According to the CDC, four million workers go to work each day in damaging noise, while ten million in the U.S. suffer from noise-related hearing loss. Hearing loss accounted for at least 14% of occupational illness in 2007, and ap- proximately $242M is spent annually on worker's compensation for hearing loss disability. To address this problem, employers are required by law to implement hearing conservation programs for employees at risk. Potential risk is determined by measuring cumulative noise exposure using personal noise dosimeters (PNDs). These instruments are typically worn on-the-shoulder as a surrogate position for center-of-head measurements. The in-ear PND (iPNDTM) is a relatively new dosimeter that has signi?cant advantages over traditional systems because iPNDsTM measure noise in the ear canal using a microphone located interior to any hearing protection. Traditionally, the protected exposure level is estimated by subtracting the noise reduction rating (NRR) of the hearing protection device (HPD) from the on-the-shoulder exposure level which can be an inaccurate estimate. This problem is well documented and contributes to noise induced hearing loss (NIHL) because the employee may be subjected to higher exposure levels than estimated. The iPNDTM avoids this shortcoming by directly measuring protected exposure when the user is wearing an HPD. Although these dosimeters provide superior performance and function, only two, are commercially available today. Their lack of popularity is primarily due to wires that connect the earplugs to a dosimetry processor, creating a nuisance and potential snag hazard. A wireless iPNDTM (wiPNDTM) that would solve the aforementioned problems is proposed. A relatively new wireless technology can be used to transmit noise level data from a wiPNDTM earplug to a remote processor. Novel new features are provided with this system that will help prevent NIHL and improve acceptance of PNDs.
The aim of the proposed wireless in-ear noise exposure monitor is the prevention of occupational noise induced hearing loss. This is achieved through in-ear noise dose measurements using an RFID wireless earplug to mea- sure actual protected exposure as opposed to estimating exposure using potentially non-representative laboratory measurements and arbitrary derating schemes. The comfortable, inexpensive and simple to use system with novel features will ensure widespread user acceptance and signi?cant impact on hearing loss prevention in the workplace.