The underground car park ventilation system was installed around 1977 when the car park was built. It services all car park levels using a supply and extract air plant with filters and duct work.
The system is maintained and inspected on a monthly basis. This was last done on 17 March 2008. Deep cleaning of the ducts was last completed during 2007. The system was last fully operational around 2001 when the original automatic system controls needed to be replaced with an interim manual controls arrangement. Since then a reduced level of air changes has been provided. However, the rate of air change will be increased by 21 April 2008 to the original level. Major refurbishment of the system is planned currently for 2010-11.