ACR Journal

December 2020 | January 2021 AIR MANAGEMENT 14 Tips for e ective laboratory air management Volume 7 No.1 Effective air management is key to the operation of today’s laboratories. Advanced control of air supply and extraction can make it possible for laboratory spaces to be used more productively, whilst reducing overheads and safeguarding the health, safety and comfort of all building occupants. But how can air management systems be designed to deliver on all these priorities? Here, Ian Thomas, Product Manager – LabControls at TROX UK, considers four important criteria: health and safety, energy eciency, flexibility, and comfort of occupants, and suggest tips for achieving the site’s objectives, with examples of best practice from recent projects. Safeguarding health and safety The design of an air management scheme for a laboratory facility will, of course, be dictated by the containment levels required in various zones of the site. This, in turn, determines the optimum supply and extraction strategy and identifies the appropriate filtration requirements. The new Quadram Institute building, based at the Norwich Research Park, for example, needed a scheme which would enable multiple clinical and research operations to be accommodated within a single new build development. The site includes Containment Level 2 and 3 Laboratories, as well as being a major Clinical Trials facility and a centre of excellence for endoscopy. To meet the specific containment requirements in dierent zones, the TROX EASYLAB room air management system installed at the site controls a pressure cascade. Laboratories are controlled at larger negative pressures than the adjacent circulation spaces serving them, to ensure there can be no reversal of airflow under normal operational conditions. The suite also has an automated ventilation sequence that allows ventilation shut down, fumigation and purge of labs in a number of combinations to allow maximum flexibility. This automated ventilation sequence works by switching the TROX EASYLAB between dierent flow rate set points and pressure set points to achieve the desired ventilation strategy. Technical specialists worked with TROX during the design phase to determine the most appropriate HEPA filter cells and diusers for the scheme. This resulted in the installation of specific room pressure control capabilities for the Containment Level 3 labs, and volume oset tracking controls for the Containment Level 2 spaces. Energy efficiency The energy consumption of laboratories is often more than three or four times that of oces on a square metre basis. 1 This can mean that laboratory buildings are responsible for between 50% and 80% of the total energy-related (non-residential) carbon emissions of research-intensive universities. Government research facilities, hospitals and private sector laboratories are similarly aected, with energy consumption presenting significant financial and environmental challenges. The higher energy costs and carbon emissions of laboratories are typically associated with the air supply and extraction requirements of fume cupboards. When sashes of fume cupboards are open, the volumes of air required to maintain a safe working environment for laboratory personnel increase significantly. For example, a 900mm wide cupboard with a maximum sash height of 500mm and face velocity of 0.5 m/s would extract approximately 225 l/s of conditioned air from the room. So managing the supply and extraction of conditioned air eectively is key to reducing energy consumption, and variable air volume capability is crucial. Based on the example above, the minimum air volume for a variable air volume fume cupboard would only be around 55 l/s when the sash is closed, saving 170 l/s of conditioned air, whenever the sash is in the down position. Best practice is to install a room air management system to fully integrate fume cupboard air supply and extraction with the wider air management systems to prevent wastage. The TROX EASYLAB system, for example, makes it possible for all input and extract air for the laboratory to be controlled automatically to ensure that the required ventilation strategy and levels of safety are maintained. With this TheUniversity of Birmingham’s newCollaborative Teaching Laboratory (CTL) The TROX air management system helps to optimise the energy efficiency of fume cupboards Trox air management.indd 14 03/12/2020 11:51