In Bangladesh economy, RMG sector plays a vital role. From the last decade, RMG sector becomes popular in Bangladesh and it contributes to the national economy in considerable rate. It is necessary to focus on quality control of garment industry [1] [2] [3] . Cho & Kang (2001) showed that quality control in the garment industry is a big challenge for existing and it maintained from the initial stage to the stage of final finished garment [4] . In this industry, product quality can be calculated by different kind of scale. These are quality and standard of fibers, fabric construction, yarn, surface designs, color fastness and the final finished garment products [5] . Number of defected occurrence and percentage of defected product are very common way to calculate product quality.

This research has shown that the major departments of a garment manufacturing industry are cutting section, sewing section, finishing section. After finishing of the cutting operation garments components, all the garments parts are joined and sewn as sequentially. In this research, defects of sewing operations for ladies’ tops and trousers are discussed. Rahman & Amin and Talapatra & Rahman (2016) have mentioned that defect is the common term in the garment industry. Defect is the loss of time, cost and raw material [6] [7] . So, it is a burning question for manufacturer about how to reduce defects. This research has used DMAIC methodology to reduce defects of RMG that is used which is a problem solving of Six Sigma. The Six Sigma is a philosophy that is used to reduce defects. Nupur, Gandhi, Solanki & Jha (2018) implemented six sigma in cutting process of apparel industry where (DMAIC) approach has been followed to solve the underlying problem of reducing defects and improving sigma level through continuous improvement process [8] . Nagi & Altaraz (2017) also used six sigma DMAIC approach to implement lean tools and facilities layout techniques to reduce the occurrence of different types of nonconformities in the carpeting process [9] .

The DMAIC method follows a conductive five-step: Define, Measure, Analyze, Improve and Control necessary to obtain reliable results. According to Brundage, Kulvatunyou, Ademujimi & Rakshith (2017), the DMAIC approach of Six Sigma works as a filter to pass from a complex problem with many uncontrolled variables to a situation where quality is controlled [10] .

This research has identified all the defects in the sewing department of FCI (BD) LTD and applies DMAIC methodology to reduce the defects and this analysis is arranged by research methodology in Section 2 by the following steps: Define, Measure, Analyze, Improve and Control Phase and Conclusion is in Section 3.

For garment item, i.e. ladies’ tops and trousers, data sheets were collected for the length of one month (January). The end line quality inspectors provided the data sheets from their record books from the production lines of the sewing section of FCI (BD) LTD when we visited the garments factory. 15,472 ladies’ tops and trousers were examined and we found 1806 defective pieces. Our main purpose was to identify the top most defects, the root cause of the defects, give some suggestions to reduce the percent of defects and improve sigma level. DMAIC methodology is used for this purpose. It can be illustrated with the following.

Define: problem selection and benefit analysis. Identifying and mapping relevant processes, identifying stakeholders, prioritizing customer needs & making a business case for the project.

Measure: translation of the problem into a measurable form, and measurement of the current situation.

Analyze: identification of influence factors and causes, identifying potential influence factors & selecting the vital few influence factors.

Improve: design and implementation of adjustments to the process to improve the performance & conduct pilot test of improvement actions.

Control: empirical verification of the project’s results and adjustment of the process management and control system in order that improvements are sustainable, the new process capability & implement control plans.

The aim of this research is to reduce the defect of products and to improve quality. To minimize the defects of garment products DMAIC methodology has been used. In this method, at first problems were identified. We have been focused on sewing section and found out sewing defects. Pareto chart is used to show sewing defects for experimental lot. The percentage of defects from total product is also calculated. Define phase shows that defected piece is 1806 in 15,472 pieces. The percentage of defect was 11.67%. The range is not in tolerable range. For given solution, control phase shows that defect percentage is reduced to 9.72%. To justify the given solution, sigma level is used. In the past, sigma level was 2.69. After Improve phase, it has been upgraded to 2.8. This research has focused some preventive solutions from other researches and also showed that creation of awareness among the stakeholders of a garments industry has decreased the occurrences in a sewing line day by day. This will create a positive effect on the management and will also help to minimize the defective percentage (%) in a

sewing line of a garment industry. The limitations of this study are that: it was concentrated only on one garment industry and only for sewing section, and only one sewing line was focused, and calculation had been done for two products. But the significance of this research is that this study can help in minimizing the other sections in garments industry. Other researchers can also use this procedure to reduce defect rate in other manufacturing industries. Finally, reduction of defect rate improves quality and apparently, improvement of quality will give a positive impact in RMG sector.

Zaman, D.M. and Zerin, N.H. (2017) Applying DMAIC Methodology to Reduce Defects of Sewing Section in RMG: A Case Study. American Journal of Industrial and Business Management, 7, 1320-1329. https://doi.org/10.4236/ajibm.2017.712093