Modern microwave ovens are designed with safety measures to prevent radiation leakage when they are off and unplugged. Unlike old TV sets or some older microwave models that might have had issues with radiation leakage, modern microwaves are generally safe when used according to the manufacturer's instructions.
When microwave ovens are in use, they emit non-ionizing electromagnetic radiation in the form of microwaves, which are used to heat food. These microwaves are contained within the oven's metal cavity, and the oven's door is equipped with a protective metal mesh called a Faraday cage. This mesh prevents the microwaves from escaping while still allowing you to see through the door.
When the microwave is turned off and unplugged, there should be no active generation of microwaves, and therefore, there should be no radiation leakage. However, it's worth noting that over time, the microwave's components and the protective seals may degrade or get damaged. If you suspect that your microwave is damaged or there's a significant issue with the seals, it's best to have it inspected and repaired by a qualified technician.
As for the danger of microwave radiation leakage, it's important to consider that microwaves are non-ionizing radiation, which means they lack the energy to ionize atoms or molecules, unlike ionizing radiation (e.g., X-rays or gamma rays). Non-ionizing radiation is generally considered less harmful to human health.
The current safety standards and regulations for microwave ovens set by regulatory bodies, such as the U.S. Food and Drug Administration (FDA) and the International Electrotechnical Commission (IEC), limit the allowable microwave radiation leakage to very low levels, typically 5 milliwatts per square centimeter (mW/cm²) at approximately 5 centimeters from the oven's surface. This limit is considered safe for general household use.
To put things into perspective, the typical microwave radiation leakage from a properly functioning modern microwave is usually far below the safety limits and poses minimal risk to human health. However, if you ever suspect an issue or experience any concerns about your microwave's safety, it's best to consult with a professional or consider replacing the unit. Additionally, always follow the manufacturer's instructions and safety guidelines to ensure proper usage and maintenance of your microwave oven.