Cones and caution signs were immediately placed on the sidewalk below the unit.
TIMELINE: Issues with San Francisco's tilting, sinking Millennium Tower
On Friday, large scaffolding was ordered by the Department of Building Inspections after two engineers examined the cracked window pane Thursday.
"Then it wouldn't hit anyone, it would hit the scaffolding, so anyone walking under that would be better protected," said Bill Strawn of the San Francisco Department of Building Inspections.
It's unlikely any pieces would fall from the unit on the 36th floor because the crack is contained within a silicone sealant.
Tom Miller is the attorney for the homeowners association. He revealed some new information regarding the replacement of the window.
RELATED: San Francisco's Millennium Tower is leaning, sinking and now cracking
"We were just informed that the window product is now discontinued so we have to go back and find a like-kind in quality, hurricane resistant and seismic resistant," Miller told ABC7 news.
The manufacturer is "Enclos Corporation" based in Minnesota. We contacted the company but they would not confirm the information.
The building opened in 2009 and has sunk 18 inches and has tilted to one side.
Engineers hired by the homeowners association believe the fracture is not structurally related and are now asking for a full inspection of all the windows.
RELATED: $5.6M Millennium Tower condo for sale in SF: Its visual and financial vertigo
"We want to see whether that same installation problem with the window is systematic, meaning it may be the same problem with the other window in the building," demanded Miller.
The Miller Law Firm, on behalf of the Millennium Tower Association, tells the building inspector that they've performed preliminary inspections of the cracked glass and have secured options for exterior observations. They say they will use drone photography and high-powered telephoto lens photography from adjacent buildings on Saturday. They'll also hire someone to rappel down the building next week to photograph the curtain wall and glass and tape up the glass from the exterior to make sure it's safe.
To see the full report from Millennium Tower management, visit this page.
RELATED: Costly fix found for sinking Millennium Tower in San Francisco
Find more stories and videos on the Millennium Tower on this page.