Keeping the air fresh: Testing the tunnel’s ventilation systems
Seattle Tunnel Partners is making good progress testing the operational and safety systems inside the new State Route 99 tunnel. Tests of the ventilation systems are now underway, including the giant fans connected to the tunnel’s distinctive yellow ventilation stacks at both ends of the tunnel. This video shows the ventilation tests in progress:
The ventilation system is just one of the many systems inside the SR 99 tunnel undergoing testing to make sure the tunnel functions as designed. This video shows how the safety systems work together to keep travelers safe.
Testing to make sure the tunnel’s safety systems work together, a step known as integrated systems testing, is still to come. Additional work is also taking place outside the tunnel to prepare for moving Alaskan Way out from under the viaduct and to get ready for the three-week #realign99 closure of SR 99 needed to open the tunnel.