CASE STUDY | NHS NIGHTINGALE HOSPITAL LONDON Ventilation l Use existing systems and modify controls to maximise fan duty and ensure full fresh air with no recirculation l Introduce a pressure regime to push air from clean areas to dirty areas and out of the building Ensure volume is appropriately sealed and openings filled accordingly Managing clean/dirty air 1 Protected lobby 2 Nurse base 3 Bed bay 4 Automated fan 5 High level ventilation on full fresh air to the external wall. The bedheads in one row back onto the bedheads in the adjacent row, and between them is a 1m-wide service corridor positioned above a row of existing floor boxes. To build the bedheads, ExCeL put BDP in touch with GES, its exhibition stand builder, which uses a component-based system to construct stands. GES demonstrated the systems capability by producing a series of six bays and bedheads. The layout worked brilliantly, dictated by the floor box spacing and exhibition kit, says Hepburn. Meanwhile, the RSPs Gerry Connor worked with ExCeL to establish how the electrical installation could be quickly repurposed. The north and south halls are Wall-fans and a pressure relief damper ensures air always moves from the clean corridor to the wards each served by five service spines fed by a transformer supplying two 800A and one 400A busbars. The busbars run north-south beneath the hall floor linking the floor boxes via trenches running east to west. During an exhibition, a tap-off box from the respective busbar enables power to be delivered to the stands using modular wiring terminated with commando sockets; the wiring connects through the floor boxes to a fused switch and then to a floor-mounted distribution board fitted with commandosocket outlets. Connor decided to use the same system. He located the fused switches and distribution boards in the service corridor between bedheads. Sections of bedhead trunking were assembled on site by the electrical contractor using standard antibacterial dado trunking fitted with outlets for the medical gases and eight double-electrical sockets, nurse-call and a light switch for the bed light. To enhance resilience, the bedhead was configured so that four of the electrical sockets are fed from one circuit, four from another. We reused all of the exhibition kit for speed and flexibility, Connor says. The bedheads were estimated to have a 7A load, which will be a significant electrical demand if all 4,000 beds are in use. But, because it was unclear what equipment was to be connected to bedheads it was decided that significant additional electrical loads come with their own power supply, such as mortuary fridges and CT scanners. Connor also had to enhance the electrical systems resilience. There was an existing lifesafety system at ExCeL, but only supplying escape lighting and security. Fortunately, there were two high voltage (HV) supplies. Switching from one to the other takes time because the HV ring needed to be deenergised and then re-energised, so additional resilience had to be added. We had to put in a 600kW battery UPS and a 1600kVA generator to support what we called the essential busbar on each of the risers, says Connor. In total, 7.2MW of UPS and 19.2MW of generator provision will be 16 May 2020 www.cibsejournal.com CIBSE May 2020 pp14-17 NHS Nightingale.indd 16 24/04/2020 16:29