Definition of halon in US English:



  • Any of a number of unreactive gaseous compounds of carbon with bromine and other halogens, used in fire extinguishers, but now known to damage the ozone layer.

    • ‘New data centers and those that undergo significant refurbishment are directed by the 1987 Montreal Protocol to use halon alternatives because of ozone-depleting properties of halon.’
    • ‘The protocol restricts the manufacture and use of human-made, ozone-depleting compounds, such as chlorofluorocarbons and halons.’
    • ‘However, halons were found to harm the ozone layer and, under the Montreal Protocol of 1987 (which the United States signed on to), developed countries were required to phase out production of those gaseous agents by 1994.’
    • ‘Oh, and halon was banned for environmental reasons, not because it smothers people.’
    • ‘The new class of clean agents is designed to provide the performance of halon without the environmental side effects.’


1960s: from halogen + -on.