West Midlands Railway Signalling Centre
Network Rail
Background
The Signalling Centre at Saltley will provide Network Rail with a centralised facility for the West Midlands using a VDU based signalling control system. The facility will accommodate 24 desk positions and migrations from existing facilities throughout the West Midlands will take place on a rolling programme with completed in 2014.
Project
CCD's role in the project was to provide specialist ergonomic support, interior design and furniture design services for the design and fit-out of the control room.
The control room is in an existing concrete structure which is a circular in plan, 32 metres in diameter, with a domed ceiling and no windows. The design challenges were the acoustic anomalies that occur within circular/domed spaces and the psychological problems associated with 24 hour working in a windowless environment.
Implementation
Plasterboard ribs have been applied to the underside of the domed ceiling to provide visual definition to the dome itself. The required acoustic performance is achieved by applying sprayed sound-absorbent plaster between these ribs. Purpose-made acoustic sails are suspended from the underside of the dome on stainless steel cables. These sails are faced top and bottom with sound-absorbent melamine foam to which transparent fabric is bonded.
Acoustic performance has been further enhanced by fitting a series of concave pilasters around the perimeter wall to break up sound reflection paths. The pilasters and the wall areas between them are faced with sound-absorbent foam with acoustically transparent fabric stretched across. Prior to commencement of the works on site, an acoustic computer model was constructed to verify that the sound reverberation time would be at an acceptable level.
A specialised, highly controllable, diffuse lighting scheme was designed to counter the ‘windowless environment' problem. The underside of the dome is washed with light from luminaires mounted on the upper side of the acoustic sails and from concealed lighting in the room perimeter bulkhead. Direct/indirect luminaires are suspended from the underside of the sails. These luminaires enable a wash of light to be "thrown" up onto the underside of the sails so that they do not appear as silhouettes against the uplit dome. Illumination levels at ceiling level and on the working plane can be separately controlled and the scheme enables levels to be adjusted to reflect external conditions to compensate for the lack of windows. On a winter's afternoon, for example, the uplighting to the dome can be gradually dimmed to reflect the fact that it is getting dark outside.
To provide a psychological visual link with the outside world, three artwork triptychs were commissioned from the artist Gudawer Kilari to mimic windows by providing distant views. These are digitally manipulated photographs of Ironbridge, Warwick Castle and the Malvern Hills - all of which are located within the West Midlands area. The images were printed onto fabric and stretched across the sound absorbent wall lining. A further psychological link with the outside world is provided by the use of natural timber for the built-in perimeter storage cupboards and the central ceiling feature. Cherry was chosen for its visual "warmth".
The workstation furniture and control room layout were developed through a proven ergonomic design process of task analysis, workload assessments, plotboard workshops and a series of full-scale mock-up trials. The trials were conducted within the actual control room area in the Saltley building to allow stakeholders and, most importantly, eventual signalling centre users to participate in the development of the most appropriate designs.
Outcomes
CCDs involvement in the this project has transformed a problematic workspace, particularly with regard to acoustics and lighting, into a comfortable and visually interesting workspace to support Network Rail signalling in the West Midlands.