Do earphones and headphones damage ears?

There is often a false rumor about the correlation between bluetooth and poor health. These beliefs became popular following some doubts that spread in the scientific community in 2015 about the fact that airpods are dangerous for our health: in an appeal published in the journal Medium, 247 scientists from 42 countries were concerned about the excessive exposure to electromagnetic fields caused by bluetooth devices.

In the following years, however, no scientific evidence has come to surface to support this thesis: recent studies have shown that the radiation generated by Bluetooth devices is less dangerous than those emitted by smartphones. In general, the emission of electromagnetic waves is so low that it is irrelevant. In fact, the Bluetooth protocol uses the same frequency bands as the 2.4 GHz wi-fi, but with a lower power.  

Therefore, a healthy use of wireless headphones, not prolonged in time, does not hurt our health, or at least does not have a more negative effect than the one caused by other wireless devices.

To isolate ourselves from external sounds and noises, when traveling or on vehicles, people turn up the volume in their headphones or earphones. The limit for headphone/earphone volume for portable CD players has been set at 100 decibels. However, headphones sold individually can exceed this limit. To make the comparison clearer, here are the decibel levels of common sounds: 110-120 decibels is the sound power of a chainsaw in action or a jet in takeoff, while the sound of the human voice reaches 30-40 decibels.

In addition, we must say that the decibel scale is a logarithmic scale so, for each increment of 10 decibels, the power of the sound is multiplied by 10. Moreover, studies show that the recommended intensity level should not exceed 85 decibels for a maximum of 8 hours during the day: at a level of 100 decibels, the damage could come after only 15 minutes.

Some habits can help to set up a proper routine for our hearing devices. For instance, it is always good to:

• vary the sound listening mode: not only of headphones and earphones, but also portable speakers, as well as directly from the computer in natural remote listening mode;
• moderate the volume and duration of listening: experts recommend using the volume at half the maximum capacity, defined as the safe listening threshold. Smartphones and other audio devices come with special features that can measure exposure levels and notify users when they are at risk of hearing loss right away. Help can also come from applications available on smartphones that display decibel intensity levels and indicate whether exposure to this noise level presents a risk;
• provide ears the necessary recovery time;
• use "psychoacoustic" settings on smartphones: from research come practical solutions for our health, In fact, engineers have developed a mode of sound processing that allows users to experience the same sensations heard through a loud listening even at a lower volume.

Noise cancelling headphones use the advanced technology of active noise reduction to cancel the sound that comes around the person who uses them, whatever it is: city traffic noise, crowded office, local noise. The headphones can reduce the background sounds up to 92%, allowing you to focus only on the music you are listening to, the conversation you are having or the movie you are watching.

Noise cancelling headphones are an interesting solution because they prevent a common attitude in many people who, to counteract the background noise, tend to raise the volume of the devices. Obviously, these headphones, however effective, tend to reduce ambient noise, not to erase it completely: they do not allow to get away from the surrounding environment, you have to imagine like a background buzz.

Bone conduction headphones, unlike normal headphones, use the skull bones to propagate sound by emitting small vibrations on the bones between the jaw and the mandible, close to the ear, leaving it free at the same time to hear the sounds coming from the surrounding environment. These types of headphones can lead to a complete isolation from what is around you, which is why they are widely used by runners. The benefits are many: 

• they do not damage the eardrums and do not obstruct the ear canal, thus avoiding problems with the apparatus; 
• by transmitting the sound directly to the cochlea, they can be a good solution for people with hearing problems or with tinnitus, because they avoid creating a resonance chamber that could accentuate the problem.