermined displacement course as a result of a deflection of the diaphragm. A trigger unit is mounted outside the housing alongside the first inner chamber. The trigger unit has an actuator and a switch device responsive to a motion of the actuator for producing a triggering action. A magnet is attached to the actuator in magnetic interactive mobile arrangement with the iron disc so that a displacement of the iron disc resulting from a deflection of the diaphragm, causes a corresponding displacement of the magnet, thereby driving the actuator which operates the switch device.