ABSTRACT
Using audiometric test data, noise exposed workers were followed up to assess the activities for hearing conservation from 1989 to 1992. The subjects of study were 71 workers who could be followed up at least two years during this follow-up period. In all subjects, increasing trend of hearing threshold levels (HTLs) was observed after three years of follow-up at all testing frequencies in audiometry and this increase was statistically significant at 8KHz(p<0.05). Also, HTLs increased significantly(p<0.05) in the workers who complained tinnitus(at 0.25, 8KHz), who ws below 90 dB (at 8KHz). Effectiveness of the activities for hearing conservation, assessed by sequential test-retest comparisons, was lower in the workers who complained tinnitus, who had past history of ear disease, and whose workplace noise level was below 90 dB. These findings suggest that the activities for hearing conservation at workplace may have been unsatisfactory until now and more stringent measures may be necessary, especially in the workers who complain tinnitus, who have past history of ear disease, and whose workplace noise level is below 90dB.
Subject(s)
Audiometry , Ear Diseases , Follow-Up Studies , Hearing , Noise , TinnitusABSTRACT
This survey was performed to obtain the basic information for the prevention and management of occupational low back injury(LBI). The subjects of this survey were 952 workers(male, 892;female, 60) who had taken occupational LBI in some industries of Pusan area from January 1 to December 31, 1991. Observation period was 2.6 years from the beginning to the end of medical treatment. The obtained results were summarized as follows; 1. The proportion of LBI workers was 15.9% of the workers who had taken any occupational injuries and 0.32% of all workers in this surveyed area. 2. 8.0% of the workers had taken LBI on the 1st day of employment and 55.2% of the workers were within one year, 91.4% of the workers were within 10 years according to cumulative frequency distribution. 3. Handling of heavy objects was the most common cause of LBI(32.0%) and fall down(26.9%) and slip down(16.3%) were the next in order. 4. The most common causes of both lumbar sprain and HNP were handling of heavy objects and that of lumbar fracture was fall down. 5. The mean duration for medical treatment of LBI workers was 143 days. 6. The total direct compensation cost for LBI workers was 6,736 million Won and the proportion of medical, resting, disability compensation costs were 25.0%, 37.0%, 38.0% respectively. 7. The percentages of retreated workers and disabled workers were 11.9%(113 persons) and 22.9%(218 persons) of total LBI workers respectively.