The 5S audit is known as troublesome as it evaluates how the 5S practice is implemented on the shopfloor with respect to thousands of continuous improvements. This study applies a novel sustainable benchmarking framework that assists practitioners in understanding their current position and to make continuous improvements with priority on the self-assessment of a 5S audit for a semiconductor fabrication plant (fab). This study applies the novel 5S-Failure Modes and Effects Analysis (5S-FMEA) framework to categorize findings in the 5S audit and subsequently justify the 5S-Risk Priority Number (5S-RPN) for a fab. The self-assessment result for a 5S audit can be transformed from qualitative statement into a quantitative evaluation to examine and prioritize all descriptive failure modes (findings) on a 5S audit. Practitioners can stepwise apply the proposed 5S-FMEA and 5S-RPN to their self-assessment of a 5S audit in a closed-loop Plan-Do-Check-Act (PDCA) cycle. This is the first attempt to evaluate (check) and prioritize (act) descriptive failure modes (findings) of 5S-FMEA using the quantitative approach of the 5S-RPN for semiconductor manufacturing. A case study demonstrates the feasibility and robustness of the proposed model.