There has been a lot of concern the last decade about cell phone radiation and the notorious SAR value. For many people, SAR does not matter at all when it comes to choosing their next device; others swear by it and seek the least possible number. In this guide, we will define the SAR value, and investigate whether or not it is critical for our health.
Table of Contents
- Cell phones and radiation
- What is the SAR value?
- Is a high SAR value dangerous?
- How reliable is the SAR value?
- Do Chinese phones have a higher SAR value?
- How can I find the SAR value of my device?
- How important is the SAR value for you?
Before we start, we want to make clear that we are not scientists nor doctors. The information mentioned below is based on research over the Internet and expresses our personal opinion on the subject.
Cell phones and radiation
It is no secret that mobile phones use electromagnetic radiation, everybody knows that. The radiation they emit to communicate with a cell tower us in the spectrum of radio waves.
This means that the frequency emitted is between 450-2100MHz, depending on our device and our carrier's network.
WiFi, radars, and microwave ovens emit radiation in the same range. But let's have a closer look on cell phones and the way they communicate with a cell site.
Cell phones use radio waves to communicate with a cell tower, at the frequency we mentioned above. These waves can "carry" our voice or other data through the air at the speed of light.
These waves are transmitted in all directions. Furthermore, they can be absorbed or reflected by other objects of the surrounding environment.
As a result, when we talk on the phone and keep our cell close to our ears, a part of the emitted radiation is absorbed by the body.
Each cell phone has at least one radio antenna. An antenna can receive or transmit the signal to the cell site. Therefore, it is used as a transmitter to convert the phone's signal into radio waves. At the same time, it works as a receiver, to do the opposite.
Older cell phones used external antennas to transmit the signal.
However, nowadays smartphones have built-in antennas for convenience. Most of the time, they have several kinds of antennas, such as for WiFi signal, Bluetooth, GPS, and so on.
One of the most common phrases we use regarding our cell phones is that we are "don't have a good signal." But what do we mean exactly by that phrase?
As we already mentioned, cell phones are both transmitters and receivers. The magnitude of the received signal is the so-called "signal strength" of a mobile phone.
We can check our device's signal strength at the top right corner of the cell phone. It is usually represented by vertical lines, and the more we see, the better.
Many variables can affect our Connectivity. First of all, it depends on the potential of a cell phone's antenna. Moreover, the distance between the antenna and the cell site, as well as the "obstacles" between them can play a significant part. Last but not least, the type of the technology used (e.g. GSM, 3G, etc.) can impact our signal strength.
In general, we can attribute poor signal strength in the majority of situations to two factors:
- The cell phone is too far away from a cell site.
- The signal is interrupted by surrounding objects (e.g., buildings, elevators).
In these cases, the cell phone emits more radiation, to communicate with a tower.
It is worth noting that signal strength can have an adverse impact on our battery life.
If the signal is weak, and the phone needs to emit more radiation, the battery drains much faster.
Apart from that though, can radio waves impact our health in any possible way?
What is the SAR value?
The Specific Absorption Rate (SAR) is a number that measures the rate at which energy is absorbed by the human body when exposed to radio waves.
In mobile telephony, we use the specific absorption rate to measure the energy absorbed my a particular mass of human tissue, within a certain amount of time. We measure SAR in units of power per mass (W/kg).
In other words, SAR is nothing but a simple way to measure a cell phone's radiation broadcasting capabilities. This helps us to make sure that a device doesn't exceed the maximum limits set for our safety.
How do we calculate the SAR value
To make an SAR measurement, we must set a quantity of mass. Measurements are usually performed either on the whole body or tissue samples.
When measuring the SAR value, cell phones are placed against a representation of a human in a talking position.
Here you can see a video of the process.
To determine the SAR value, a smartphone is tested under the worst case scenario, so as to emit the highest radiation levels possible.
At the same time, measurements are taken at various distances between the phone and the head, to simulate the way each user holds their phones.
The largest of these measurements defines the SAR value of the tested device.
