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Virtually, detection of shifts in the dispersion parameter of the process is more valuable before monitoring the location parameter of the process. For the monitoring of the dispersion parameter, the S² chart is a common choice in the literature. In this paper, we proposed a modified S² chart based on modified successive sampling, which is cost effective relative to simple random sampling. The run length properties are used as comparative measure and the findings depict that all proposed schemes outperform the classical S² chart. Finally, the application of the proposed scheme is demonstrated using a real-life engineering process.