What symbol represents uncomfortable loudness levels (UCL) or loudness discomfort levels (LDL) on an audiogram?

On an audiogram, the symbol that represents uncomfortable loudness levels (UCL) or loudness discomfort levels (LDL) is typically depicted as "U." This notation helps audiologists and hearing aid dispensers quickly identify the threshold at which sounds become uncomfortably loud for a patient. Understanding UCL/LDL is crucial in audiometry as it assists in determining safe amplification levels for hearing aids, ensuring that they provide auditory assistance without causing discomfort.

The choice of "U" specifically signifies "uncomfortable," making it straightforward for professionals to track and address the hearing needs of individuals during assessments. Other symbols used on audiograms correspond to different thresholds or measurements, but in this case, "U" is established as the standard representation for evaluating loudness discomfort.