Fläkt Woods launches new generation of ventilation systems for cleanrooms

Fläkt Woods Group has been supplying air-handling units for hospitals for several decades. The air handling unit and the air distribution terminal devices are important parts of the ventilation system and now Fläkt Woods is introducing further developments in room air distribution for demanding cleanroom environments. Elea CARE is an air distribution system from Fläkt Woods that not only takes advantage of the displacement ventilation method, but is also equipped with newly developed low resistance HEPA filters and a room air recirculation system. Both the supply and the recirculated air pass through the filters so that the supply air is clean and particles produced in the room, either from the people in it or from a process, are filtered out. Elea units can replace the existing displacement terminal units without further alteration to the existing ducting and air handling system, the company says. With conventional methods, HEPA filters and diffusers have only partly satisfied the need to control particle concentration in rooms. Such systems seek to ensure that the air entering the room is clean, with the aim of diluting the concentration of particles in the room. The problem is that people, tools, machines, etc, generate the majority of particles in the occupancy zone itself, and mixing systems tend to spread that pollution all over the room and even transmit it to other spaces in the building. Cleanrooms with HEPA filter ceilings can solve the problem since they provide a laminar flow of air vertically down through the room, and all contamination created within the room is carried away in the exhaust air. Displacement systems use the heat sources in the room to create a temperature gradient and a slow movement of air from the floor mounted displacement terminal towards the ceiling. Particles are carried by the upward currents of air from the heat sources, and the dirty air is extracted at ceiling level. If the air supplied to the displacement terminal has been through a HEPA filter, then a relatively clean zone is created near the terminal itself. Increasing the grade of filtration in the air handling system does not significantly improve the air quality in rooms with a high particle load. Elea CARE addresses this problem by adding air recirculation with HEPA filtration within the room. Fresh air is passed through a HEPA filter before being supplied to the room using normal displacement techniques, while a small fan recirculates room air through a second HEPA filter. Both the supply and the re-circulation filters are grade H12, which means that 99.95% of all particles will be taken out of the air. The device also features an integrated exhaust air section with a third HEPA filter to clean the air before removing it from the room. The pressure drop is low and the device is designed to replace existing displacement terminals without any need to increase the supply airflow. Elea CARE is available in five sizes for airflows up to 540 m3/h. With this system a conventional ventilation system can be used to achieve clean air zones without the need to build expensive clean rooms. Enquiry card number: 129