As we mentioned above, mobile manufacturers conduct SAR measurements under the worst case scenarios. Thus, the SAR value that we can usually find printed on the manual is the highest possible value of that particular device.
In the United States, phones should have an SAR value below or at 1.6 W/Kg, taken over the volume containing a mass of 1 gram of tissue. In Europe, the limit is at 2 W/kg, but in a sample of 10 grams of tissue.
That doesn't mean that in Europe they have a higher allowed limit than in the US. We can not compare the two values because they refer to different amounts of tissue.
For example, if we have a device with 1.2 SAR value by European standards and a different phone with 0.9 in US standards, we can not conclude that the first one emits more radiation than the latter. We should always make comparisons between SAR values measured on the same amount of tissue.
We should always make comparisons between SAR values measured on the same amount of tissue.
Is a high SAR value dangerous?
That is a question we hear a lot. Is cell phone radiation dangerous? If so, does the SAR value help us to choose a safer device?
There are so many scientists working on this, and there has been a lot of research, but nobody can definitively claim that radiation causes health problems. Neither the opposite though. And that's where things get complicated.
According to a recent study, experiments with radio waves conducted in mice resulted in cancerous tumors.
However, there is some fine print that we should take under consideration.
First of all, mice are not humans. You obviously knew that already. Their tissue may react differently to radio waves than human tissue.
Also, the amount of radiation used was seven times higher than the amount of radiation a person is exposed to, with an average daily usage of a cell phone.
In other words, you would have to talk on your phone 10 hours daily for months, to be exposed to such an amount of radiation.
We know for sure that radio waves are considered safe for humans. Although radars operate on the same spectrum, we are not going to stand in front of a radar antenna, are we?
Therefore, the wavelength itself is not the only thing that we should take under consideration. Signal strength and exposure time play a significant role if we want to determine what is safe and what's not.
Scientists and research always lead to the same conclusion: It is possible that constant exposure to radiation from cell phones may cause health issues, but we are not in a position to know it or to prove otherwise, as of yet.
In conclusion, nobody can make a clear statement on whether long-term cell phone usage is safe or not.
For our part, we can only follow the simple rules mentioned below to minimize exposure. Better safe than sorry, but always without exaggerating and panicking.
Beware of the scams
As it happens with any similar situation, many try to make a profit out of other people's fear and despair.
Cell phones are no exception, and we have seen in the market several devices, "special" hats, and magic helmets, that promise to keep you safe from radiation.
We suggest that you deal with caution with products like that. Do your research, be skeptical, and smile.
How reliable is the SAR value?
The SAR value is used as a reference on whether a device is considered safe for sale or not. But it is not a reliable criterion for choosing between two devices.
Let's take for example smartphone A with an SAR value of 1.2 and smartphone B with 0.8.
Smartphone A may have scored higher on one of the measurements (e.g. with no signal and far away from a cell site), with the rest of the measurements being significantly low - around 0.6. Its SAR value is determined by the highest measurement; it is not the average of all measurements.
In the same way, smartphone B may have responded better in the worst case scenario with a 0.8, but all the other measurements were around that number too.
In this case, the user will receive higher amounts of radiation from device B under normal conditions, than with device A.
This example shows how the SAR value can be misleading, and shouldn't be a priority when picking your next smartphone.
What SAR doesn't show
The radiation a cell phone emits increases sharply in places with a weak signal, as we explained above.
So, what good is to have a smartphone with 0.8 SAR, if it consistently operates at the higher levels, due to lack of signal?
A different device with higher SAR may have a better antenna and therefore better signal in everyday use. With a better signal, it may emit less radiation than the first.
The same applies to the distance between the phone and the body. Each user holds his mobile differently, others use headsets, etc. Even the smallest change in holding angle and grip may change both the radiation emited and the percentage of radiation absorbed.
SAR values don't provide any such information. We can't possibly tell how much radiation our body absorbs, just by checking the SAR value.
Do Chinese phones have a higher SAR value?
Another issue people worry about is the SAR value of Chinese phones. It is rumored that Chinese phones have a higher SAR value than other devices, and thus they can burn our brain or something...
