Are wireless earphones safe?

How do wireless earbuds work?

No matter what brand of earbuds you’ve chosen, they all work pretty much the same way: via Bluetooth. That much is clear to everyone that’s had to pair a set to their smartphone. Bluetooth is not some vastly different technology. It’s just a widely adopted standard for close-range radio-frequency transmission.

Parts image from iFixit AirPods teardown

You might be surprised to learn that the frequency range in which Bluetooth operates, between 2.4 GHz and 2.4835 GHz, is where you can find the frequency of microwave ovens, which operate at 2.45 GHz. Of course, the big difference is power: the oven operates at anywhere between 600 and 1200W, while Bluetooth earphones are categorized as Class 2 transmitters. This means they can transmit up to 10 meters and operate at 2.5 mW peak transmission power. To give you some perspective, 2.5 mW is 240,000 times less than 600W. In other words, it will take a pair of earbuds months to match the energy a microwave oven outputs in a minute.

When it comes to EMF, it’s not all about power, however. There’s another aspect that should be considered.

Specific absorption rate – what does it mean for you?

Specific absorption rate or SAR is a measurement of how much energy coming from the radio frequency electromagnetic field is absorbed by the human body. It is measured in watts per kilogram (W/kg) and used by regulating agencies to determine if a device is safe to use or not.

The problem is that unlike most other scientific measurements, SAR comes with a few asterisks. EMF waves don’t spread uniformly so the measurement represents the average energy absorbed by a certain volume of tissue. In the US, the FCC has put a limit of 1.6 W/kg for mobile phones, and the value is measured at a point within 1g of tissue that is absorbing the most energy. Europe follows the International Electrotechnical Commission standard, which says anything under 2W/kg over 10g of tissue is safe. Each device has to be tested separately for each standard.

A bigger problem is that the FCC test for SAR is inadequate, to put it lightly. It was designed in 1989 and the dummy head which is used for the measurements is equivalent to that of a 6’2” man that weighs 220 pounds. The human brain is represented by a simple mixture of water and electrolytes. The massive head is subjected to just 6 minutes of peak activity before the measurements are taken. Those are just some of the issues of the test, but they’re enough to show that it’s not representative of the average person’s usage in 2019.

Let’s get back to wireless earbuds

We’re not specialists in the field of electromagnetic radiation and its influence on the human body. That’s why we contacted Dr. Joel Moskowitz, Director of the Center for Family and Community Health at the University of California, Berkley. Besides his work at UCB, he regularly posts studies on the matter on the Electromagnetic Radiation Safety website.

We asked him if the close proximity of the earbuds to the brain significantly increases the effects of their EMF emissions. His response was: "Yes. The AirPods SARs are quite high considering this is a Bluetooth device."

 

While these figures represent theoretical maximums and not necessarily the amount of exposure you're getting during normal use, they show that wireless earbuds are not to be underestimated, especially considering that they're meant to be worn for hours at a time.

Of course, every product you’re using has been deemed safe, or at least the conducted test results were within the required limits, which is the case with the AirPods as well. If you’re interested in details about the testing, you can check the AirPods’ SAR report submitted by Apple to the FCC.

So, are wireless earbuds safe?

While that is the ultimate question, there’s no ultimate answer. Dr. Moskowitz went on to say that the use of any wireless headset is not advisable and that he personally doesn’t use such devices because of their EMF emissions. He’s not alone in thinking that EMF emissions are underestimated. A group of more than 240 scientists from all around the world has signed an international appeal to the United Nations, calling for increased regulation and protection from non-ionizing electromagnetic field exposure.

According to the appeal:



It should be noted that the scientists' concerns are towards EMF-producing devices across the range, from Wi-Fi routers to baby monitors. The accumulative effect from all that surrounds us is what increases the risk for human health more than any single gadget.

Back to the smaller picture of wireless earbuds. There is no conclusive evidence of them being harmful to humans since no studies of the long-term effects of wireless headphones have been made. There is disagreement among experts about the extent of their negative effect. While some are appealing for stricter rules, other think that the concerns are exaggerated and the EMF from earbuds is far too weak to have any noticeable impact on the human body, meaning you can safely ignore their influence. This is currently the common conception.

Of course, manufacturers hold the same stance as well. We reached out to Apple, Samsung and Bose regarding the safety of their true wireless earbuds. Only Samsung got back to us, stating that on top of meeting all the necessary regulations, its “own internal EMF tests confirmed that the devices are fully compliant and safe for daily use”. Regarding the SAR of the Galaxy Buds, Samsung responded with: “Our wireless earphones are designed to minimize the absorption rate and even at maximum power do not generate significant levels of RF exposure”.

While we can’t speak for the other two companies, from our experience, their answers would have likely been very similar to those of Samsung. We didn’t really expect anything else either.

Where does that leave us?

Even if we assume that your handy earbuds do not cause you any harm, one thing is certain – they’re not doing your body any good either. And while smartphones have become pretty much irreplaceable, wireless earphones have only the benefit of being slightly more convenient to use than their wired counterparts.

If you’re a heavy user and have buds in your ears for most of the day, then it might be a good idea to stick to the old-school ways. On the other hand, whatever negative effect wireless buds might come with could be just a drop in the bucket of electromagnetic radiation you’re receiving just by existing in civilization in the 21st century.

Of course, at the end of the day, it’s up to the user to determine what tech to use and how. However, there’s a case to be made about authorities getting up to speed with the tech world and providing more relevant data to consumers, so they can make an informed decision.