IEC Guide 117:2010(E) provides guidance for assessing the risk, to any person, of a burn from contact with hot touchable surfaces of electrotechnical equipment. Establishes surface temperature limits, where such limits are required, and describes the maximum contact periods with a hot surface that any person may be subjected to without being exposed to a risk of burn. Curves of maximum temperatures versus contact times are described for different types of material with different types of surfaces. These temperature limit values shall be taken into consideration by technical committees in determining surface temperature limits in product standards.
GSO IEC 117:2013 history
2013GSO IEC 117:2013 Electrotechnical equipment - Temperatures of touchable hot surfaces