Multi-spectral ultrasonic gas leak detector

An ultrasonic gas leak detector is configured to discriminate the ultrasound generated by a pressurized gas leak into the atmosphere from false alarm ultrasound. An exemplary embodiment includes multiple acoustic sensors for detecting acoustic energy and providing sensor signals, including a broadband sensor and at least one narrowband sensor, and an electronic controller responsive to the sensor signals. In one exemplary embodiment, the electronic controller is configured to provide a threshold comparator function to compare a sensor signal value representative of sensed ultrasonic energy to a gas detection threshold value, and an Artificial Neural Network (ANN) function for processing signals derived from the multitude of sensor signals and applying ANN coefficients configured to discriminate false alarm sources from gas leaks. An output function generates detector outputs in dependence on the threshold comparator output and the ANN output.