Emergency personnel gather outside of a building where there was an elevator accident in New York, Wednesday, Dec. 14, 2011. (Photo credit: Seth Wenig/AP Photo)

Investigators looking into a fatal elevator accident in New York revealed today that the maintenance workers had been performing work on the elevator hours before it crushed 41-year-old Suzanne Hart on her way to work.

"Workers from Transel were performing electrical maintenance work on the elevator involved in the accident hours before it malfunctioned,"  Tony Sclafani, the chief spokesman for the New York City Department of Building, told ABCNews.com.

When ABCNews.com contacted Transel on Wednesday, Robert Pitney, a director, said he was "not in a position to make any comment," as it was "too premature."

"This work has now become the focus of our investigation," Sclafani said. "We're going to review their maintenance protocol. We will be asking for a list of their clients in the city and, over the next few weeks, our inspectors will plan on conducting a sweep of these elevators."

The building, 285 Madison Avenue, has voluntarily closed for Thursday and Friday while all 13 of the building's elevators are inspected, Sclafani said.

"The force of the accident has raised some potential structural concerns for the building and our engineers are conducting a review," he said.

On Wednesday, Hart was killed when the elevator unexpectedly rose as she was stepping in, crushing her between the elevator and the shaft wall.

Hart was the director of new business, content and experience at ad the company Young & Rubicam, according to her LinkedIn page.

Hart was on the first floor and heading to work around 10 a.m. at 285 Madison Ave., between 40th and 41st streets. The doors closed on the Hart as she entered the elevator and it pulled her upward into the shaft.

Two other passengers in the elevator were treated for trauma after witnessing the  accident.

The cause of the elevator malfunction was not immediately determined.

Elevator inspection records from New York's Department of Buildings indicated that the elevator was last inspected on June 16, 2011.

The records show 56 violations of the city's building code involving some of the building's 13 elevators dating back to 2001. The last citation occurred in 2009, and all of the complaints are listed as resolved by the Buildings Department.

But Sclafani said it is important to keep in mind that the number of elevator accidents are very low in relation to the number of elevators and trips made on a daily basis.

"Fatal elevator accidents are very rare when you consider we have approximately 60,000 elevators with millions of trips each day," Sclafani said. "In 2010, there were three fatal accidents in New York."

ConsumerWatch.com reports that about 27 people are killed in elevator accidents per year, according to the U.S. Bureau of Labor Statistics and the Consumer Product Safety Commission. About 10,000 people every year are injured because of elevators.