## Which headphones are more dangerous? To study the effect of headphones on human hearing, the US Center for Disease Control and Prevention (CDC) tested over 3,500 volunteers. Hearing impairment was found in a quarter of the study participants, more common among men than women. One-fifth of those with hearing problems were young people aged 20–29, almost all of which were fans of loud music and used headphones on a regular basis. Other studies have shown that the type of headphones can impact hearing. In descending order, the headphone hazard rating looks like this: - Earplugs (those that are inserted directly into the ear canal, cutting off external noise using silicone seals) - In-ear headphones (those that are inserted into the auricle, but do not penetrate into the ear canal) - On-ear headphones (those that are applied on the ears and are connected by a semicircular bow that holds the headphones on the head) ## What is high volume? High volume is a subjective characteristic, but experts believe that the volume of music in headphones should not exceed 65–80 dB for a maximum of 40 minutes with a subsequent break for several hours. How do you measure these decibels without instruments? For comparison, whispering is 20 dB, a calm conversation is 30–35 dB, a cry and loud laughter is 75 dB, music in nightclubs is 100 dB, and a jet engine is 140 dB. The choice of music volume in headphones depends on the hearing acuity of the specific person, his or her habits, and the noise level of the environment. The louder the noise, the more you want to turn up the volume in the headphones. To suppress the sounds of a modern metropolis, you usually have to turn on music at 90–110 dB—which is close to the level of a jet engine! ## A matter of technology You shouldn't skimp on headphones. There are many counterfeit products of famous brands on the market. In addition to poor assembly, they often produce a sharp, unbalanced sound in frequency, which at high volume is much more damaging than high-quality headphones. It is better to use open-back headphones at home. And avoid acoustic systems that get too loud, as they can damage the ears. When choosing headphones, pay attention to ear pads (silicone seals, ear pads). They should be comfortable and properly cut off external noise. This will allow you to listen to music at a lower volume, which means less harmful effects on the ears. A comfortable volume level is where the frequencies of the middle range are best heard by the listener. If you cannot achieve complete isolation from external noise, you should not try to drown it out by turning up the volume. It is better to listen to music some other time than to force your hearing to the limit. ## Checking your hearing On any radio, tune in to the "spoken" (not music) mode. Set the volume to the lowest level, just enough to understand what the conversation is about. Then listen to music through headphones at your usual volume for half an hour. Return to the radio. Most likely (if the music in the headphones was loud enough), the conversation that you could make out half an hour ago is now difficult to understand. Experts call this a temporary decrease in the sound threshold. In this way, the ears protect themselves from overload. The previous hearing acuity is fully restored in a day. However, remember that this effect tends to accumulate and can lead to permanent hearing impairment.