The Novelda XeThru sensor measures distance to objects with high sensitivity and accuracy. This is done by emitting very low energy impulses and measuring the time of flight. The amount of energy allowed to send is defined by regulatory agencies around the world. This application note explores the regulatory safety limits and compares the XeThru technology with other technologies. The evaluated XeThru sensor is found to emit 486 times less energy than the regulations allow and a sensor at 0.4 meters corresponds to a 5 GHz WIFI transmitter at 44 meters.