AASB 136 Impairment of Assets 18-23: Recoverable amount principles: it is the higher of fair value less disposal costs and value in use, only one needs measuring if it exceeds carrying amount, value in use may stand alone where fair value cannot be reliably measured and vice versa, and recoverable amount is measured per asset unless the asset's cash inflows are not largely independent, in which case per cash-generating unit

What does 18-23 require?

Recoverable amount is the higher of two figures, fair value less disposal costs and value in use, and both need not be computed: if either one exceeds carrying amount there is no impairment. Fair value less disposal costs can often be measured without a quoted price for an identical asset, but where no reliable estimate of an orderly sale price is possible, value in use serves as recoverable amount; conversely, where there is no reason to think value in use materially exceeds fair value less disposal costs (typically an asset held for disposal, whose use cash flows are negligible), that fair value figure may be used. Recoverable amount is determined for the individual asset unless it does not generate cash inflows largely independent of other assets, in which case it is determined for the unit that contains the asset, unless the asset's fair value less disposal costs exceeds its carrying amount or its value in use can be estimated as close to that fair value figure and the figure is measurable. Reasonable approximations, averages and short-cut computations may stand in for the detailed calculations.