Measuring How Well Earplugs Work

A Story of Impact :

Each year an estimated 22 million workers are exposed to noise loud enough to harm their hearing.¹ The problem crosses many industries, including manufacturing, construction, agriculture, mining, and transportation. When noise levels cannot be reduced through engineering controls, the Occupational Safety and Health Administration (OSHA) requires that workers use hearing protection devices (HPDs) to protect themselves from the damaging effects of noise. Despite decades of OSHA-mandated HPD use, noise-induced hearing loss (NIHL) remains highly prevalent.

All HPDs sold in the U.S. are evaluated in a test laboratory and labeled with a Noise Reduction Rating (NRR). However, studies have repeatedly demonstrated that the NRR does not accurately predict noise reduction performance for an individual in the workplace. Research shows that most workers achieve less than half of the sound attenuation predicted by the NRR.² The difference between the NRR and actual worker attenuation varies widely across different types of protectors and different ear canal sizes and shapes. Personal hearing protector fit-testing is the only way to know how much noise reduction an individual receives and to ensure that each worker is sufficiently protected from excessive noise.

The National Institute for Occupational Safety and Health (NIOSH) developed the HPD Well-Fit™ system to create a fast and reliable fit-test system not anchored in proprietary technology. HPD Well-Fit™ measures the amount of sound reduction an individual worker receives from their HPD and identifies workers who are not sufficiently protected. HPD Well-Fit™ requires only a computer running the Windows operating system (version 7 or later) with a high-definition sound card, a mouse with a scroll wheel, and sound-isolating headphones. It can be used to test any type/brand of earplug and provides results within 7 to 10 minutes. HPD Well-Fit™ expedites the collection of repeat measurements, so retraining and retesting can be conducted in just 2 to 5 minutes. The HPD Well-Fit™ system is fully customizable, allowing the user to select which frequency bands (125 to 8000 Hertz) are tested and choose the best protection for different noise conditions.