Pieces of glass fell 18 floors to the street. Firefighters who responded said about 50 or 60 pounds of glass landed on West 57th Street and its sidewalk.
"Most of it stayed in, it was just cracked, so we had to remove it and pull it into the building," Fire Chief Tom Marra said.
Firefighters said a piece of machinery bumped into the window, breaking the glass.
Those injured included a renovation worker and two pedestrians. One, a tourist from North Carolina, stumbled into a coffee shop.
"I was feeling sorry for her because the reaction on her face was like she was in pain," Anna St. Hill, a waitress, told WCBS News.
West 57th Street, one of the major thoroughfares in midtown Manhattan was closed to vehicular and foot traffic between Fifth and Sixth avenues after the accident.