PAT

It's a basic safety check of the mains wiring of portable appliances (anything that is portable and plugs int oth mains).
Tests that L, N and E are connected to the correct pins of the plug earth leakage and insulation.
Del

One might also:

• check the cable shows no sign of distress
• check the plug is undamaged
• do a continuity check between the earth pin of the plug and the case of the equipment, assuming that it is not double-insulated and not needing an earth
• having verified the earth connection do an insulation check between live or neutral to earth
• check that the fuse size in the plug is correct for the appliance rating and cable size (BS1363 plugs)
• check the conductor securing screws in the plug are tight
• check no conductors inside the plug show signs of distress
• check the cord grip screws bear down on the outer sheath of the cable and that it is secure
• check the plug top is secured correctly
• make a record that it has been done

Not applicable. PAT is electrical.

Follow your applicable local electrical codes and standards.

A PAT test (like surgery) is meaningless and dangerous if the person performing the test is not trained and qualified to do so and follows the applicable standards.