Francis Crick Institute
EMI/RFI Site Testing, Utility & LV Electrical Distribution Simulations & Impact Analysis
London, United Kingdom
The Francis Crick Institute formerly known as UKCMRI, is a shared facility of combined medical and scientific research within central London. This world-class biomedical research institute hosts several EMI sensitive imaging tools, diagnostic tools and electrophysiology instruments in which Vitatech provided laboratory design analysis and shielding recommendations as the EMI/RFI consultant of record for HOK.
The electromagnetic interference (EMI) on site emanates from several different sources around and within the site, which all require specific types of shielding. Firstly, there are the various electric rail systems around the site: The overhead 25kV AC catenary within the Thameslink tunnel at the East end of the site, the overhead EuroStar 25kV AC catenary at St Pancras and, last but not least, the unique London Underground 630V DC four-rail system. Electrified rail propulsion motors move the trains by converting traction currents into kinetic energy. Depending on the electrified supply, time-varying AC or DC current, magnetic fields emanate from the overhead catenary cables and fourth rail supplies as the trains and subways move along the rails. The magnitude of the magnetic field emissions are related to the amount of current required to move the trains, which depends on the number of cars and passengers, number trains (rush hour), and proximity (distance) to the tracks. The ferromagnetic (steel) mass of the moving trains, elevators and vehicles also generate quasi-static DC magnetic fields by perturbing the Earth’s magnetic field. The Francis Crick EMI sensitive research instruments (i.e., TEMs, SEMs, NMRs, MRIs, etc.) are impacted by the St. Pancras trains, underground tube beneath the British Library and the moving lorries and double-decker buses moving on the nearby streets. Another problematic EMI magnetic field sources are generated by the time-varying 50 Hz underground electrical power distribution feeders located around the perimeter of the Francis Crick site and from localized building sources (i.e., substation, cable trays, UPS units, adjacent equipment, etc.) within the building. Also, moving elevators, dumb waiters, and metal carts within the building generate quasi-static DC magnetic emissions by disturbing the Earth’s magnetic field.
This new facility will accommodate 1,400 scientists and 120 research groups. It is a partnership between six organisations: Cancer Research UK, the Medical Research Council, the Wellcome Trust, UCL (University College London), Imperial College London, and King’s College London.