Abstract: A hearing protection device (500) arranged to provide an acoustic barrier is disclosed. The hearing protection device (500) includes a microphone (502) arranged to measure sound behind the acoustic barrier. The device (500) determines whether a sound level characteristic of the sound measured by the microphone (502) is above a predetermined threshold. When the sound level characteristic measured by the microphone (502) is above the predetermined threshold, the device (500) compares the sound level characteristic of the sound behind and outside the acoustic barrier to determine an attenuation of the device (500). If the determined attenuation is below a cut-off level of attenuation, the device (500) provides an alert.

Abstract: A system including an acoustic barrier suitable for wearing in or on an ear of an individual mammalian subject, and a processor. The acoustic barrier defines at least one sound path therethrough and includes a microphone for measuring sound pressure inside the acoustic barrier. The processor is arranged to receive measurements from the microphone and determine a risk that a sound dose limit will be reached before a predetermined time associated with the dose limit. The system is arranged to provide an indication of the determined risk.

Abstract: A system including an acoustic barrier suitable for wearing in or on an ear of an individual mammalian subject, and a processor. The acoustic barrier defines at least one sound path therethrough and includes a microphone for measuring sound pressure inside the acoustic barrier. The processor is arranged to receive measurements from the microphone and determine a risk that a sound dose limit will be reached before a predetermined time associated with the dose limit. The system is arranged to provide an indication of the determined risk.