A study of the noise hazard to employees in local discotheques.
OBJECTIVE
There is growing concern that amplified music in discotheques can cause hearing loss. This study attempts to evaluate the noise hazard of employees exposed to amplified music in our discotheques.


METHODS
Employees comprising of disc jockeys, bartenders, waiters, cashiers and security officers of five selected discotheques were used for the study. Personal noise dosimetry was carried out on 40 employees throughout their workshift. The audiometric examination results of another 46 employees were compared with 37 subjects from a non-exposed match control group.


RESULTS
The range of exposure to noise level above 85 dBA for the employees is 3.6 to 6.9 hours with a mean of 5.1 hours. All the occupational groups are exposed to noise level of at least 89 dBA Leq for their whole work shift. The discotheque group has statistically significant higher prevalence (41.9%) of early sensorineural hearing loss compared to the control group (13.5%). A higher proportion of employees in the older age group (above 30 years old) and working longer (above 1 year) suffer from hearing loss. A significant proportion of the discotheque study subjects (21%) also complained of recurrent tinnitus compared to 2.7% in the control group. The younger (< 30 years) and those with shorter exposure duration (< 1 year) appeared to complain of tinnitus more.


CONCLUSIONS
The study shows that all the employees regardless of occupations are exposed to noise above the permissible level of 85 dBA Leq A high proportion of them also suffer from early sensorineural hearing loss and tinnitus.
Lee
L T
LT
Department of Industrial Health, Ministry of Manpower, Singapore.
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001299:Audiometry; D016022:Case-Control Studies; D005260:Female; D006317:Hearing Loss, Noise-Induced / Q000209:etiology*; D006319:Hearing Loss, Sensorineural / Q000209:etiology; D006801:Humans; D008297:Male; D008452:Maximum Allowable Concentration; D008875:Middle Aged; D009146:Music; D009622:Noise / Q000009:adverse effects*; D009784:Occupational Diseases / Q000209:etiology*; D015995:Prevalence; D012008:Recurrence; D013997:Time Factors; D014012:Tinnitus / Q000209:etiology