NAL
Pronunciation: N-A-L
Also written as: NAL — National Acoustic Laboratories
National Acoustic Laboratories hearing aid prescription formula that calculates optimal amplification based on hearing thresholds.
Full Definition
NAL (National Acoustic Laboratories) refers to a family of evidence-based hearing aid fitting procedures developed in Australia that prescribe optimal gain and output characteristics based on individual hearing loss patterns. The most current version, NAL-NL2, aims to maximize speech intelligibility while maintaining acceptable loudness for a wide range of inputs. NAL prescriptions consider factors including hearing thresholds, age, experience with amplification, and bilateral versus unilateral fittings. These formulas provide target gain values that hearing aid software uses to automatically program devices, though clinical fine-tuning may be necessary based on patient preferences and real-world performance.
Usage
Usage note: Capitalize all letters; specify version (NAL-NL2, NAL-NL1) when precision is required.
In Context
- "The hearing aids were programmed using NAL-NL2 targets with minor adjustments for patient comfort." — Hearing aid fitting documentation
- "NAL prescriptions typically provide less high-frequency gain than DSL formulas for pediatric patients." — Fitting protocol comparison guide