Incheon Airport becomes first to achieve ACI Level 4 Customer Experience accreditation Primary tabs 1st April 2021 ACI World’s customer experience initiative is currently set out in four stages, with Incheon being the first to reach the top tier Airports Council International (ACI) World has revealed a new level in its ‘Airport Customer Experience Accreditation’ programme, with South Korea’s Incheon Airport being the first to reach the new standard. When ACI launched the programme in 2019, 45 airports signed up to help improve their customer experience management. Incheon Airport was one of a select few to reach level three accredited status last year and has now moved to level four. Accreditation included site verification which begins from level four, which was conducted virtually due to safety restrictions.