Electromagnetic radiation is commonly associated with the electromagnetic wave. When this wave travels through space and hits our body, our body gets radiated. Simply put, electromagnetic radiation is the state where electromagnetic wave hits a certain object.
In fact, the electromagnetic wave is everywhere. We live together with them. Every day, our bodies are exposed to radiation of visible light that comes from the sun.
Some types of electromagnetic waves are safe and don’t cause a significant effect on the human body. However, other types can cause heat due to vibration and even further remove electrons from our body cells which leads to serious health issues.
Have you ever seen someone’s body burnt because of taking a long sunbathing without using any protection of UV lotion? That’s the example of how those electromagnetic waves can cause heat.
The worse is because some of the UV wave (the higher frequency) is considered dangerous, it may have damaged our DNA and leads to cancer.
Types of Electromagnetic Wave
Due to this effect, an electromagnetic wave can be divided into two types: non-ionizing and ionizing radiation. The non-ionizing electromagnetic waves are such as visible light, some UV, mobile phone, microwave, radio, Bluetooth, wifi, etc. While the ionizing wave is X-rays, Gamma-rays, and UV, etc.
1. Non-ionizing Radiation
The term of non-ionizing is derived because the wave cannot get rid of electrons from our bodies. This is considered safe. However, the higher the frequency, the higher the energy, the more ability to vibrate the atom in our cells. In the end, the vibration dissipates heat and burns the cells.
Like microwave oven, this appliance releases microwave and burn the kitchen meat inside the oven.
On the contrary, the visible light which is the non-ionizing wave is highly safe. We are totally exposed to this wave. The photon doesn’t have enough energy to damage our body.
2. Ionizing Radiation
As the name suggests, this radiation can cause an atom to be ionized. Ionized atom is the condition where the amount of electron and protons are not equal. In other words, when it removes an electron from its bond, it’s called ionized.
When our body gets exposed to this radiation, it can cause our body cells in trouble such as cancer and even death.
The reason why they are able to remove body cells because of their high frequency. The higher the frequency, the higher the energy that is carried by the particles/wave (remember the dualism theory). The higher the energy, the higher the chance to break apart an electron from its bond.
How Electromagnetic Waves Generated?
1. Sun, Fire, Light Bulb & LED
Sun is the primary energy source of the earth. It produces photons that carry energy as much as 800 billion megawatts of power [Source] and radiate to the earth in the shape of waves. The photon itself is generated from the nuclear fusion that occurs in the heart of the sun. More about this, read here.
Most of the electromagnetic waves that land on the earth are the visible light, the non-ionizing one. This wave spreads everywhere and reflects on everything. We can see things because those reflections reach our eyes. Our retinas are designed to able to be sensitive to this wave. Other than this wave, our eyes are unable.
Other electromagnetic waves released by the sun are UV and infrared rays. Our eyes are not able to process these waves.
By the way, there is an animal called snake that uses infrared as their vision. Infrared is an electromagnetic wave as well and its frequency is in the range of 1013 – 1014 Hz [Source]. This range is below the visible light.
Other electromagnetic sources are fire, light bulb, and LED. Fire radiates electromagnetic waves in the shape of visible light and infrared. Incandescent light bulb generates visible light and infrared as well as LEDs which releases infrared, visible light, and ultraviolet [Source].
Hey! All of these are everywhere. You are completely radiated.
2. Electromagnetic Field (EMF)
An electromagnetic wave can be generated by an electromagnetic field. And this is human-made that manipulates electricity to turn into an electromagnetic field (EMF).
Things such as mobile phones, walkie talkie, and radio send information (audio) using the electromagnetic wave. Therefore, they are built-in with electronic components that generate the electromagnetic field.
The current that flows along the conductor creates a magnetic field. And the voltage difference between the two spots (dipoles) creates an electric field. The combination of these two fields creates the electromagnetic field.
Since it can be direct (DC) and alternating current (AC), there can be two types of electromagnetic fields. Those from DC current are static EMF and those from AC current are dynamic EMF.
For battery-powered appliances and electronic devices such as walkie talkie and mobile phones, they generally emit a static electromagnetic field. While the power line, 5G cell tower (cellular tower) are the sources of a dynamic electromagnetic field.
A dynamic electromagnetic field generates an electromagnetic wave consisting of electric field and magnetic field. You can see the illustration of the wave on the above picture. This field creates a wave on the air or space. The wave then travels.
What is Radiation?
When it comes to radiation, the term radiation is divided into two groups below [Source]. This division is so much close in terms of how the electromagnetic wave is generated (explained above).
