Isolation transformers, in a narrower sense, can also be called network transformers.
The network voltage is transmitted low-loss to a secondary winding. This is isolated galvanically from the primary winding by means of a so-called protective separation.
The medical isolation transformers IMEDi and IMEDe increase the protection against electric shocks for patients and staff.
Isolation transformers do not protect against an electric shock, if one touches both output terminals.