MUSCULOSKELETAL DISORDERS WARNING SYSTEM PROTOTYPE DESIGN BY CONSIDERING DOMINANT RISK FACTORS IN CONSTRUCTION WORK

• Main Author: Kusmasari, Wyke
• Format: Dissertations
• Language: Indonesia
• Subjects: Teknik (Rekayasa, enjinering dan kegiatan berkaitan)
• Online Access: https://digilib.itb.ac.id/gdl/view/55592
• Institution: Institut Teknologi Bandung

Construction work has a high risk of musculoskeletal disorders due to physical demands and high work variations, so it is necessary to develop various ergonomic interventions to reduce these risks. Musculoskeletal disorders are one of the company's performance measures in the management of occupational health and safety. Referring to Permenaker no 5/2018, every company must measure and control all ergonomic risk factors. One of the main goals is to reduce the possibility of musculoskeletal disorders in workers. Intervention development needs to consider specific and significant risk factors associated with musculoskeletal disorders to be effective. In previous studies, ergonomic interventions were generally developed based on general risk factors based on the results of ergonomic rapid evaluation methods, such as rapid upper limb assessment (RULA) and rapid entire body assessment (REBA) methods. As a result, the resulting interventions are general and less effective. Based on this, the general objective of this research is to identify specific risk factors related to musculoskeletal disorders in construction work and then design a prototype of ergonomic intervention based on these risk factors. The first stage of this research is to identify risk factors through meta-analysis. The purpose of this meta-analysis is to synthesize the results of previous studies to obtain alternative significant risk factors associated with musculoskeletal disorders. In addition, the meta-analysis method can compare the level of significance of risk factors from various previous studies (either specifically for construction work or similar work). The meta-analysis was carried out by in-depth analysis of various related articles obtained through six search engines (Science Direct, Scopus, IEEE, MEDLINE/Pubmed, Web of Science, Taylor and Francis Online) from 1999 to 2018. The meta-analysis results showed that musculoskeletal symptoms in construction work were associated with individual risk factors (age, body mass index, work experience, physical fitness), physical risk factors (high physical workload, poor working position, lifting heavy objects, vibration), and psychosocial risk factors (psychological workload). The analysis of specific musculoskeletal symptoms showed that 1) significant neck complaints were associated with low job vi satisfaction, 2) significant back complaints related to body rotating position, 3) shoulder and hand complaints were significantly related to age, gender, lifting heavy objects, gripping tools. /small materials, repetitive motions/work, lifting arms above the shoulders, rotating body position, psychological workload, and low job satisfaction, and 4) complaints on thighs and legs are significantly associated with low job satisfaction. The next research stage is a questionnaire survey on construction workers in highrise building projects. The survey aims to identify significant risk indicators related to musculoskeletal disorders in construction workers. Total respondents from the three projects involved were 235 people. The survey instrument was developed from the risk factors obtained based on the meta-analysis results and derived in more detail into various risk indicators. Based on logistic regression calculations, it is known that several significant risk indicators are associated with musculoskeletal symptoms. The indicators are frequency of working in a stooped position, length of work with wrists bent up/down and sideways, duration of lifting arms above shoulders, frequency of moving heavy objects, discomfort with exposure to vibration, working fast, doing a lot of work, and conflicting demands. The survey results show that workers in the lower back mostly feel the prevalence of musculoskeletal complaints during the last 12 months. It was also found that the frequency of working in a stooped position, the duration of raising the arms above the shoulders, and the frequency of repetitive hand movements were associated with lower back complaints. Physical risk indicators related to low back complaints are the basis for developing ergonomics interventions. The third research stage is the development of an ergonomic intervention prototype design. The aim is to obtain a prototype design of an ergonomic intervention that can reduce the possibility of musculoskeletal disorders in construction work. The ergonomic intervention prototype method developed is a system that can warn if the movement of the back, upper arms, and forearms exceeds the predetermined risk limit. Testing the validity and reliability of the angle measurement results was carried out through a laboratory study involving five participants who simulated manual lifting of the material. Participants lifted weights in three height positions that caused the back to bend, and two positions raised the upper and lower arms. In addition to the altitude position, which is the reference for the movement, the participants' movements' tempo is also controlled at a speed of 60 beats per minute (bpm) for ten seconds. The level of validity is tested by comparing the results of angle measurements generated by the application and the motion capture system. The application and motion capture system operate at a frequency of 50 Hz, which means it operates 50 data per second. This application was developed by utilizing a combination of accelerometer, gyroscope, and magnetometer sensors on mobile phones. The motion capture system used as the gold standard is the Vicon Nexus 2.5, which has ten cameras and software to process body angles based on markers placed on participants' body points. The test results show that the application on the system is valid and reliable and can be further developed for other interactive and ongoing physical risk assessments. this study succeeded in mapping various measurable indicators of individual, physical, psychosocial, and occupational risk factors related to multiple musculoskeletal symptoms in construction work. In addition, based on indicators related to complaints in the lower back, a prototype of an ergonomic intervention in the form of a risk warning system was obtained. It is hoped that the developed system can reduce the exposure of risk indicators to complaints on the lower back of construction work in the field.