A security system comprising: a controller; and a plurality of dispensing devices, wherein the controller is configured to receive signals from a plurality of remote detectors and transmit signals to the plurality of dispensing devices, the controller being adapted to determine which of the plurality of detectors has transmitted a signal and transmit a signal to a selected one or more dispensing devices to dispense a fluid based on said determination, wherein each dispensing device is configured to receive signals from the controller and dispense fluid when a signal is received.