G'day
Surely on the "less in more front" - you would say the following:-
1.Check unit, mains lead/plug and any accesories condition and integrity.
2.Perform any routine maintenance
3.Perform functional test/s
4.Perform Electrical Safety test.
5.If unit passes all 4 tests above - afix "tested OK" etc
If unit fails any of the above 4 test - fix problem/s
Can't get any more generic than that.
Phil