New technologies and safety features being developed to improve performance
July 25, 2023
July 25, 2023
Statistically speaking, elevators and escalators are the world’s safest forms of transportation. In the United States alone, riders travel around 2.8 billion miles per year, and yet their accident rates are better than planes, trains or automobiles. Still, there are threats to riders out there. “Safe” can always be made “safer”. Every generation of elevators and escalators sees new leaps forward in safety—and this generation is no exception.
Hard-learned lessons learned in the past two decades guide the latest developments in elevator safety:
Disasters such as the September 11, 2001 attacks made it clear that the industry needed to rethink how passengers use elevators in an emergency. The answer couldn’t just be “wider stairwells.” No matter how carefully planned an evacuation may be, only so many people could fit in a stairwell at once. Evacuating every passenger via elevator was not an ideal solution, either.
Hence, the development of occupant evacuation operations (OEO). Engineers recognized that, while evacuating an entire building using elevators was unfeasible, they could provide more options for the most at-risk occupants in the building.
Today, many buildings under construction are built with OEO systems in place. Other elevators can be retrofitted with simple kits. With OEO systems, riders move to the nearest safe egress point, from which they can take the stairs—keeping evacuation operations as efficient as possible while freeing up the elevators for emergency services personnel.
The flip side of OEO is firefighters’ emergency operations (FEO). FEO systems are activated by fire alarm-initiating devices and operate in two phases. In the first phase, the elevator proceeds to the nearest designated egress point. Once passengers have safely evacuated, the second phase begins. The elevator locks out anyone other than firefighters and other designated emergency personnel. This allows firefighters to bring equipment to—and evacuate trapped occupants from—floors at risk as efficiently as possible.
Fires and damaged buildings aren’t the only risks, as operators learned during heavy floods caused by Hurricane Sandy in the northeast and Hurricane Harvey in Houston, Texas. During these hurricanes, there were few solutions in place to prevent elevators from sinking into flooded shafts—or to protect elevator shafts from flooding in the first place.
After the disasters, the American Society of Civil Engineers (ASCE) published the Flood Resistant Design and Construction design standard, also known as ASCE 24, which provides guidelines and requirements for buildings in flood-prone areas. Buildings designed according to ASCE 24’s specifications (including the elevator shafts) are more likely to withstand heavy flood loads and flood damage. And in the event of a disaster, the code mandates that elevators in those buildings are programmed not to descend into floodwaters. Passengers in a flooded building may find themselves inconvenienced—but they won’t get their feet wet.
Right now, an ASME working group is developing even more prescriptive requirements to further guarantee safety during flooding. Any resulting provisions should work effectively with other safety systems in place (such as OEO and FEO, or seismic sensors).
Revisions to building regulations don’t stop at ASCE 24. Codes now contain provisions to protect passengers against smoke, fire or water entering the elevator’s hoistway. Emergency power is also mandatory in many areas. So is real-time messaging sent to operators (and, in some cases, displayed in the elevators themselves) in order to show an elevator’s status and its maintenance needs.
Whether due to lightning, grid problems, or other causes, voltage spikes and power outages are a fact of life in elevator and escalator operations. Rare as they may be, outages do happen. Now, more and more elevators compensate with standby power systems, ensuring that a loss of power doesn’t cause a dead stop or a loss of communication with the outside world. The standby power systems also mean emergency services can still use the elevators, too.
For an example of this in action, consider the ADAMS Anti-Personnel Entrapment System. In the event of a power loss, the battery-powered system keeps communication lines open while automatically moving passengers to the nearest point of egress. All without any need for emergency assistance.
The latest advances in software and hardware allow modern elevators (and retrofitted older ones) to detect and protect passengers in a variety of situations. Sometimes, that means ensuring the doors don’t close until everyone is inside, a task performed by the ADAMS CabSafe system. It combines a light curtain, time-of-flight sensor and controller working in tandem to keep elevator doors open until every last rider has entered. Other times, devices such as the Safe-T-Lock monitor doors for faults and stop the elevator in its tracks until it can ensure the doors are closed. It may even mean analyzing usage data in real-time via advanced software, allowing operators to predict when maintenance is necessary. That lengthens the life of equipment, minimizes downtime and maximizes safe operations.
This technology extends to escalators, as well. Step motion safety devices will stop the escalator if an object is trapped between the steps or step and skirt brush, like the ADAMS SafeyStrip brushes.
Not all of these features are guaranteed to be available in your equipment. Escalators and elevators can have long service lives, so new features may not be installed. Local ordinances may not require certain standards. Building owners may be dragging their feet on making necessary upgrades. But adding features via a retrofitting kit is almost always an option—so operators should always be on the lookout for new solutions they can incorporate into their equipment.
Remember, no form of transportation is without risk, but elevators and escalators are only getting safer!