Click here for more articles by Kormedi.com. The full-group comeback of K-pop phenomenon BTS at Seoul's Gwanghwamun Square is drawing global attention to Korea. More than 260,000 people are expected to gather at the iconic spot in the Korean capital this Saturday. To ensure public saftey, the police and the Seoul Metropolitan Government plan to control access to 31 nearby buildings to prevent overcrowding. In places where large crowds gather, special caution is needed to avoid crowd crush incidents. Why do crowd crush incidents occur? First, let’s look at why crowd crush incidents happen. A crowd crush refers to death caused by pressure. When a large number of people gather in a confined space, the pressure exerted on each individual increases. In particular, if excessive pressure is applied to the chest, it can lead to rib fractures or oxygen deprivation. When oxygen supply decreases, brain activity stops. An adult consumes about 0.2 to 0.3 liters of oxygen per minute, with the brain using the most amount. If deprived of oxygen for two minutes, cerebral cortex cells begin to be damaged.