ABSTRACT
INTRODUCTION: The accident of falling from a height is high among construction workers. Construction workers do not use harnesses. Thus, the present study was conducted to identify the factors affecting the non-use of harnesses among construction workers in Tehran, Iran. MATERIALS AND METHODS: In this study was conducted by interviewing professors and construction workers in order to identify factors affecting the non-use of harness. Factors influencing the non-use of safety harnesses were identified from the workers' point of view. The obtained data were classified and coded using MAXQDA 10 software. After that, the most essential, effective and powerful factors were identified using the degree and intersectionality of social network analysis. RESULTS: According to the interview results, 27 factors were determined as factors affecting the non-use of harnesses by construction workers and divided into four main groups. The four groups were harness design, management factors, harness comfort, and attitudinal factors. Based on the results of the degree centrality, the non-ergonomic design and attitude of the harness inefficiency were identified as the most influential and powerful factors. The betweenness indicator also showed that the non-ergonomic design could mediate other factors in the non-use of the harness. CONCLUSION: The findings showed that by considering various factors such as considering more comfort in the design of the ergonomic harness, it produced a better product. Also, the use of safety harnesses by workers increases.
Subject(s)
Construction Industry , Occupational Health , Humans , Iran , AttitudeABSTRACT
Purpose: The present study aimed to design a quantitative tool to evaluate the comfort and usability of working at height safety harnesses. Methods: This cross-sectional study was conducted in both qualitative and quantitative sections in 2022. The research steps included field interviews, an expert panel, and compiling the questionnaires for assessing the comfort and usability of the harness. The items of tools were designed based on the qualitative part of the research and review of the literature. The face and content validity of the instrument were assessed. Its reliability was also evaluated using the test-retest method. Results: Two tools were developed including a comfort questionnaire with 13 questions and a usability questionnaire with 10 questions. The Cronbach's alpha coefficients of these instruments were 0.83 and 0.79, respectively. Additionally, the content and face validity indices were 0.97 and 3.89 for the comfort questionnaire and 0.991 and 4 for the usability questionnaire, respectively. Conclusions: The designed tools showed appropriate validity and reliability and could be used to evaluate the comfort and usability of safety harnesses. On the other hand, the criteria used in the designed tools could be employed in user-centered harness designs.
ABSTRACT
BACKGROUND: Low back pain caused by work, ranked the second after cardiovascular diseases, are among the most common reasons of patients' referral to the physicians in Iran. This study aimed to determine the changes in back compressive force when measuring maximum acceptable weight of lift in Iranian male students. METHODS: This experimental study was conducted in 2015 on 15 young male students were recruited from Tehran University of Medical Science. Each participant performed 18 different lifting tasks involving three lifting frequencies, with three lifting heights, and two box sizes. Each set of experiments was conducted during the 20 min work period using free-style lifting technique. The back compressive force evaluated with hand-calculation back compressive force method. Finally, Pearson correlation test, analysis of variance (ANOVA) and t-test were used for data analysis. RESULTS: The mean of back compressive force (BCF) for the small and large boxes at a frequency of 1lift/min at heights of F - K height, were 1001.02 (±86.74), 1210.57 (±93.77) Ib, respectively. There was a significant difference between mean BCF in terms of frequencies of lifts (P=0.02). The result revealed significant difference between frequencies of 1 lift/min and 6.67 lift/min (P=0.01). There was a significant difference between mean BCF in terms of the sizes of the two boxes (P=0.001). There was a significant relationship between the BCF and maximum acceptable weight of lift in all test conditions (P=0.001). CONCLUSION: BCF is affected by box size, lifting frequency and weight of load.
