I live in a Korean apartment building and I am not sure what to do in case of a fire?

Korean apartment buildings, especially anything built after 2005, have detailed fire safety systems but the procedures aren't intuitive if you've never been briefed. Every floor has a fire alarm bell (화재경보기), automatic sprinklers in hallways and inside units, smoke detectors, and emergency exit signs in green. Each apartment also has a built-in standpipe and most balconies have a partition wall (경량칸막이) you can break through to your neighbor's balcony in case the corridor is blocked, plus a downward escape ladder (완강기) hidden in a small box near the window in many units.

If the alarm sounds, don't take the elevator. Touch your apartment door first to feel for heat, and if cool, exit calmly down the stairs to the ground floor or rooftop, depending on which is closer to clear air. If the corridor is smoky, stay in your unit, wet towels, seal the door gap with them, and call 119 with your address and floor. The 119 service has English interpretation available 24/7, just say "English please" and they'll connect you. Most buildings hold mandatory fire drills twice a year (소방훈련), which are worth attending. Check that your apartment's escape ladder still works (some get rusted shut over time) and that your detector batteries are fresh. The free Smart 119 app sends fire status updates and lets you alert emergency services with your GPS location.