IH Hubs and Microwave Ovens
Characteristics of Electromagnetic Fields (EMFs)
Electrical appliances usually include IH stoves and microwave ovens that use electric currents and electromagnetic fields (EMFs) for cooking. In an IH stove or microwave oven, the power is supplied from electrical outlets frequency of 50-Hertz (Hz) or 60-Hertz (Hz) EMF (extremely low frequency EMF or ELF-EMF).
In an IH stove, an electric current is applied to a coil to generate heat in the pot for cooking using an EMF with intermediate frequency EMF (IF-EMF) in the frequency range from 20 kilohertz (kHz)*1 to 90 kilohertz (kHz).
A microwave oven cooks by generating a high frequency EMF (microwave) with the frequency of 2.45 gigahertz (GHz)*2, which is efficient for heating up foods. Unlike IH oven when the heating and cooking of the product is from the surface to the interior, the microwave oven provides a simultaneous heating of the entire volume.
*1 20 kilohertz (kHz) = 20,000 Hertz (Hz) *2 2.45 gigahertz (GHz) = 2,450,000,000 Hertz (Hz)
Adverse Health Effects
There is no possibility of initiating adverse health effects as result of exposure to such EMFs in the common living environment; EMFs generated by an IH stove or a microwave oven used in the household mainly because they worked in controlled environment are thought to have no adverse health effects. In general, when exposed to a low frequency electromagnetic field (EMF) that is in the frequency range up to around 100 kilohertz (kHz) (used by an IH stove or another appliances), currents inside the human body could be induced. If the body is exposed to EMFs that are hundreds of times stronger than it is exposed to in the common living environment, nerve, muscle and heart activities may be hampered. A high frequency EMF of around 100 kilohertz (kHz) or higher frequency has a heating effect, resulting in a rise in body temperature. A continuous exposure to EMF with frequencies higher than 100 kHz might rise the body temperature.
According to World Health Organization (WHO), there are insufficient research data particularly on EMFs with intermediate frequency EMFs (IF-EMFs) including ones in the frequency range from 20 kilohertz (Hz) to 90 kilohertz (Hz) that are used in an IH stove; therefore, it is necessary to promote further researches.
The strength of an electromagnetic field (EMF) used in an IH stove is stipulated in the Regulations for Enforcement of the Radio Law of Japan. The strength of an EMF used in a microwave oven is stipulated in both Electrical Appliances and Material Safety Act and Regulations for Enforcement of the Radio Law of Japan.