CHICAGO — A month after a city panel recommended Chicago overhaul its data center regulations, Mayor Brandon Johnson has placed new rules and reviews on the industry as he calls for a pause on new data centers. New noise regulations on data centers’ cooling equipment, generators and other mechanical systems. Chicago is home to about 39 data centers, which house the computers needed for products like media streaming, artificial intelligence and cloud storage. Johnson’s administration is also pushing for a moratorium on new or expanded data centers until those updates are finalized. The working group also recommended the city create a permitting program specific to data centers and require most data centers to undergo a zoning review that needs City Council approval.