A discussion is provided of the use of ultrasonic detection of arcing, tracking, and corona in enclosed electrical cabinets to improve safety. OSHA spells out standards for arc flash assessment, various sorts of personnel protective equipment, working around energized equipment, and opening enclosed equipment in the National Fire Protection Association NFPA 70E Standard for Electrical Safety Requirements for Employee Workplaces, 2000 edition. Electric condition monitoring is used to detect arcing, tracking, and corona before flashover occurs or before an arc flash is produced when the cabinet is opened. Ultrasonic sensors can detect the airborne and structure-borne ultrasonic emissions to increase safety. The devices have a sensing range of 20kHz-100kHz, and they use heterodyning to translate ultrasonic emissions into the audible range. The portable instruments provide information through headphones for the audio signal and also on a meter that shows intensity readings. Two sensing heads that have piezoelectric transducers are also generally built in to act as a scanning module for airborne sounds and a contact probe/waveguide for structure-borne signals. A waveguide is passed around the cabinet wall to detect air paths if no sound qualities can be detected. Monitoring with a cabinet monitor installed inside the cabinet is also required for those times when no one is present.