Intensity of Sound Research and Public Health

Question: 1) Identify and describe the six main factors that determine the duration and severity of noise-induced hearing loss. 2) Identify and describe three physiologic non-auditory effects of noise. 3) Identify and define three eye disorders and discuss how each is related to the occupational environment. Answer: 1. The six factors that determine the duration and severity of noise-induced hearing loss are identified to be, Firstly, Intensity of sound which is directly proportional to the ear damage. The lowest sound that is audible to the human ear is 0 dB and the highest is 180 Db. Exposure to a high intensity of sound says 85 dB or above for prolonged period may significantly damage hearing (Seidman Standring, 2010). Secondly, Frequency of sound, the measure of a pitch. It is measured in Hertz. The pitch is directly proportional to the frequency of sound. A pitch of about 2000- 4000 Hertz is recognized to cause hearing loss. During the noise induced hearing loss, people cannot hear sound with higher frequencies (Smith et al., 2014). Thirdly, Duration, the length of exposure to noise. Longer the duration of the exposure to noise, the more is the hearing loss. For the unprotected ear, the highest level of the permissible noise per day is 115 dB for 15 minutes. Fourthly, Occupational noise, the sound related to the workplace, say noise exposure in construction sites, Iron and Steel industries (machinery, etc.). Regular exposure to 85 dB or noise level above it is known to cause significant hearing loss gradually (Le Prell et al., 2012). Fifthly, Non-occupational noise, the sound related to community, environmental or residential areas such as noise due to lawn mowers, musical instrument, firecrackers, etc. When exposed on the regular basis, it can directly affect hearing. Lastly, Genetic factors may be responsible for hearing loss, which is gradually manifested with aging. Older people commonly have hearing loss problem; however, it may or may not be due to genetic effect (Smith et al., 2014). 2. Prolonged exposure to noise may cause non-auditory effects in addition to hearing loss such as hypertension, mental health problem, respiration problem, sleeping problem, and muscle stress. The physiologic non-auditory effects of the noise are discussed in subsequent sections. Occupational noises are mainly higher than residential or community noise and mostly cause the non-auditory effects. For example, traffic noise, construction areas, airports. According to Pirrera et al., (2010), exposure to environmental noise, can increase annoyance, results in sleep loss and a causative factor of cardiovascular disease. It is accompanied by hypertension, changes in the pattern of the heartbeat, changes in the diameter of blood vessels especially those in skin, change in blood pressure and changes in heart rate. Patients with cardiovascular diseases are highly susceptible to stroke and hence are recommended to stay indoors or in the environment with little noise. Experimental studies conducted by Basner et al., (2014) in laboratory conditions showed that continuous exposure to noise disturbs the Mental health. It decreases the ability to sustain attention. It is associated with the increase in annoyance and stress, with constant exposure to high level of noise. Researchers thus believe noise as "non-specific stressor" that disrupts mental health. Literature research provides evidence of the sleeping disorder that is Insomnia resulting due to noise exposure for prolonged period. Loss of sleep may be caused by disturbed nerve cells, increased muscle tension and changes in respiratory reflexes. Muscle tension occurs due to loud noise. Muscles burst into activities by more contraction for protecting the body from exposure to loud noise. Similarly, loud noise tends to alter the respiratory rhythms (Le Prell et al., 2012). 3. Several eye disorders have been identified that arise due to a workplace environment. For example, IT professionals spend more time in front of the computers developing myopia or hypermetropia. Workers with the high level of eye injuries include those working in construction sites, chemical industries, and other manufacturing services. The primary eye disorders related to the occupational environment are: Firstly, Low vision, people may not be able to see objects that are near to eye or at long distance. The former is called shortsightedness, and the later is called long sightedness. The increase in eye pressure changes the size of eye-lenses. People who are mainly vulnerable to low vision problem include IT professionals, teachers, drivers, tailors, carpenters, etc. This kind of work requires high focus thus gradually affecting the eyes over time. In several cases, low vision gradually leads to blindness (Liu et al., 2013). Secondly, Chemical eye burn, employees in Chemical industries is exposed to harmful substances that may be toxic in nature. The severity of the eye injury depends on the pH of the chemical. Early signs of chemical burn include pain, irritation, tearing, and redness, swelling of the eyelids and blurred vision. Delay of treatment in case of the acid or alkali burn may cause permanent vision impairment, glaucoma, and cataract (Berger et al., 2013). Surgeries may not always be successful in the delay of treatment causing permanent damage to vision. Thirdly, Conjunctivitis, characterized by the redness of eyes and severe inflammation. The causative factors are the virus, pollutants, pollens, smoke, etc. It occurs mainly in workers dealing with pesticides, fertilizers, gardeners, factories having machines, which produce the significant amount of smoke. As the employees work bare eyes, they are highly vulnerable to such infections (Smedley et al., 2013). References Basner, M., Babisch, W., Davis, A., Brink, M., Clark, C., Janssen, S., Stansfeld, S. (2014). Auditory and non-auditory effects of noise on health.The Lancet,383(9925), 1325-1332. Berger, S., McAteer, J., Schreier, K., Kaldenberg, J. (2013). Occupational therapy interventions to improve leisure and social participation for older adults with low vision: A systematic review.American Journal of Occupational Therapy,67(3), 303-311. Le Prell, C. G., Henderson, D., Fay, R. R., Popper, A. N. (2012).Noise-Induced Hearing Loss. Springer. Liu, C. J., Brost, M. A., Horton, V. E., Kenyon, S. B., Mears, K. E. (2013). Occupational therapy interventions to improve performance of daily activities at home for older adults with low vision: A systematic review.American Journal of Occupational Therapy,67(3), 279-287. Pirrera, S., De Valck, E., Cluydts, R. (2010). Nocturnal road traffic noise: A review on its assessment and consequences on sleep and health.Environment international,36(5), 492-498. Seidman, M. D., Standring, R. T. (2010). Noise and quality of life.International journal of environmental research and public health,7(10), 3730-3738. Smedley, J., Dick, F., Sadhra, S. (Eds.). (2013).Oxford handbook of occupational health. OUP Oxford. Smith, R. J., Shearer, A. E., Hildebrand, M. S., Van Camp, G. (2014). Deafness and hereditary hearing loss overview.