Controlling the quality of PDAM drinking water production using the MEWMA Bayesian control chart

The provision of drinking water for the people of Indonesia is managed by the Regional Drinking Water Company or PDAM. In order for the quality of the water distributed to meet the quality standards, it is very important for PDAM to carry out periodic water quality control for each of its characteristics. The characteristics of water quality taken in this study are physical and organic chemical characteristics while the quality control process uses the MEWMA control chart. The MEWMA control chart is a control chart that can identify very small average shifts, so that in water quality control research the MEWMA control chart is often used. The development of the use of the Bayesian method on the control chart can improve better process monitoring. So the Bayesian method was added to the use of the MEWMA control chart to produce a Bayesian MEWMA control chart that has a higher level of sensitivity compared to classical MEWMA. After the study was conducted, the results of the Bayesian MEWMA control chart with a weighting value (λ) of 0.1 were obtained, which was the most optimal with the ARL value of the Bayesian MEWMA control chart on the physical criteria of 10.8256 and on the chemical criteria of 13.3979, which means that the performance of the Bayesian MEWMA control chart works well.