Additional jet fans in the tunnel

In December 2006, an additional 12 ceiling jet fans (making a total of 128) were installed to assist the operation of the in-tunnel ventilation system. The additional fans provide greater flexibility in directing air and a faster response to tunnel incidents.

This means that less carbon monoxide is building up during tunnel incidents or quick changes to traffic patterns. The frequency and duration of tunnel closures since 2006 has been reduced.

Fast facts

• Tunnel jet fans typically discharge air at 90-110km per hour.
• The purpose of the jet fans is to push the air inside the tunnel to keep it moving.
• The jet fans are as powerful as a family car.
• The physical size of a tunnel jet fan is similar to that of a commercial airliner, however, they are only about 1% as powerful.
• Tunnel jet fans are extensively silenced to ensure safe noise levels for motorists inside the tunnel.