Part of my job is to investigate fires and electrical damage. I've seen a case in a residence where a fire supposedly started in the area of an empty receptacle, and the building neutral connection was bad, resulting in all sorts of voltage fluctuations between the phases. That leads me to ask this question.
I understand that UL 498 involves testing receptacles for withstand of voltages over 1000 volts, but that this test is only for a limited number of cycles. Is there test data out there for 120 volt receptacles exposed to 240 volts for weeks at a time?