Maximum Acceptable Outage

It is the maximum duration an organisation can withstand the disruption of a business function, process, or service before its viability is at risk. It defines the critical threshold for recovery to prevent irreversible damage. Also known also as MAO, and sometime referred as Maximum Tolerable Outage (MTO), Maximum Tolerable Downtime (MTD), or Maximum Tolerable Period of Downtime (MTPD).