References: "Surge Suppressor Fires", by Mark Goodson, IAAI Magazine - Fire & Arson Investigator, January 2000.
In February 1998, the second edition of UL 1449, Standard for Surge Protection Devices, required that surge suppressors fail in a safe manner without causing a fire. The easiest way to accomplish this was via thermal disconnectors also known as thermal cutouts or thermal fuses. Before 1998, the majority of surge suppressors did not have any thermal protection.
The requirement for GFCI has been in the NEC since 1975.
Case History: While replacing a distribution transformer, the high voltage line came in contact with the secondary of the transformer. There were nine homes connected to this transformer. All of the homes suffered some damage. At the one of the homes, the refrigerator condenser fan caught on fire. The internal damage to the surge suppression device in the Ground Fault Circuit Interrupter (GFCI) receptacle was a result of it being overloaded. More precisely, the varistor attempted to suppress the voltage surge, but the fault contained more electrical energy than the varistor could safely dissipate.
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