The appliance inlet classification is based on the maximum permissible pin temperature (cold = 70°C, warm = 120°C, or hot = 155°C). This pin temperature is measured at the base of the pin. In addition to the ambient temperature, the temperature of the pin is also influenced by the temperature reached when in the appliance is in use.
However, the temperature of the pin is by no means always the limiting factor. The limiting element is almost always the insulating material of the housing of the connector.