ability of an item to be in a state to perform a required function under given conditions at a given instant of time or over a given time interval, assuming that the required external resources are provided


  • NOTE 1 This ability depends on the combined aspects of the reliability performance, the maintainability performance and the maintenance support performance.
  • NOTE 2 Required external resources, other than maintenance resources do not affect the availability performance of the item.
  • NOTE 3 When referring to the measure for availability, the preferred term is 'instantaneous availability'.
  • NOTE 4 Adapted from IEC Multilingual Dictionary: 2001 edition.
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