NEW YORK (CBSNewYork) -- Sparks were flying at the scene of the deadly crane collapse on worth street in Tribeca as crews used blow torches to carefully dismantle the 565-foot boom and find out exactly what caused it to come down.
"It goes from A-Z. We're gonna be talking about looking into possible metal fatigue, make sure the pins that are connecting pieces together, the counterweights, any wind information that's possible," Buildings Dept. Commissioner Rick Chandler told reporters.
The crane is so huge it has to be cut into 35 pieces and hauled away and the fatal accident may lead to changes at construction sites citywide, as reported by CBS2's Brian Conybeare.
Construction workers in a nearby building captured the crane's collapse onto Worth Street around 8:30 a.m. Friday. The crane was just installed at 60 Hudson Street last Saturday, CBS2's Ilana Gold reported.
Photos from inside the nearby New York Law School show a 2 ton hook and weight ball that crashed through the building's ceiling, leaving a gaping hole and broken windows in its wake.
Officials said on Saturday that despite damage, all buildings in the area have been deemed secure. However, all partial evacuation orders are still in effect, officials said.
Tons of metal slammed onto the street with little warning. The crane crushed more than a dozen cars on Worth Street and trapped one driver.
"It made a loud noise and we all ran to help. We saw a man trapped but they wouldn't let us go no further," said witness Teddy Johnson.
"You heard the boom and then you run to the windows and you see a crane falling on the street," said one witness.
David Wichs, 38, was killed instantly as he walked along Worth Street. Three others were injured, including 73-year-old Thomas O'Brian, who suffered a head injury.
"A lot of people are very lucky that they didn't lose their lives," said one man.
The collapse happened as the crew was lowering the crane due to high winds. A veteran operator was inside the control cab when it flipped upside down.
The operator identified as Kevin Reilly of Port Jefferson, Long Island has been questioned about how he lost control of the crane.
CBS2 obtained a photo of the wind meter inside the crane's cab. It shows a steady wind at 18 miles per hour as the process to lower the crane began.
"The wind started blowing so they went back up with it. On the second attempt to lower it, that's when it got out of control and then it collapsed," said witness Dan Vaughn.
The crane was installed to replace generators and air conditioners on the building's roof. Just 24 hours before, inspectors for the city's Department of Buildings gave the crane, manufactured by Bay Crane, the all clear.
"It was approved and it submitted by an engineer and went over with my staff," said Chandler.
After inspecting the damage at the crash site, Mayor Bill de Blasio ordered all 376 crawler cranes and 53 tower cranes operating in the city to be secured.
"I'm not going to minimize what happened. We have to figure out what happened and we have to make sure it doesn't happen again," the mayor said.
After ordering work to stop at all crane sites in the city on Friday, officials said tower cranes were allowed to return to work Saturday. All crawler cranes must be inspected before they can recommence work. Officials said inspectors were deployed throughout the city to get it done.
There have been at least four significant crane collapses in the city in the past 2 1/2 years, according to city Comptroller Scott Stringer. Yet, life-threatening conditions still exist.
Stringer told WCBS 880's Sophia Hall there was a study completed in 2008 with recommendations on how to do better.
"The Department of Buildings implemented only eight of the 65 recommendations put forth by the $5.8 million study -- well, that's not good enough," Stringer said.
The comptroller said he thinks cranes should be equipped with black boxes, like trains and airplanes.
"So that we can have a better understanding of how these accidents are investigated," he said. "They don't want to have anything to do with that as well."
The Department of Buildings said it implemented many of the recommendations and there is more oversight of cranes than ever before.
Meanwhile, officials said it could take days before the crane is removed from Worth Street and streets in the area will remain shut down until that happens.
Flatbed trucks were brought in by Bay Crane to help remove the structure. The crane will have to be taken apart and removed in sections.
Chandler said crews are cutting the crane in a way that will not compromise forensic evidence as the investigation into the cause of the collapse moves forward.
"The main point is to cut them in locations that doesn't compromise the forensic engineering value, so that we can have experts study how these pieces failed," Chandler said.
Office of Emergency Management Commissioner Joseph Esposito said they hope to have the crane fully removed from the street by Sunday night.
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