2021 New Update: How much radiation does a microwave emit?
In modern life, great inventions are created. Many people trust the microwave oven with outstanding advantages to use in the kitchen. However, there are many opinions about what kind of waves are used in microwave and how much radiation does a microwave emit ? The following article will focus on explaining this problem for you.
What is radiation?
Radiation is the invisible rays and can only be perceived by the measuring equipment. Radiation is understood as ionizing radiation, consisting of beams of microscopic particles and electromagnetic waves capable of ionizing when passing through matter, except for electromagnetic waves with wavelengths longer than 100 nm (nanometers).
Limit radiation overdose
1 Sv = 103 mSv = 106 µSv
The average natural radiation dose is from 0.001 to 0.002 Sv or 1-2 mSv / year. A single x-ray is usually subject to a dose of 0.2- 5Sv
Currently, in the legal documents on limit dose standards, the unit Sv / year, mSv / h, µSv / h is used.
As recommended by the ICRP (International Commission on Radiation Safety), workers’ maximum radiation dose limit should not exceed 50mSv / year. For pregnant women working in radiation conditions, it must not exceed two mSv / year.
The total dose of a continuous irradiation and a single dose below 1000 mSv will not cause any serious health effects.
In about 2000 mSv single dose may cause mild symptoms such as nausea, headache about 2 hours after radiation exposure. A single dose of 2000mSv reduces both white blood cells and red blood cells by 50%.
In about 3000 mSv or more, the symptoms appear fatigued, loss of appetite, fever, diarrhea. Often less risk of death, after a few weeks or months, the patient can recover.
From 4000 – 6000 mSv: Causes damage to intestinal mucosa or bone marrow. A dose of 4000 mSv is potentially life-threatening, 5000 mSv can be fatal, and 6000 mSv is almost certainly fatal without a timely emergency.
Doses of 6000 mSv or more hoping to live a few weeks is difficult. Higher doses can be fatal in the short term.
Ionizing radiation versus non-ionizing radiation
Radiation is energy that travels through the air in very small wavelengths or molecules. All forms of radiation are invisible unless there is a spectrum when visible light is present. Some forms of radiation can be felt as heat, but most radiation cannot be felt. The most dangerous form of radiation – called an “ionization”, like an X-ray – cannot be seen or felt.
There are three basic types of radiation: electromagnetic fields, sounds, and molecules. Many industrial workers are exposed to sound radiation as noise and to be exposed to electromagnetic radiation.
There are two types of electromagnetic radiation:
- “Ionizing” radiation, such as X-rays or gamma rays, enters the human body and damages cells and genes; and
- “Non-ionizing” radiation, including radiofrequency, visible light, ultraviolet light, and infrared radiation.
Non-ionizing radiation does not enter the human body but causes molecules on the body surface (skin, eyes, and testicles) to vibrate faster. These vibrations cause the cell to heat up more warm than usual. The most common health problems caused by non-ionizing radiation are skin burns and cataracts.
How does a microwave oven work?
Construction of a microwave oven
Before coming in how much radiation does a microwave give off, we need to know about the construction. A conventional oven will consist of the following main components:
- Cooking chamber (drying chamber): This unit is also known as Usable Space. This is the space in which the product needs to be cooked. This cooking chamber is composed of partitions, which reflect the microwave rays back and forth before they are absorbed into the food.
- Microcontroller circuit
- High-frequency generator: Magnetron is a high-power (microwave) transmitter, a microwave wave generated from an electronic oscillator and amplified by a magnetron acting as an electronic lamp 3 pole. Since they are the source of the microwave rays (drying agents or cooking agents), this is the most important part.
It consists of a hollow metal cylinder consisting of an anode in which resonant holes have been placed to increase the frequency from 50 Hz to 2450 Hz. For the resonant circuit, the value of the coil and the capacitor will determine the frequency. This source is usually lamps, and magnetron lamp construction can be different depending on the model.
- Waveguides: These waveguides are responsible for the direction of the wave’s motion.
- Other parts: Like some electrical circuits, transformers.
- The microwave doors are shielded by a metal mesh that acts as a microwave reflector and keeps the microwaves from leaking out. The mesh size is too small for wavelengths to escape but large enough to see what is cooking inside.
Most of the microwaves have a rotating glass table that acts as a conveyor for heat in all positions. If the food does not rotate evenly, part of the food will get stuck in the middle of the hot and cold spot in the microwave.
What is the working principle of a microwave oven?
