Accessible metal parts of class 0I appliances and class I appliances that may become live in the event of an insulation fault, shall be permanently and reliably connected to an earthing terminal within the appliance or to the earthing contact of the appliance inlet.NOTE 1 If accessible metal parts are screened from live parts by metal parts that are connected to the earthing terminal or to the earthing contact, they are not regarded as likely to become live in the event of an insulation fault.NOTE 2 Metal parts behind a decorative cover that does not withstand the test of 21.1 are considered to be accessible metal parts.Earthing terminals and earthing contacts shall not be connected to the neutral terminal.Class 0 appliances, class II appliances and class III appliances shall have no provision for earthing.Safety extra-low voltage circuits shall not be earthed unless they are protective extra-low voltage circuits.Compliance is checked by inspection.