Seoul National University
He is a professor and vice president of the graduate school of public health, Seoul National University. Also, He serves as a vice president of Korean Industrial Hygiene Association and associate editor of the international Journal, Safety and Health at Work. He published more than 150 peer reviewed papers. His major research area included exposure assessment at the workplace and indoor environment covering wide range of hazardous agents from chemical, physical agent to bioaerosols. Recently, his research area includes nanomaterial assessment and exposure assessment of hazardous agents at the semiconductor industry.