Uncomfortable Loudness Level
Also written as: UCL — Uncomfortable Loudness Level
The intensity level at which sound becomes intolerably loud for a listener, used to set the upper limit of hearing aid amplification.
Full Definition
The uncomfortable loudness level (UCL), sometimes called the loudness discomfort level (LDL), is the decibel level at which a listener reports that sound is uncomfortably loud. It is measured clinically to define the upper boundary of the dynamic range and to prevent over-amplification by hearing aids. In fitting documentation and aural rehabilitation reports, UCL values are critical for programming output limiting and compression. Editors should note that UCL and LDL are used interchangeably in the literature but some style guides prefer one form; consistency within a document is essential. The measurement should always be accompanied by its reference standard (dB HL or dB SPL).
Usage
Usage note: UCL and LDL are synonymous; editors should standardize to whichever form is house style and flag inconsistency. Always state the dB reference.
In Context
- "The UCL was recorded at 95 dB HL, providing a dynamic range of 55 dB for this patient." — Audiological assessment report
- "Care was taken to distinguish the uncomfortable loudness level from the most comfortable loudness level in the fitting rationale section." — Hearing aid fitting documentation