This paper presents risk assessment of damages for equipments in the building based on IEC standards and ITU-T recommendations. The study of risk assessment of damages for equipment in the building includes of 6 main topics: calculation of frequency of damages due to lightning discharges calculation of risk of damage calculation of risk areas estimation of probability factors consequential damage factor acceptable risk levels and mitigation methods to reduce the influence of power line induction affecting to equipment. Also the implementations of surge protective devices (SPDs) at the entrance of power lines into the building contribute to a further decrement of damage.