The effect of working conditions and gender on human errors in manual assembly line

• Main Author: Leau, Jia Xin
• Format: Thesis
• Language: English; English
• Published: 2015
• Subjects: H Social Sciences (General); HF Commerce
• Online Access: http://eprints.utem.edu.my/id/eprint/16877/1/The%20Effect%20Of%20Working%20Conditions%20And%20Gender%20On%20Human%20Errors%20In%20Manual%20Assembly%20Line.pdf; http://eprints.utem.edu.my/id/eprint/16877/2/The%20effect%20of%20working%20conditions%20and%20gender%20on%20human%20errors%20in%20manual%20assembly%20line.pdf; http://eprints.utem.edu.my/id/eprint/16877/; https://plh.utem.edu.my/cgi-bin/koha/opac-detail.pl?biblionumber=96135

Product defects in an assembly line can happen due to various reasons, and one of the sources is human error. The occurrence of human errors in manual assembly line can be affected by factors, such as workplace condition/environment, equipment and demographics factors. This study adopted two approaches i.e. lab experiment and case study in industry. In the first part, a three-pin plug assembly line was used to simulate the production. The experiment was conducted in the lab to determine the effect of work pace, working conditions, such as working position, jig design, and component bin position, and gender on human errors during manual assembly. The product defects were identified as the occurrence of nonconformance product due to human error. To minimize the sources of defect from other factors, such as working environment, material defects, working experience and equipment failures, these factors were controlled in the experiments to ensure that the defects obtained were solely due to human error. A total of ten participants had participated in this experiment, five adult males and five females. A full-factorial design of experiment was used and there were sixteen combinations of experimental runs in this research. Results showed that there was a linear correlation between work pace and human error. When the production pace increased over the normal, cycle time decreases, causing time pressure condition which had significant effect on human error. Working position had the second greatest effect on human error, followed by gender difference and component bin position. Jig design had no significant effect on human error. Gender difference contributed to the differences in human errors, where females made fewer errors than males in normal pace as well as in the time pressure environment. However, male had faster cycle time than female. Finally, a fitted model which can describe the relationship between human error and working condition parameters was proposed and validated. This model functions as the predictor of human error when the variables of assembly are known. In the second part, a case study was conducted in an electronic company located in Melaka, Malaysia. This company uses an assembly line to produce their products. The case study only focused on the effect of work pace on the occurrence of human errors that lead to product defects. The other variables, such as working position, component bin position, jig design and gender, were not included as they were not applicable in the workplace of the case study. Based on the results, it was observed that the occurrence of human error was higher when production target is increase above the normal capacity. This situation was recognized that there was a time pressure to the workers. In addition, the number of errors also increased as the production target lower than the normal production capacity. The relationship of product defects and production output can be represented using a U-model, where the number of product defects was higher when the production output was lower or higher than the normal production target. This finding was consistent with the experimental results, where time pressure affects the occurrence of human errors.