Hearing protection devices and methods used for their evaluation: A military perspective

Introduction: Soldiers are regularly exposed to potentially harmful noise such as the constant noise of transport vehicle engines and the impulse noise of weapons. Impulse noise can be particularly hazardous, especially, for example, the high-intensity noise of artillery or shoulder-fired projectile launchers. After administrative and engineering controls, hearing protection devices (HPDs) are a cornerstone of hearing conservation programs. Yet selecting the appropriate protection for the various mission tasks must be done with care. HPDs can range from simple earplugs to high-tech options. Methods: Methods of characterizing the attenuation of HPDs against high-level impulse noise are complex and evolving. Results: For the soldier, the need to balance the degree of measured sound attenuation against interference with other auditory abilities - such as the need to hear soft sounds, to understand commands, or to localize sound - is a common dilemma. Discussion: This article outlines some of the challenges of assessing and choosing HPDs that keep soldiers safe from noise exposure with a view to helping those new to hearing conservation understand more about this important subject.