Connect 2 Cleanrooms (C2C) was appointed to deliver a 325m² cleanroom within the building. The cleanroom features two zones—one change area and one satellite engineering zone with an open plan layout featuring a high bay and a low bay.
Work commenced on site in July 2021 and full ‘as built’ validation was completed in October 2021.
Each filter fan unit went under filter integrity testing to verify performance and air particulate counts were taken. The validation confirmed that the cleanroom operates well within the limits of its ISO 14644 Class 6 requirement. At 0.3 micron the air particulate count results ‘as built’ were 5,962, well under the ISO 6 maximum concentration limit of 102,000.
Process-built layout including horizontal air flow
To accommodate the movement of large equipment and materials within the satellite engineering zone, the cleanroom incorporates a substantial gantry crane. To enable effective product flow within the space the cleanroom features a split height ceiling with a 6 metres internal height along the high bay. A small telescope could be turned from a horizontal to vertical position, or a small spacecraft could be worked on in the high bay, whilst the low bay hosts a bench with optics.
Due to this considerable ceiling height, an innovative HVAC approach was required to achieve the required ISO 14644 class 6 classification. Volumetric supply modelling showed that a vertical downflow of air would not have achieved ISO class 6 at a working plane due to dilution of airflow from the 6m height—even with terminal HEPA filtration from C2C’s contemporary decentralised air handling system.
Efficient air handling design
To achieve the required particle concentration limits, C2C designed a system using horizontal laminar flow with room side replaceable HEPA filtration for maintenance access within the controlled zones. This gave the required air velocity and reduced the risk of airflow disturbance at operating heights.
The facility is optimised for high standards of air quality and energy efficiency. The UltraTech Versatile insulated panel system creates an airtight seal in the finished envelope, controlling leakage rates from the room and meeting the required acoustic criteria. An airtight envelope and high levels of recirculation in the HVAC system allow the facility to operate effectively with a performance-based air change rate.
An energy-efficient design and innovative approach to air handling reduce the volume of processed air required to meet the cleanliness standard. The energy efficient design reduces the initial build outlay and ongoing maintenance costs as the overall number of fan filter units required is reduced.
Due to the sensitive nature of materials used in the satellite engineering zone, humidity control is provided to achieve 40-60±10% RH, with temperature control designed to achieve 22±2˚C in all areas. To protect the integrity of each zone as the staff moves through the facility, the integrated doors feature an interlocking system.