ITU-T P.360

It is known that an excessive acoustic pressure level may produce auditory damage to the users. To prevent the occurrence of excessive acoustic pressure generated by the earphones of handset or headset, the telephony terminal equipment needs to implement devices to limit the acoustic pressure level. This Recommendation proposes limits to the acoustic pressure generated by the handset and headset earphones and some guidance on how to measure it. It also provides guidance on how to assess acoustic sound exposure of telephone users. It also includes some guidance to avoid speech degradation due to the use of devices implemented in the terminal to prevent the occurrence of excessive acoustic pressure.