Definition of flashover in US English:



  • 1A high-voltage electric short circuit made through the air between exposed conductors.

    • ‘In an instant, an avalanche of electrons is rolling over the surface in a catastrophic flashover.’
    • ‘Self-cleaning, they improve line performance and reduce flashover.’
    • ‘The insulator structure may reduce the occurrence of flashovers to and from the gate lines and emitters when the field emitter device is used in a display.’
    • ‘Every single piece of steel in the Minster that will conduct electricity is now bonded with the lightning protection system to stop this sort of flashover.’
    • ‘Section 232 requires workers to wear flame resistant outerwear if they could be exposed to a flash fire or electrical equipment flashover.’
  • 2An instance of a fire spreading very rapidly across a gap because of intense heat.

    • ‘It was only a matter of time before a flashover occurred.’
    • ‘In as little as three minutes, a small fire can erupt into flashover.’
    • ‘Almost as one everyone pitched their chairs over backward, preparing for the flashover of flame that would spring from the machine, and Jon dove to the floor having already left his chair.’
    • ‘Minutes after they escaped, there was a fire flashover and the whole building went up in flames.’
    • ‘The cameras allow firefighters to find victims in smoke-filled buildings, discover hot spots that point to a fire's origin, and warn of deadly flashovers before they occur.’
    • ‘From the time a fire first breaks out to flashover, when everything catches on fire, can take as little as three minutes.’
    • ‘They were faced with the possibility of a flashover as the fire, in a matter of minutes, progressed to a stage where it was producing copious amounts of thick smoke.’
    • ‘While the fire load of the fuel was not overwhelmingly large, the flammability meant that the rate of growth of the fire was almost explosive and led to almost instantaneous flashover.’
    • ‘It had been a flashover, a kind of reaction when the room was so superheated, that it used everything in the room as fuel and the room then exploded.’
    • ‘The sudden intake of air with the heat of the cigarette caused a flashover and he was trapped as flames and smoke engulfed the vehicle.’