When a fire breaks out in a high-rise building, conventional wisdom is that stairwells are the only way out. Lifts are verboten in such scenarios, while sheer height typically prevents any other viable route of egress from tall modern buildings. If the stairs are impassable, or you can’t reach them, you’re in dire peril.

In South Korea, though, there’s another option for escape. The answer involves strapping on a harness and descending down ropes hanging off the side of the building, just like in an action movie. It might sound terrifying, but these descending lifeline devices have become a common part of fire safety infrastructure across the country.

Going Down

The concept is elegantly simple—tall buildings like apartments and hotels feature compact rope escape devices that can be quickly deployed from windows or balconies. These allow people to control their descent down the exterior of a building in the event that there is no other route of escape. While fleeing a building down a rope is typically the preserve of fictional spies or trained climbers, these carefully engineered systems are designed for use by ordinary people in emergency situations.

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The typical Korean descending lifeline comes as a kit with some simple components. It consists of a rope or cable, a friction-based descent control mechanism, and a harness system that can be donned quickly by sliding under the arms and tightening a strap. Deploying the device is relatively simple. The rope reel is attached to a large deployable hook that is firmly mounted to the building’s wall, using a screw-threaded coupling. The rope is then thrown out the window. At this point, the user merely needs to attach the harness and tighten it prior to leaving the building.
A typical lifeline descent kit, manufactured by Kfire. Credit: Kfire
When exiting the window, the user is instructed to face the wall on the way down, using their hands and/or feet to control the descent. Ultimately, though, the mechanical speed regulator ensures a safe pace of descent. The devices only allow the descent of one person at at time. However, each end of the rope has a harness. Thus, when one user has descended to ground level, the next person can grab the harness at the other end which has ascended to the window, and begin their descent. This can continue for as many people as needed.

Key to these devices is their focus on simplicity. The descent control mechanism uses a geared braking system that automatically limit the speed of descent to 1.5 meters/sec or less, preventing the user from descending too quickly even if they panic and release their grip. The lifelines are also sold in a range of different lengths to suit the heights of individual floors in a building. This is important to ensure that as the user hits the ground, the other end of the rope has carried the other harness back up to the floor for the next user. The longest variants typically sold are 45 meters in length, intended for buildings up to 15 stories tall. Limits of practicality mean that while these lifelines are useful for many buildings, they’re perhaps not applicable to taller skyscrapers where such escape would be more difficult.

The engineering challenge here isn’t just mechanical. Automatic rope descent systems are a well understood technology, as are hooks and brackets rated to carry human weight for climbing or otherwise. The real challenge comes down to human factors—in that these systems need to be something people can figure out how to use under conditions of extreme stress. The devices need to be intuitive enough that someone who has never used one before can figure it out while a fire rages behind them. It’s one thing to learn how to use a rope descent system by watching a video and trying the equipment at a calm training session. It’s another thing entirely to do so while a fire rages in the hotel hallway behind you.

While these lifeline systems are relatively simple, they’re still a lot more complicated to use than something like an airliner life jacket. Requiring an inexperienced end user to thread a fitting on a rope coupler without dropping it out the window in a panic situation is a tall ask. Still, the lifelines provide a useful additional escape option. It may not be the easiest way out of the building, or anybody’s first choice, but when there’s no other option, it’s good to have.

South Korea’s adoption of these systems reflects both the country’s high-rise-heavy urban landscape and a pragmatic approach to disaster preparedness. Many apartment buildings and hotels are now required to have these devices installed. The devices are typically mounted in weatherproof boxes near windows or on balconies, ready for deployment when traditional escape routes are compromised. In some cases, the rugged boxes the lifelines come in can even be used as a step-up to ease egress out of higher windows.

Perhaps most importantly, these systems represent a shift in traditional thinking about fire safety. In most jurisdictions, the idea of asking average people to belay down a building is considered untenable—too dangerous and too complicated. In South Korea, the lifelines are on hand, and put control back in the hands of building occupants. When every second counts and traditional escape routes have failed, having a lifeline system could mean the difference between life and death. It’s a sobering reminder that sometimes the best high-tech solution is one that lets people save themselves.