Speech recognition in noise with active and passive hearing protectors: a comparative study

Area of Science:

• Audiology
• Occupational Health
• Acoustics

Background:

• Standard hearing protectors can hinder communication, leading to non-compliance.
• Augmented hearing protectors are designed to enhance speech intelligibility.
• The actual benefit of augmented protectors requires further investigation.

Purpose of the Study:

• To compare speech perception with active earplugs versus standard passive custom-made earplugs.
• To evaluate the performance of active earplugs with fixed and user-selected amplification levels.
• To assess the impact of different noise conditions on hearing protector efficacy.

Main Methods:

• Sixty normal-hearing subjects were tested using 20 speech-in-noise fragments.
• Realistic industrial noise samples with varying characteristics were used as background.
• Speech recognition scores were collected and statistically analyzed.

Main Results:

• Protector performance was highly dependent on noise conditions.
• Active earplugs with minimal amplification outperformed others in extreme (easiest/hardest) noise scenarios.
• Passive earplugs were superior in other noise conditions, and active protectors limited binaural listening.

Conclusions:

• The efficacy of augmented hearing protectors is context-dependent.
• Acoustic analysis aids in understanding performance but human subject testing remains crucial.
• Further development of active earplugs should consider noise-specific performance and binaural hearing limitations.