This part of IEC 60749 establishes a procedure for measuring the single event effects on high density integrated circuit semiconductor devices including data retention capability of semiconductor devices with memory when subjected to terrestrial cosmic rays. The single event effects sensitivity is measured while the device is irradiated in a neutron beam of known flux. This test method can be applied to any type of integrated circuit. Note 1: Semiconductor devices under high voltage stress can be subject to single event effects including SEB, single event burnout and SEGR single event gate rupture, for this subject which is not covered in this document please refer to IEC 62396-4 [10]. Note 2: In addition to the high energy neutrons some devices can have a soft error rate due to low energy (<1 eV) thermal neutrons this subject is not covered in this document refer to IEC/TS 62396-5 [11].