ABSTRACT

Cassava processors currently using traditional processing technology are faced with the problem of exposure to musculoskeletal discomfort among other health hazards due to the sieve aperture and posture adopted during the sieving process. This research is focused on evaluating the effects ergonomic intervention and sieve aperture modification have on musculoskeletal discomfort of processors during dewatered cassava mash sieving process. To this end, the following were carried out: survey of availability of improved and motorized sieve, measurement of traditional sieve aperture, survey of knowledge of effect of sieve aperture modification, determination of level of exposure of processors to work — related musculoskeletal discomfort, experimentation and establishment of best fit sieve aperture, determination of anthropometric characteristics of cassava processors. These were factored into the design and development of improved manual and motorized Dewatered Cassava Mash (DCM) sieve as a means of intervention on discomfort level of processors during sieving process. To accomplish these, questionnaires were administered to one hundred and fifty (150) processing centres and respondents to elicit response on available sieving technology, measurement of ninety (90) traditional sieves to ascertain prevailing aperture, use of one hundred and eight (108), 15 item questionnaires administered to randomly selected processors to elicit response on background knowledge of sieve development, experimentally modifying sieve aperture by means of perforated method using drill bits, ,measurement of processors body parts for use in the development of improved and motorized sieve and evaluation of effects of intervention of the developed sieve on musculoskeletal discomfort. Results of data collected and analysis showed that there is no improved manual sieving machine in the study area. The 2% motorized sieves observed were not functional. There is prevalent use of approximately 3mm sieve aperture arbitrarily fixed by the local developers and this combined with awkward posture used by the processors during sieving process, expose the processors to a high level of work related musculoskeletal discomfort (WMSD) of 66% quick ergonomic checklist (QEC) rating. Experimentally established sieve aperture of 6mm was seen to increase throughput capacity from 35.3 ± 3.30 kg/hr obtained from the locally made sieve to 66 ± 6.02 kg/hr and by incorporating this to an ergonomically developed improved sieve resulted in the reduction of processors exposure to WMSD from 66% to 47%. A second intervention utilizing motorized-modified sieve and designed with ergonomics was very effective, while increasing the throughput capacity from 66 ± 6.02 kg/hr to 491 ± 5.24 kg/hr, processors' exposure to WMSD was reduced to an acceptable limit as low as 26%. Processors should be educated to be aware of the level to which they are exposed to WMSD while using the traditional sieve and change to the improved method as soon as possible.