In this study, Criteria for common duct reviewed through comparing of other design standards and criteria specifications whether it is for duplication or contradiction. As a result, It was performed to analysis either to move other codes or to be applied as common duct code according to the classified code system.

• 신병길(한국시설안전공단 시설안전연구소) | Shin, Byoung-Gil
• 이유석(한국시설안전공단 시설안전연구소) | Lee, Yu-Seok 교신저자
• 장범수(한국시설안전공단 시설안전연구소) | Chang Buhm-Soo
• 박광순(한국시설안전공단 시설안전연구소) | Park, Kwang-Soon
• 신철식(한국시설안전공단 시설안전연구소) | Shin, Cheol-Slik