Layer of Protection Analysis(LOPA) For Semiconductor Cleaning Facility

The semiconductor cleaning process uses various corrosive and toxic chemicals, so there is a risk of safety accidents. in this study, equipment to be evaluated was selected considering the materials handled, safety devices, and operating conditions of the cleaning facility. and than qualitative risk assessment method HAZOP was applied to determine high-risk accident scenarios. based on the derived scenario, layer of protection analysis (LOPA), a quantitative risk assessment method, was performed to review whether current safety measures were appropriate. afterwards, we attempted to determine whether the risk was acceptable and suggest directions for further improvement. HAZOP results showed a high risk of chemical liquid leakage due to corrosion and damage to wastewater pipes and corrosion of baths and chambers. LOAP results confirmed that the sum of the intermediate accident frequencies 1.23×10<SUP>-6</SUP> was within an acceptable range 1×10<SUP>-4</SUP> ~ 1×10<SUP>-6</SUP>. It was confirmed that the frequency of accidents mitigated could be reduced to 3.31×10<SUP>-7</SUP> by taking additional safety measures such as installing a sealing system in pipes at risk of corrosion.