The QuickFit device developed by the National Institute of Occupational Safety and Health allows workers to ensure their hearing protection is actually working, preventing hearing loss.
About 30 million workers are exposed to hazardous noise on the job, placing them at risk of permanent hearing loss, tinnitus and other disorders.
While earplugs have protection values, research shows in the real world noise reduction achieved is much lower, even to the extent of zero protection due to poor-fitting earplugs.
While there are personal fit testing devices available, these are expensive and unsuitable for mine conditions.
With this in mind, NIOSH researchers went about creating a simplified variation of the testing device that was low cost and easy to use.
The QuickFit tests that an earplug is blocking noise by 15 decibels. It works by comparing two threshold tests: one without hearing protection and one with an earplug inserted.
The device is placed over the ear and the user adjusts the volume control so the sound is on the edge between audile and too quiet to hear. This is the user’s threshold of hearing.
The user then inserts an earplug and places the QuickFit against the protected ear while pressing the boost button. If this sound can’t be heard the earplug is fitted correctly. If it can be heard the user should refit the plug or try another type and then redo the test.
NIOSH also has a web-based version of the system that can be used.