BC35 When it developed ED 6, the Board decided that an entity recognising exploration and evaluation assets should test those assets for impairment, and that the impairment test to be applied should be that in IAS 36 Impairment of Assets. Respondents accepted the general proposition that exploration and evaluation assets should be tested for impairment. However, the Board's proposals for a special 'cash‑generating unit for exploration and evaluation assets' (the special CGU) were not thought appropriate or useful.