Purpose: This study experimentally verified the effectiveness of an improved Tool Box Meeting (TBM) delivery system designed to mitigate safety risks stemming from language barriers among foreign construction workers. Research design, data and methodology: Involving 120 workers across five sites, the experimental group received a four-week intervention featuring native language support, pictograms, and designated safety leaders, while the control group received standard Korean-based verbal instruction. Results: Independent samples t-test analysis revealed that the experimental group demonstrated statistically significant improvements compared to the control group in understanding of safety knowledge (t = 5.42, p < .001), safety practice behavior (t = 4.89, p < .001), and TBM satisfaction (t = 6.13, p < .001). The intervention effect was most pronounced in satisfaction (Cohen’s d = 1.50), with Vietnamese workers exhibiting the most positive outcomes. Conclusions: These findings provide empirical evidence that integrating visual and linguistic support into TBMs meaningfully enhances safety compliance and understanding. The study concludes that the construction industry should adopt nationality-tailored TBM processes, supported by multilingual content and on-site safety leaders, to ensure effective safety management for a diverse workforce