A device to visually indicate the presence of electric fields in electrosurgical apparatus, without the necessity of wiring or an electrical connection to the apparatus, to visually annunciate when an electrosurgical instrument is active is disclosed. This is to alert the operating surgeon, and observing personnel, that the device is operational to mitigate the possibility of anyone inadvertently being injured. The device is comprised of an electrically insulated enclosure filled with a gas in close proximity to a surgical handpiece connected to a radio frequency current generator.