Abstract:
The problem of industrial noise around Addis Ababa was examined in this study. Noise
measurement and survey was carried out at four factories (two textile and two metal
processing) to assess the magnitude of occupational noise exposures of workers. A
sample of 200 workers were selected randomly from each department and surveyed with
questionnaires in order to determine the status of the working environment and safety
practices at work. Parallel to this, measurement of occupational noise levels at the
respective departments were done using digital sound level meter ( Bruel and Kjaer SL-
4001model) that meets IEC 651 type 2. The highest noise levels were documented in the
planner machine room in the wood workshop unit and in the heat treatment sections (in
the foundry department) of the Akaki Spare Part Share Company. The noise
measurement also confirmed that out of the total 42 working sites surveyed, 24 of them
(57.1%) prevailed significantly higher noise levels than NIOSH Recommended Exposure
Levels(REL). All of the 19 working sites (100 %) in the metal processing factories and
only five of the working stations out of twenty three (21.74 %) in the textile
manufacturing factories fall under this category. This study also confirmed that 26.2% of
working environments in these factories showed noise levels which exceed the
Permissible Exposure Level (PEL) of 90dB(A) for eight hour exposure stipulated by
OSHA and ILO. This group represents 4.35 % and 52.63 % of the surveyed working sites
in the textile and metal processing factories respectively. The questionnaire and interview
survey showed that only 23.8% of workers under noisy occupational environments were
wearing HPDs (hearing protection devises). Thus, the study demonstrated that due to
high noise levels of the occupational environments, especially in the metal processing
factories, workers are exposed to a high risk of noise induced hearing loss and
associated health threats. With regard to this, a hearing conservation program (HCP),
which is a recognized method of preventing noise induced hearing loss in the
occupational environment, is recommended to be implemented urgently in all the
factories.
Key words: Occupational noise, Hearing Conservation Program, Hearing Protection
Devises.