Noise-canceling headphones harm to the ear and ordinary headphones, depending on the size of the volume of use and use of the length of time, the noise reduction function itself does not produce harm to the human ear. 1. Time: If the human ear is exposed to headphones for more than 6 hours continuously, there is a risk of hearing damage, so we should pay attention to the length of use when using headphones, and take a break for 10 minutes after half an hour of use, and try to avoid using headphones for a long period of time. 2. Volume level: The World Health Organization recommends determining the hearing safety level of personal audio devices, setting their volume in a quiet environment at a comfortable level of no more than 60% of the maximum volume, to ensure listening within the hearing safety range. It is recommended that when using headphones, the volume should be minimized when you can hear clearly to mitigate damage to the human ear. Therefore, although noise-canceling headphones do not produce greater harm than ordinary headphones, the use of the process still need to pay attention to the length of use and headphone volume, or reduce the frequency of use of in-ear headphones.