Seeing red

Serving Merseyside, Wirral, Chester and North Wales, the new National Blood Service (NBS) centre in Liverpool holds over 5% of all the blood collected by the NBS in the UK, supplying products and services to 21 hospitals.

The facility includes a number of cleanroom areas, where lighting has to ensure high visibility as well as maintain the integrity of the cleanrooms, even during maintenance. At the same time, the NBS wanted to ensure ease of installation, high energy efficiency and ease of maintenance to minimise cost of ownership. Working closely with the design consultants and installation contractors, Whitecroft Lighting supplied a range of fittings from its cleanroom range to meet these needs.

Blood products The Liverpool centre provides 73,000 sq ft of space, encompassing areas for laboratory services such as serology and testing, as well as the processing, supply and issue of blood products and tissues. These areas are supported by a range of administrative, storage and transportation areas. The main process rooms have an EU GMP Classification A & B requirement, with a need for luminaires for installation into non-modular or cut aperture solid ceilings. In all cases, the luminaires were required to maintain ingress protection of IP65 from front and back, even when the front frame is removed for maintenance. This has been achieved using Whitecroft's Curie luminaires, which feature smooth powder-coated, extruded aluminium frames with easy-to-clean capped screws – ensuring there are no bug traps or crevices. The use of aluminium frames was important in the specification of these fittings, because aluminium does not shed the same volume of particles as steel when the paint protection on the frame is damaged. For installation, the use of side-mounted aluminium positive jacking brackets provides ease of fitting and ensures full compression of the protective gasket seal between the body of the luminaire and the ceiling. This arrangement ensures that, in the event of ceiling compression (as can happen) the brackets can be quickly and easily adjusted during routine maintenance to maintain room integrity. An extruded triple flipper gasket seal is fitted to the luminaire diffuser frame. This gasket is very forgiving and can ensure that any small deviances in the ceiling do not cause the loss of the required IP rating. The choice of material used for the seal was also an important one. Some systems are reliant on a mastic seal around the edge of the luminaire bodies and frames. This creates two issues: first, the luminaire can be difficult to remove during maintenance and replacing the mastic seal is time-consuming, thus increasing maintenance time and downtime; second, there is a danger of contamination from fragments of dried mastic entering the cleanroom space during maintenance.

Rubber seal A rubber gasket of closed cell construction avoids these problems, and of the various types of rubber gasket available, the thermoplastic rubber used on the luminaire offers the highest level of integrity and durability, leading to a long, trouble-free life. Equally important are the materials used for the diffusers. In these luminaires, PETG (glycol-modified terephthalate) was used: it is less brittle and less susceptible to premature ageing than other plastics, and is more resistant to cleaning chemicals, thus providing a longer life. In less exacting areas such as corridors, change areas and access areas, the EU GMP C & D classification required luminaires with IP65 protection from the front and IP54 to the back when the front frame was removed. Here, Whitecroft's DTFN luminaires were installed, again with models for both modular and non-modular ceilings. As with all of the cleanroom range of luminaires, smooth powdercoated extruded aluminium frames and clean capped screws ensure ease of cleaning with no bug traps or crevices. Included in the Whitecroft portfolio is the Hygiene range of luminaires, designed for non-cleanroom areas that still demand high standards of performance and ease of cleaning. These fittings provide an IP54 barrier between the room and the void during operation, with IP20 protection when the front frame is removed. For all of these luminaires, the preferred light source was T8 linear fluorescent lamps. Whitecroft's cleanroom lighting range is also available using the latest T5 lamp technology, which offers high energy efficiency and long life, so that electricity costs are minimised and maintenance cycles are extended.