SEATTLE – One of the operations buildings for the new SR 99 tunnel suffered some damage during a testing session Thursday night, WSDOT said.



“Pressurized air forced a door open and caused some drywall damage in the north operations building,” WSDOT said in a statement.



Nobody was hurt, and there was no structural damage.



“This is precisely why the contractor has an extensive testing protocol in place,” the statement reads. “We are investigating the cause and will make adjustment to design and operations, as needed.”



WSDOT said the incident happened as Seattle Tunnel Partners tests 90 safety and operations systems in the tunnel and operations buildings.