POCATELLO — One of the three Idaho State University students who were riding in a campus elevator that "unexpectedly descended" five floors on Sunday evening sustained a minor injury, according to school officials.
The incident occurred in Turner Hall, the university’s housing facility for underclassmen, and remains under investigation by ISU and the Idaho Division of Building Safety, ISU spokesman Stuart Summers said during a Monday phone interview.
Summers said the elevator will remain closed until the findings of those investigations are complete.
ISU officials immediately met with all three students involved in the incident and encouraged them to go to either the hospital or ISU Health Center for a medical evaluation. Out of respect to the students involved in the incident, the university would not release their identities, Summers said.
One Turner Hall resident, Luisa Stroppel, who lives on the sixth floor of the building, said that over the weekend the elevator was operating somewhat out of the ordinary. Stroppel said that the elevator stopped, and the LED lights indicated it was on the sixth floor, but the doors remained closed for several minutes, which is much longer than the normal wait of a few seconds. Stroppel was not in the elevator when it unexpectedly descended on Sunday.
The Thyssenkrupp elevator was installed four years ago, according to Summers, who said Thyssenkrupp completes all maintenance and repairs on all elevators installed on the Pocatello campus.
Thyssenkrupp was on campus Monday morning running diagnostics on the elevator, Summers said. He added that on Thursday, Thyssenkrupp serviced the elevator adjacent to the one that descended unexpectedly.
Further, Summers said that Thyssenkrupp is expected to bring a diagnostic expert to thoroughly examine what may have caused the elevator to malfunction.
Though the elevator unexpectedly descended five floors, passing the lobby and stopping at the basement level, Summers said safety equipment inside the shaft worked properly to stop the elevator from free falling. However, he could not comment on the specifics of that system.
Typically, most elevators are equipped with several safety measures to prevent free falls.
The first line of safety measures incorporated into modern day elevators are woven steel cables that most elevator technicians refer to as “ropes.” The number of ropes in a given elevator can range in number from two to eight, with the specific number dependent on something called a factor of safety.
Kim Thompson is an elevator technician with the Idaho Division of Building Safety who inspected the malfunctioning elevator on Monday.
Aside from saying he noticed four or five steel cables, Thompson said he could not comment on the specifics of the elevator safety system until the investigation is complete. Thompson said the elevator was never in an “unsafe condition.”
“Elevators nowadays have so many safety systems installed that it’s almost impossible for an elevator to free fall,” Thompson said.
Elevators also typically have two or three types of brakes. Thompson said that if an error occurs with any of the decoders, a series of computer systems that monitor the elevator’s movements, a clamp closes on the pulley above the car, preventing the elevator from moving.
Unlike an automobile brake, which has to be depressed to engage, the elevator brake is clamped down unless power is supplied to release it. That means that any loss of power, either due to a system error, electrical grid failure or a user-initiated emergency stop request, will set off the motor brake.
Lastly, elevators are equipped with one more fail-safe. A set of counterweights attached on the opposite end of the cables that attach to the elevator car are designed to prevent the elevator from ascending or descending rapidly.
If every other safety system failed and there was only one person in the car, these weights would make the elevator ascend rather than descend. It would happen slowly at first, gaining speed as the ascent continued. A fully loaded car would work in the opposite direction and users inside the elevator would experience a slowly accelerating descent.
Though Thompson could not comment on what safety measure prevented the ISU elevator from dropping to the floor, he said at least one of the measures worked considering the description provided by ISU officials of what the students reported experiencing.
Summers said that all campus elevators undergo annual inspections from the state of Idaho and confirmed the elevator in question had been inspected properly.
“Student safety and the safety of our campus community is our first priority,” Summers said. “We’re grateful that the emergency safety system kicked in and worked exactly how it was designed.”