This study aims to examine the validity of current environmental safety standards and propose necessary improvements to minimize health risks posed by heavy metals in children’s activity zones. Compared to adults, children are more vulnerable to hazardous substances, and exposure to heavy metals can severely impact their neurological development and physical growth. In Korea, the amendment of the Enforcement Rules of the Environmental Health Act (Annex 4-20) in July 2021 reduced the acceptable threshold for lead (Pb) in paints and finishing materials used in children’s activity zones. However, regulatory standards for other heavy metals remain insufficient. Therefore, this research investigates and analyzes both domestic and international standards for heavy metals in commonly used materials such as wallpaper, flooring, finishing materials, and paints. This paper proposes guidelines for improving current regulatory criteria based on scientific validity and potential exposure. The findings are expected to serve as foundational data for advancing proactive environmental safety management strategies to better protect children’s health.