1. Nuclear Radiation
When a subatomic particle is decayed and emitted from the nucleus (proton and neutron) of the atom, the radiation that happens is nuclear radiation. X-rays, Gamma-rays, and UV-rays (ionizing electromagnetic wave) are classified as the electromagnetic that emits nuclear radiation.
Keep in mind that although the term of the electromagnetic wave should consist of all electromagnetic waves including X-rays, Gamma-rays, and UV-rays, in this case, the ionized electromagnetic wave stands alone as the nuclear radiation.
2. Electromagnetic Radiation
This radiation is the product of the electromagnetic field. Engineered by humans, electricity turns into electromagnetic field (EMF). This EMF generates waves consisting of electric and magnetic fields. Radio, for instance, is built-in electronic components that generates the electromagnetic field (EMF). The EMF then released to space and carries information.
In other words, EMF radiation is the radiation that comes from non-ionized electromagnetic wave generators. All devices that generate electromagnetic field (EMF) are considered as the source of EMF radiation.
Types of EMF Radiation
Further, the non-ionizing electromagnetic field (EMF) is classified into three groups: 1. Radio Frequency (RF), 2. Intermediate Frequencies (IF), and 3. Extremely Low Frequencies (ELF)
Based on the Frequency
1. Radio Frequency (RF).
Things such as cellular phones, microwave, cell towers, cordless phones, smart meter, wifi, radar, and radio are the sources of electromagnetic fields that emits electromagnetic wave radiation between 100 kHz to 300 GHz frequency.
2. Intermediate Frequencies (IF)
Devices such as the monitor, computer, laptop, and metal detector generate an electromagnetic field that radiates wave in the range of 300 Hz – 100 kHz.
3. Extremely Low Frequencies (ELF)
The power lines near your lovely house can distribute the ELF electromagnetic wave which is typically 0 – 300 Hz in frequency. In general, the powerline has a frequency of 50 or 60 Hz.
EMF Radiation Commonly Measured
However, in reality, EMF radiation always refers to these three things: Electric Field, Magnetic Field, and Radio Frequency Radiation. It’s not weird that you’ll find EMF meters always measure these three things.
Some of them measure these three in a single device. While some measure only the RF. The EMF meter for ghost hunting, for another instance, is designed to be simple and only detects the magnetic field.
1. Electric Field Radiation
When it comes to electric field radiation measurement, it means the electric field strength measurement. It’s a potential difference in voltage between two points which are separated at a certain distance.
The unit to measure the electric field radiation is Volt per meter (V/m). Some countries have different regulations of limit exposure to electric field radiation. Furthermore, the limit for worker and public are also different.
2. Magnetic Field Radiation
Measuring the magnetic field radiation means measuring the magnetic induction or the magnetic flux density. Don’t get confused, magnetic field and magnetic flux density are not the same. Tesla and Gauss are used as the unit.
Other similar units such as µT (micro Tesla) and mG (milliGauss) are common as well. Tesla is used in Europe, while Gauss is usually used in the United States. The value of 1 Tesla is equal to 10000 Gauss. The Standard International (SI) unit is Wb/m2.
3. Radio Frequency (RF) Radiation
Simply put, power density is measured to measure RF radiation. Power density means power flow per unit area which can be expressed in W/m2 (read: watt per meter square). Another similar unit is mW/m2 (read: milliwatt per meter square).
The power density actually refers to the total electromagnetic field which consists of the electric field (Volt/meter) and magnetic field (Ampere/meter). Keep in mind that the magnetic field and magnetic flux density are actually slightly different.
How to Measure EMF Radiation?
Although it’s considered safe, in some countries, there is a limit of EMF exposure that is issued by the government.
By using the measuring device called EMF meter, you could measure the EMF radiation easily. However, you need to understand some basic measurements such as the unit reading used in EMF measurement. Even further, you could learn how the device works.
Be careful when measuring EMF. It’s important to get the measurement as accurate as possible. In this case, there is our post that covers the best EMF meter. This post will give you a selection of EMF meters and consider what we recommend.
Limit Exposure of EMF Radiation
Each country has different regulations of limit exposure to EMF radiation. Moreover, the limit for the workers and the public is different. Further, each year, the limit also changes.
In this case, since it’s changing, we are going to ask you to visit this page for your further exploration. It contains the table of limit exposure for each country, each division (workers and public), year, and others.
Overall, although the term “electromagnetic wave” means the wave that consists of electric field and magnetic field, when it comes to EMF radiation, it commonly refers to these 3 radiations: electric field radiation, magnetic field radiation, and radiofrequency radiation.
To measure electric field radiation, we measure the electric field strength. To measure the magnetic field radiation, we measure the magnetic flux density. And lastly, to measure the RF radiation, we measure the power density.