Harmful noises are everywhere. “The National Institute of Occupational Safety and Health (NIOSH) reports that approximately 30 million Americans are exposed to daily noise levels that will likely lead to hearing loss” (Daniel, 2007, p. 226). Excessive noise exposure can lead to permanent hearing loss, tinnitus, poor communication abilities, and reduced self-esteem; however, it can be prevented in many situations. This paper will discuss how much noise exposure can occur before it becomes hazardous, the long-term effects of noise exposure at an early age, and the primary reasons why preventable socioacousis occurs.
The amount of damage resulting from noise exposure depends on the intensity level of the noise in relation to the length of time exposed to the noise. According to NIOSH, sound levels that exceed a time weighted average of 85 decibels dB(A) over an 8-hour period of time are considered dangerous. It is recommended that exposure time be decreased by half for every 3 dB increase in intensity that exceeds 85 dB because noise exposure increases with time and intensity (NIOSH, 1998). Impulse sounds such as gun fires or firecrackers can exceed 150 dB(A) and cause immediate, irreversible, sensorineural hearing loss (Axelsson & Jerson, 1985). Most people are unaware of the decibel system and how much 85 dB equates to, but according to the article, “How loud is too loud? Minimize noise exposure to protect your hearing”, if someone has to yell to be heard, it is probably loud enough to cause hearing damage, (Johnson, 2011).
To further evaluate the effects of noise exposure Kujawa and Liberman conducted a study to determine the long-term effects of noise exposure in relation age. They presenting the same amount of 8–16 kHz octave-band noise for 2 hours, measured at 100 dB SPL to a group of mice that varied in age from 4 to 124 weeks. Results indicated two types of permanent hearing loss that occurred. The first was a more immediate response of damaged stereocillia measured by the hearing loss that remained after the temporary threshold shift was resolved and the second was the acquired hearing loss that gradually increased over many years after the exposure. Auditory brainstem response (ABR) and distortion product otoacoustic emissions (DPOAE) results showed that the permanent threshold shift measured at two weeks post expose varied drastically among the young mice (4-8 weeks old) which shifted up to 40 dB SPL and old mice (16- 124 weeks) which did not show a permanent threshold shift at two weeks post exposure (Kujawa and Liberman, 2004).
The long term side effects were evaluated among the different age groups and exposure ages were compared to a control group that was unexposed to excessive noise in order to isolate the damage caused from noise exposure from the effects of hearing loss due to age. The results indicated a correlation between the age when exposed to noise and resulting amount of hearing loss. As exposure age decreased,...