Table 4 in the standard gives the following ES1 limits: dc 60V ac up to 1kHz 30Vrms 42.4Vpk ac 1kHz to 100kHz 30Vrms + 0.4 f ac above 100kHz 70Vrms
for ES2 the limits are: dc 120V ac up to 1kHz 50Vrms 70.7 pk ac 1kHz to 100kHz 50Vrms + 0.9 f ac above 100kHz 140Vrms
For ordinary persons, the following shall not be accessible: – bare parts at ES2, except for the pins of connectors. However, such pins shall not be accessible under normal operating conditions by the blunt probe of Figure V.3
For audio signals, table E.1 applies: When classifying audio signals (see Table E.1), the equipment shall be operated to deliver maximum non-clipped output power into its rated load impedance. The load is removed and the electrical energy source class is determined from the resulting open-circuit output voltage. For ordinary (uninstructed) persons ES1: 0-70Vrms No safeguard necessary ES2: 71-120Vrms Insulated terminals marked with ISO7000 exclamation mark in triangle or instructional safeguard for uninsulated parts of terminals and bare wiring indicating that touching uninsulated terminals or wiring may result in an unpleasant sensation.
At even higher voltages (ES3) there are more stringent insulation requirements.
Just to be clear about what devices this standard applies to: This part of IEC 62368 is applicable to the safety of electrical and electronic equipment within the field of audio, video, information and communication technology, and business and office machines with a rated voltage not exceeding 600 V.
John