In general, while microwave ovens can vary in shape, size, or intended use, most of them share the same basic principles of operation. The principle diagram of an ordinary microwave oven can be understood as follows:
The magnetron acts like a 3-pole electronic lamp that amplifies the microwave rays, generated from an electromagnetic oscillator. The magnetron’s microwave rays will travel in current in the waveguides (waveguides) to the diffusion fan. The daily diffuser is usually above the oven’s top to spread the microwave rays to all sides. These microwave rays are continuously reflected back and forth in the cooking chamber.
The moisture in foods that are in the cooking chamber is heated. The heat of this water will transfer heat to the rest of the food or food stored in the oven. Heating is divided into two phases: The water in the food is heated by microwave waves, and the hot water transfers heat to other parts of the food.
Microwaves cook food many times faster than traditional stoves because heat is generated both inside and outside the food at the same time. Traditional stoves or frying pans heat the surface of the food first, then with moving inwards. Because the air inside the microwave is room temperature, the food won’t turn dark gray as if it were cooked on another stove.
If you actively find out information related to the structure and principle of operation of the microwave oven, you are interested in your family’s health and safety. After you have mastered the principle of microwave oven operation, you should also learn about the correct ways to use microwave ovens and the capabilities that microwave ovens have to use the microwave most effectively. Please.
How much radiation does a microwave emit?
The radiation from the microwave can ripen body tissue in the same way that the oven cooks food. Microwaves cause water molecules in food to move rapidly and vigorously, generating heat and cooking food.
The human body is more than 70% water, making us hesitate to stand too close to a microwave oven. High levels of microwave exposure can cause severe burns, while the lens in the eyes and testicles in men is the most sensitive to large amounts of radiation. As recommended by the US Food and Drug Administration, there are risks of microwave use such as burns, cataracts, and temporary infertility.
Pregnant women and children are subject to more health care. There is no medical evidence that pregnant women should avoid using microwave ovens for cooking.
However, if your microwave oven is old, it may be more likely to leak radiation or something has been damaged, then you should not continue using it. Your doctor may not recommend using a microwave oven during your entire pregnancy as there is little evidence to support it safe to use it.
However, be aware that microwave radiation, similar to that of cell phones, is non-ionizing, meaning that this radiation cannot change the molecular structure of anything. What’s more, microwaves generate less energy than infrared radiation, the kind of heat our bodies produce.
Even if you take the food out of the microwave, the radiation doesn’t get to your body or cause any harm, as recommended by the US Department of Agriculture.
The FDA allows microwaves to leak 5 mW / cm2 during its operation. The manufacturer is also responsible for checking the microwave glass to prevent radiation leakage. So with new and leak-free microwaves, you can rest assured.
Should You Stand In Front of the Microwave?
There has been controversy about the dangers of microwaves for children, pregnant women, and adults over the past several decades. Since there’s no clear proof, we probably don’t know whether to stand near the microwave to satisfy our curiosity about how the food is cooked or to stand a little further away while the oven is at work to ensure safety.
Since the invention of microwaves in World War II, many homemakers have been skeptical and unwilling to use them because the microwave oven applies a radiation technology that allows Britain to detect aircraft bombing of the Nazis.
However, microwaves allow food to be heated quickly and effectively without harming humans. Percy LeBaron, an engineer who invented the microwave while he passed a machine emitting microwaves, caused the candy bar to melt in his pocket.
Since it entered the market, microwave ovens have become as user-friendly and popular as refrigerators. Thanks to the revolution of design changes in 1940, microwave ovens have reduced exposure and radiation leakage.
However, you should still not stand near an active microwave oven to avoid the radiation’s health effects.
How to prevent radiation leaking from a microwave oven
You should apply ways to prevent radiation leaks from a microwave oven and learn clearly what you need to know when using a microwave.
To make sure your microwave is safe, put a piece of paper in the slot of the door, close the door, and pull it out. If the piece of paper is pulled out of the door slot, your microwave is not sealed and could cause radiation leakage.
At this time, you should replace a new oven because the metal around the microwave is the important part that prevents radiation from leaking. A small amount of radiation can also affect us.
You should keep a safe distance from the microwave, not close your face to the oven door, and should be at least 1 foot away, or about 30 cm because the radiation will decrease very quickly with the distance.
You should also make sure your microwave oven is working properly as if it is old or damaged, or the door cannot be closed, for safety reasons, you should replace it with a new one.
Thus, after our information about how much radiation does a microwave emits, you can see that the radiation density of the microwave oven and the risk to human health have been concluded to be very low and within the safe range for the user. However, you should not stand near the microwave to minimize possible risks.