It is the dawn of a new era.
The 5G era.
A network technology that is promised to disrupt industries, enable countless innovations and take us one step closer to The Jetsons.
We know most major carriers around the world are already working hard on building their 5G networks. In the US, specifically, AT&T has just launched the first commercial 5G-capable device, the Netgear Nighthawk 5G mobile hotspot. As for phones, the first 5G models are expected to land in the first half of 2019, so it's safe to say we're almost there.
As the first 5G towers are beginning to go online, though, and as we're starting to learn more about what makes the technology tick, like the fact that 5G will be capable of operating at much higher frequencies than current 4G LTE networks, some customers are beginning to express concerns if this new technology will be safe, or at least be as safe as what we have right now.
So far, carriers have been using spectrum bands anywhere from 600MHz to 2.6 GHz to deliver the goods to us. This is the low end of the microwave range. With 5G, however, some way higher frequency bands will be opened for service, including the so-called millimeter waves, which you might have heard of. To be clear, some lower-frequency spectrum like T-Mobile's 600 MHz or Sprint's 2.5 GHz will also be utilized for 5G transmissions, but carriers will increasingly be taking advantage of higher bands, such as 3.5 GHz, 6 GHz, and even 30 GHz, and up! 30 GHz sounds too much? That's where those millimeter waves actually begin!
While we still don't know exactly what bands AT&T's Netgear Nighthawk 5G hotspot works on, AT&T has said the device will be using millimeter waves. So we know the Nighthawk 5G, powered by Qualcomm's Snapdragon X50 5G Modem, will be cruising at or above 30 GHz. Why? Millimeter waves are found in the range of 30 - 300 GHz. That's because a wave with a frequency of 30 GHz has an approximate length of 10mm, and a wave of 300 GHz has a length of 1mm. It's safe to say that even if some higher bands are eventually unlocked for 5G use, the technology probably won't exceed the millimeter range during its entire lifetime.
Now, the million dollar question is...
You might hear some say that these millimeter waves are of such high frequency that they'll eventually fry your brain. Thankfully, that doesn't seem to be the case at all! As high as 30 GHz may seem to us today, the reality is these waves won't be nearly powerful enough to do any harm.
There are electromagnetic waves of unbelievably higher frequencies out there, and beyond a certain threshold, those do become dangerous to living beings partying down here on Earth. The good news is this danger-danger threshold is way higher than 30, or even 300 GHz!
To find where this threshold is, we must ask:
Image by the University of Washington
So we know these new 5G bands of about 30 GHz or above won't be powerful enough to do any harm to us. Phew, that's good to know, isn't it?
So what could be dangerous?
As we established, the so-called millimeter wave range extends up to 300 GHz waves. That's also the far reach of the entire microwave range. What follows beyond microwaves is the infrared range, also sometimes called infrared light. Generally invisible to the human eye, infrared waves span the range of 300 GHz to 385 THz (Teraherz)! Thus, infrared waves have lengths varying from 1 mm (the shortest microwave length) to 780 nanometers (1000 nanometers equal 0.001 of the millimeter, just for orientation).
Radiation types by wavelength and frequency
Infrared radiation obviously has many uses here on Earth, and it's also not of the dangerous type. In fact, more than half of the energy from the Sun (heat) is said to reach Earth in the form of infrared radiation. Thank you, infrared!
So, as these cute and tiny waves get more and more intense, they eventually move into the spectrum of what we perceive as "visible light", which includes wavelengths of 700 nm to 400 nm, or frequencies of 430 THz to 790 THz. Thankfully, the visible light spectrum is not harmful to organisms here on Earth as well.
What follows after visible light, however, gets us into harmful territory.
Ionizing radiation means the radiated particles have so much energy they can actually disrupt electrons from molecules or atoms, causing them to acquire a positive or negative charge. Now, we're no physicists here so we can't explain the technicalities, but apparently that's bad! You don't want ionization on your body! So, somewhere within the ultraviolet spectrum is where things start getting dicey.
Above ultraviolet, there's the x-ray range (10 nm to 0.1 nm / 30 Petaherz to 30 Exaherz). Everyhing above the ultraviolet spectrum is ionizing, and so this applies to x-rays too. As we all know, though, small doses of this are not considered harmful, and can actually help our welfare through medical applications.
Finally, there are gamma rays (wavelengths less than 0.1 nm and frequencies of more than 30 EHz). Being quite adept at penetrating matter, these little, ionizing rascals should be avoided like the plague, when not used in controlled and constructive manner (they do have applications in medicine and industry).
Well, now we know! Radiation is categorized into non-ionizing and ionizing. Non-ionizing types of radiation, like radio, microwave, infrared and visible light are considered safe, while ionizing types, like ultraviolet, x-rays and gamma rays are potentially dangerous.
While 5G is expected to employ a higher range of frequencies than previous cellular technologies, it'll still be found safely within the confines of the microwave spectrum, including those millimeter waves. "Millimeter waves" may sound scary to some, but currently there is no reason to believe that 5G networks in themselves are going to be dangerous.
Having all this in mind, we should feel safe in this new 5G world that is about to occur, fully enjoying the quality of life improvements it's going to bring about.