Intervensi Ergonomi dalam Kegiatan Pemuatan Log pada Moda Transportasi Ojek Kayu: Pendekatan Biomekanika

Abstract

Pemuatan log secara manual oleh ojek kayu dengan beban log yang melampaui kemampuan pekerja memiliki tingkat risiko yang tinggi pada lumbar spine 5 dan sacral spine 1 (L5/S1), sehingga perlu dilakukan intervensi ergonomi dengan pendekatan biomekanik sebagai upaya pencegahan risiko cedera. Penelitian ini bertujuan menginvestigasi dan menghitung compression force (CF) serta shear force (SF) pada pekerja dan memberikan rekomendasi beban log untuk menghindari risiko Musculoskeletal Disorders (MSDs) akibat kegiatan pemuatan secara manual. Dilakukan analisis biomekanik dan perhitungan Recommended Weight Limit (RWL) pada postur kerja. Data antropometri menggunakan karakteristik asli pekerja (data entry) untuk melihat tingkat risiko aktual yang dialami pekerja. Analisis biomekanik menunjukkan dari 22 postur, 15 diantaranya memiliki nilai CF >3400 N, 1 postur bernilai >6400 N, dan 21 postur kerja bernilai SF >500 N. Postur ekstrem dominan terjadi saat posisi membungkuk dan setengah jongkok yang tergolong tingkat risiko cedera tinggi dengan nilai Lifting Index (LI) >3. Rekomendasi beban log yang dapat diterima pada postur ekstrem memiliki nilai RWL sebesar 10,57 kg dan 11,24 kg dengan nilai LI <1 yakni 0,42 dan 0,45 yang menunjukkan bahwa perbaikan beban angkat mampu menurunkan stres fisik dan dapat menghindari risiko MSDs.

Manual log loading by motorcycle taxi with a log load that exceeds the ability of workers has a high level of risk in lumbar spine 5 and sacral spine 1 (L5/S1), so it is necessary to carry out ergonomic interventions with a biomechanical approach as an effort to prevent the risk of injury. This study aims to investigate and calculate compression force (CF) and shear force (SF) in workers and provide log load recommendations to avoid the risk of Musculoskeletal Disorders (MSDs) due to manual transportation activities. Biomechanical analysis and calculation of Recommended Weight Limit (RWL) on work posture were carried out. Anthropometric data uses the original characteristics of workers (data entry) to see the actual level of risk experienced by workers. Biomechanical analysis showed that of the 22 postures, 15 of them had a value of CF >3400 N, 1 posture had a value of >6400 N, and 21 postures had a value of SF >500 N. Extreme postures predominantly occurred when the bending and semi-squatting positions were classified as having a high level of injury risk with a Lifting Index (LI) value of >3. The recommended acceptable log load in extreme posture has RWL values of 10.57 kg and 11.24 kg with LI values of <1, namely 0.42 and 0.45, which indicates that the improvement of lifting load is able to reduce physical stress and can avoid the risk of MSDs.