Hearing loss defined

Recurrent otitis media is defined as at least three episodes in 6 months or at least four episodes in 12 months. Recurrent infections are of concern because patients younger than 3 years of age are at high risk for hearing loss... 

There are two risk factors a high total cumulative deferoxamine dose and a low serum ferritin concentration. In order to prevent deferoxamine ototoxicity, a therapeutic index has been proposed, defined as the daily dose of deferoxamine (in mg/kg/day) divided by the serum ferritin concentration (ng/ml) (SED-12, 552) (68). A therapeutic index of 0.027 is considered to be associated with a low risk of deterioration of hearing. Regular audiometric follow-up, with special attention to the frequencies of 3 and 6 kHz, can help to detect and prevent permanent hearing loss. 

Ideally statistics for relevant occupational illnesses, noise-related hearing loss and absence from work through sickness should be included in the report. However, to achieve a yes score it is considered that no figures need be presented provided there is a clearly defined group-wide strategy for improving occupational health. 

Of the five traditional senses, vision and hearing mostly define the interactions that permit us to be human. These two senses are the main input channel through which data with high information content can flow. We read, listen to speech or music, and view art. A loss of one or the other of these senses... 

The first four sections of this chapter explain what noise is, how it is defined and the theory and practice behind the measurement of noise levels. The rest outlines the way the ear works and the damage that can occur to cause noise-induced hearing loss. Some of the problems created by vibrations are considered. Reference is made to the guidelines, recommendations and legislation that exist and which are aimed at limiting the harmful effects of noise in the workplace, and the nuisance effect on the community. 

Noise is commonly defined as any unwanted sound. Noise literally surrounds us every day and is with us just about everywhere we go however, the noise we are concerned with here is that produced by industrial processes. Excessive amounts of noise in the work environment (and outside of it) cause many problems for workers, including increased stress levels, interference with communication, disrupted concentration, and, most importantly, varying degrees of hearing loss. Exposure to high noise levels also adversely affects job performance and increases accident rates. 

Hearing loss is presumed to be work-related if the employee is exposed to noise in the workplace at an 8-hour time-weighted average of 85 dBA or greater, or to a total noise dose of 50 percent, as defined in OSHA s Occupational Noise Exposure standard. Noise dose is defined as the amount of actual employee exposure to noise relative to the permissible exposure limit for noise. A dose greater than 100 percent represents exposure above the limit. For hearing loss cases where the employee is not exposed to this level of noise, refer to the rules in 1904.5 to determine if the hearing loss is work-related. 

If a standard threshold shift (STS), defined as an average of 10 dBA or more at 2000, 3000, and 4000 Hz, occurs in either ear, the employer must follow certain procedru-es outlined in the standard, including notifying the affected employee in writing. Hearing loss cases that meet specific criteria must be recorded on the OSHA 300 log according to the recordkeeping requirements of 1904.10. 

Noise is simply defined as unwanted sound. Exposm-e to noise can result in occupational deafness (noise-induced hearing loss), fatigue, speech interference and stress. In some cases, noise can be a contributory factor in industrial accidents. Noise nuisance from, for instance, industrial processes, can result in fatigue, stress and a range of psychosomatic s)unptoms. 

The list of lingering health-related impediments includes CWP, silicosis, hearing loss, and musculoskeletal disorders, which are just now being recognized and defined as a distinct problem. 

The loss of compression in the damaged ear is a possible cause of the phenomenon of loudness recruitment. Loudness is the perceptual correlate of sound intensity. Loudness recruitment is defined as the unusually rapid growth of loudness with an increase in sound intensity [Moore et al., 1985], and often accompanies sensorineural hearing impairment... 

---