What should the interaural attenuation value be for bone conduction (BC) masking?

In the context of audiology, interaural attenuation refers to the reduction of sound intensity that occurs when sound travels from one ear to the other. For bone conduction masking, the established interaural attenuation value is typically set at 40 dB. This is because, when testing bone conduction, the vibrations are transmitted through the skull and may be detected by the non-test ear, leading to the necessity of masking the non-test ear to ensure accurate threshold determination.

Using a value of 40 dB allows audiologists to account for the crossover of sound energy and ensures that threshold results are representative of the ear being tested. Bone conduction testing can yield results that are influenced by the hearing status of both ears. Therefore, it is essential to use this interaural attenuation value to provide adequate masking to the non-test ear and to ensure the test results reflect the true auditory capacity of the test ear.