SAN FRANCISCO (KGO) -- As more than 150 people remain unaccounted for in the deadly Florida building collapse, a UC Berkeley professor is weighing in on how something like this happened and whether a similar collapse could happen in San Francisco.
Khalid Mosalam is a professor of structural engineering. He joined ABC7's program "Getting Answers" on Monday to discuss the building collapse that has now claimed 11 lives.
"It will take a while until we know exactly what happened," Professor Mosalam said. "But considering this building was constructed 40 years ago, one can only speculate that the code provisions that were followed at that time were not as robust as what we have these days."
In order for a collapse of this magnitude to occur, Mosalam said there had to have been an abnormality in the building, something related to the foundation or soil.
He said Florida's marine climate and erosion related to the building situated along the waterfront could have also compromised the building's capacity.
"Fortunately these failures are very rare," he said.
However, the rarity doesn't lessen the consequence, he said.
Now could this happen in San Francisco, a city filled with tall buildings, surrounded by water?
"Here in California we worry a lot about earthquakes obviously, so most of our structures are designed with that in mind," he said.
And with that, he said, comes resiliency.
San Francisco's Millennium Tower is known to be sinking, but Mosalam believes it's not a big concern.
He also mentioned the distinction between a skyscraper and midrise building
As of February 2020, the 58-story building had sunk 17 inches and tilted two inches since it first opened in 2009.
The UC Berkeley professor emphasized a plan needs to be put in place because of "external" factors -- like a fire or earthquake -- that can lead to abnormal conditions.
"If we have a situation of a building sinking, it has to be monitored. There's no way around it. If we know there are these abnormal conditions, we have to put a monitoring system in place so we have ample warning before a catastrophic failure like this happens," he said.
The condo building in Florida was built four decades ago with an older design and faced compromised capacity due to the harsh climate, which can lead to erosion and micro-cracks of concrete, he said.
"Fortunately that's not the situation we have in San Francisco," Mosalam said.