Final answer:
Additional masking is not required in SRT testing when hearing levels in both ears are similar or when noise does not cross over to the non-test ear. It is required to ensure accuracy when significant hearing differences are present. Masking techniques vary based on individual hearing profiles.
Step-by-step explanation:
For Speech Reception Threshold (SRT) testing, no additional masking is required if the level of hearing in both ears is fairly similar, or if the intensity of the test sound in the non-test ear is not loud enough to cross over to the other ear. Additional masking is required when there is a significant air-bone gap or when there is a notable difference in hearing sensitivity between the ears. Masking prevents the non-test ear from detecting the test sound, ensuring the accuracy of the results for the test ear.
When complete silence or a masking noise is introduced to the non-test ear, it ensures that responses are only from the ear being examined. This controlled testing is critical for determining the correct hearing levels and diagnosing any hearing loss accurately. Audiologists use various masking noises depending on the patient's specific needs and hearing loss configuration.