Abstract

Purpose: This study empirically analyzes the electric shock risks caused by the conventional use of molded case circuit breakers (MCCBs) in automatic wheel washers at construction sites and proposes institutional improvements to enhance worker safety. Research design, data and methodology: Field measurements of leakage currents were conducted in control panels of automatic wheel washers at construction sites in Daejeon, Republic of Korea. A TK-61L leakage current clamp meter was employed to verify the hazards of current MCCB installation practices under operational conditions. Results: Despite leakage currents reaching 1.07A (approximately 35 times the lethal threshold for humans) under specific fault conditions, the installed MCCB failed to operate, revealing a critical safety gap in current protection systems. Initial baseline measurements also detected persistent leakage currents of 3.80mA, indicating deteriorating insulation conditions. Conclusions: It is imperative to mandate earth leakage breaker (ELB) installation for wheel washer control panels and strengthen safety certification standards at the manufacturing stage to prevent electric shock accidents. Policy recommendations include revising safety certification requirements, updating construction specifications, and implementing IoT-based monitoring systems.