Maximum Acceptable Outage (MAO)

The Maximum Acceptable Outage marks the point beyond which the harm from a stopped process becomes unacceptable to the organisation. It exists to give recovery planning a hard boundary set by the business, not by IT. When the executive team decides which processes get expensive recovery capability and which can wait, the MAO is the number that decision rests on. Standards used in the Gulf, including NCEMA 7000 in the UAE, expect this limit to come out of the business impact analysis.

The MAO is derived in the BIA by tracing impact over time: at what point do penalties, customer loss or a regulatory breach become intolerable. The process owner proposes the value, executive management approves it, and it is fixed in the BIA report. An e-invoicing process, for example, may carry an MAO of 24 hours because after that contractual penalties and tax deadlines make the damage unacceptable; the RTO is then set at 16 hours. The rule is simple: every RTO must sit inside the MAO with a margin for failed first attempts.

The most frequent confusion is treating MAO and RTO as the same number. The MAO is a business boundary; the RTO is a management target that must be comfortably shorter, because recoveries rarely go to plan on the first try. Setting them equal removes all margin. ERGP module M3, Impact analysis and the economics of recovery, works through this distinction with numbers.