The accident happened so fast that by the time authorities responded at 9:10 a.m. to the school's Foundation Building, it was too late.
A witness said the elevator was stuck between floors and gave way as the woman was climbing out.
"When the doors opened, the floor was not in the right place, so she decided to try to get out of the elevator, and it moved, and that's when she became trapped," said Toni Beron, a university spokesperson.
The woman, identified as 48-year-old Annette Lujan, a university employee, was declared dead at the scene.
Long Beach Fire Capt. Rich Brandt confirmed the elevator dropped as Lujan was trying to climb onto the third floor, wedging her between the elevator and the shaft. It took an urban search-and-rescue team more than an hour to remove the body.
"It was a very delicate operation between moving the elevator and the body at the same time," Brandt said.
Lujan was using the only working elevator in the three-story building. A second elevator had been closed for maintenance.
Campus police closed the building to conduct an investigation. The university called in a crisis counselor and told employees to go home for the day.
"People here are absolutely devastated," Beron said. "She was known by a lot of people in this building."
For anyone who is ever caught in a similar situation, Brandt said the best thing to do it to sit down and remain calm.
"These are mechanical pieces of equipment. They don't care about human life," he said.