What type of masks are needed when testing bone conduction if a 15 dB difference exists?

In audiometric testing, a mask is used to prevent the non-test ear from hearing sounds presented to the test ear, ensuring accurate results. When evaluating bone conduction, a 15 dB difference suggests that the non-test ear does not contribute to the perceived sound for the test ear. In cases where the difference is 15 dB or less, masking is not necessary because the possibility of cross-hearing is low.

This means that the sound presented to the test ear through bone conduction is not likely to be heard by the non-test ear at a significant level where masking would be required. Therefore, in this scenario, no masks are needed to secure the validity of the bone conduction testing.

Understanding this principle is crucial for conducting accurate audiometric evaluations, as it avoids unnecessary complications and ensures that the test results reflect the true hearing capabilities of the individual.