12th April 2015
Most people accessing high-rise buildings know not to use the lifts in the event of a fire alarm. However, recent studies and research in New York have been looking at the possibility of occupant-evacuation lifts that can be used in these circumstances. The installation of these systems could improve the efficiency and safety of evacuation procedures.
Traditional Evacuation Procedures
For decades, workers and those living in skyscrapers have been under the impression that emergency stairs are the best ways of exiting the building if a fire starts. We see it as the safest method, and there are numerous signs around lifts telling us not to use them during an emergency.
Originally, lifts were available for use in the event of a fire. However, during the 1970s some people became trapped in fires after using the lifts when shafts filled with smoke or they exited the lift on a floor containing the fire. By the end of the decade, lifts would automatically go to the ground and go out of service if an alarm system activated or it detected smoke.
It has now become standard for lifts not to be used in emergencies. However, as buildings become taller, more populated and a greater target for terrorist threats, we need to look at changing the evacuation procedures. The use of lifts could be the best way to exit a high-rise building safely and quickly.
There is also the issue of meeting accessibility requirements for disabled people and others with access issues. These groups of people use the lifts to get into a building, and they also require a way of getting out safely. There were a number of issues raised during the 2001 World Trade Center attacks, with many older people and those who were overweight or pregnant struggling to use the stairs. In fact, many of those in the second tower who escaped did so by using the lifts.
Safe to Use the Lifts
In some of the highest skyscrapers across the globe, especially those over 420 feet, it is not always practical for occupants to safely exit in an emergency using just the stairwells. These can become crowded and cause panic to break out. On the other hand, occupant-evacuation lifts can quickly take people from a dangerous level to somewhere that is safer. From here they can either exit the building if possible or wait to be rescued by the fire service.
Standard lifts are still not advisable in an emergency, so many new buildings have occupant-evacuation lifts in the plans or adaptations can be made to bring the usual lifts up to the right standards. There are a number of additional features that need to be included to ensure they meet the necessary requirements. These include reinforced walls, changes to the emergency generators to prevent them switching off and raised floors to protect the shafts from water released by sprinkler systems or hoses.
With these systems in place, evacuation procedures should become more efficient. It might become possible for people to use lifts during emergencies. However, work will be needed to gain the trust of workers and residents, who have become used to being told they are dangerous to use if a fire breaks out.