In recent years, Japanese has been faced with an increasingly aging society with a decreasing birth rate, which has resulted in problems such as a lack of care workers and an increasing number of elderly people living alone. In Japan, an increase in the aging society is predicted, thereby worsening the abovementioned problems. Therefore, it will become more difficult for elderly people living alone to receive care. We propose a Home Appliances Monitoring System to confirm their safety. This system employs a Hall element for detecting elderly persons when using home appliances. When a home appliance is used, an electric current passes through its power cord, and a magnetic flux is produced around the power cord. The Hall element converts the magnetic flux into a voltage. Based on the voltage, the system determines whether the home appliance was used. The proposed method can be applied to all home appliances, except specific cord.