Firstly, if a phone is on the market, it means it has passed all the necessary tests, and its SAR value is below the permissible limits.
Moreover, we already mentioned that a higher SAR value isn't always the worst choice, but let's have a closer look at the above claim.
Although we didn't find many websites that include all phone manufacturers and sort devices by SAR levels, we managed to do a comparison of SAR ranges, thanks to PriceSpy and its filters.
So we checked which phones have the highest SAR values in European standards (1.5 W/KG and above).
Huawei is first on the list, with Motorola coming second on older phones.
When we lowered the SAR between 1 to 1.5 W/Kg, the results changed a lot.
In this category, the majority of phones are Apple's and Samsung's, while we can see several models of Huawei, LG, Motorola, and other companies - Chinese or not. We found a total of 102 devices, as opposed to the 15 of our first search.
Let's move down a little further, at 0.5 to 1 W/kg.
At this levels, PriceSpy found 220 devices, which include representatives from all known companies. The same applies to the smallest SAR levels of 0 to 0.5 W/Kg, with 130 devices in total.
As we saw, the only Chinese company on the higher levels is Huawei, along with one Lenovo device. In the same list, we can find the iPhone 6.
It would be wrong to conclude that all Chinese phones have a high SAR value. We certainly found Chinese devices with an SAR below 0.5, and on the contrary, there are more expensive devices on the upper end of the list.
So the answer is "No." Chinese phones won't kill us faster than any other smartphone - if it turns out that radio waves are harmful to us.
Be cautious though; we are talking about known Chinese brands, such as Xiaomi, Meizu, Huawei, and other. The same might not apply for rip-offs like the goophone below, which might not as well regulated, if at all.
How can I find the SAR value of my device?
There are several ways to find your device's SAR value.
The simplest one is to check your phone's manual. Manufacturers usually include SAR values for head and body.
If they don't mention the SAR value in the manual, you can search you specific phone model online, in websites like this one.
All you need to do is type your model on the upper right corner...
...and see the results for the US or Europe.
This website has a huge number of phones, so it is unlikely that you won't find yours.
Note that the page is called "SAR Shield" and it promotes some shield against radiation. We do not know what product they sell and - frankly - we don't care. We used the website only to research the SAR values.
If by any chance you didn't find your phone on that list, you can always Google your product.
In some rare cases you can get a device's SAR with the following USSD code:
You understand so far that the SAR value is not even slightly as important as the time we spent on our phones, the way we hold them, or the signal strength.
There are various safety measures we can follow, to reduce possible future problems on our health.
Use a headset
The number one rule is always to use headphones when talking on the phone.
It is the easiest way to avoid any negative consequences, especially if you are going to spend a lot of time talking on the phone.
Use the speakerphone mode
If you are home alone, and you have a quiet enough environment, you can use the phone's speakerphone mode.
Keep the cell phone away from the body
In case you don't have headphones or you are in a public place and can't use speakerphone mode, you can hold your phone at a distance from your head.
Avoid using your smartphone in places with weak signal strength
We already said that poor signal strength equals to more radiation. And to be honest, just the anger issues we can face when we have a weak signal strength is bad enough for our health - and possibly our phone's integrity.
Therefore, it is advisable to avoid using your phone in places with poor reception.
Avoid using your phone on the move
When we travel by car or any other means, our cell phone continuously tries to adjust to signal changes, and that can be as bad as having a weak signal.
Reduce your overall cell phone usage
Smartphones are probably for many of us the device we use the most during the day.
Above we saw that there is no evidence to suggest that cell phones can harm us. The chances are that other daily bad habits cause more damage, like smoking or drinking alcohol.
This doesn't mean we have to stick our phone on our heads the whole day or carry them in our pockets all the time. Moderation is the key to everything, and smartphones are no exception.
How important is the SAR value for you?
Do you check the SAR value before you buy a cell phone? How important do you believe that SAR is? What is your opinion on cell phones and health? Whether you agree or disagree, you can share your experience with us in the comments section.
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