Building up its range of carbon air filters for ductless fume hoods and recirculatory filtration enclosure systems Carbon Filters Direct is building up its range of carbon air filters for ductless fume hoods and recirculatory filtration enclosure systems. Carbon Filters Direct, a UK based manufacturer of replacement carbon air filters for ductless fume cabinets and recirculatory filtration safety enclosure systems, has announced that it is extending its fume hood filter range that it will offer in the future. If you cannot find the replacement carbon filter or HEPA filter you need for your ductless fume hood on their website at www.carbonfiltersdirect.com then please call Carbon Filters Direct with details of your filter, its dimensions, the name of the manufacturer of the system and as much detail as you can offer. Carbon Filters Direct will advise you of their price to manufacture a replacement carbon filter for you, the delivery time and the price. Carbon Filters Direct is a manufacturer of generic filters which can be installed into a range of manufacturers ductless fume hood designs and enclosure systems. These include replacement filters for Erlab (Captair), Astecaire (Monair, Sensair), Bigneat (Chemcap) and Safelab, these being the ‘top four’ filters purchased in recent years. A typical filter system A filter system in a fume hood can consist of up to three filters, firstly a pre-filter, secondly a particulate filter and lastly the activated carbon (charcoal) filter. A pre-filter is a simple filter sheet, removing larger particles of around 3µm particle size and is used generally to protect the next two filters. Secondly a particulate filter may be installed. Two types of filters can be used, HEPA and electrostatic. HEPA is effective at removing particles of greater than 0.3µm at an efficiency of 99.997% and performance increases with age. HEPA filter performance is well documented and only varies because of the installation method and how even the flow is through the filter. Electrostatic filters use different materials and the electrostatic attraction built into the filters ensures good retention when manufactured; however this performance decreases with age. Documentary evidence of performance is less easy to obtain and thus in recent years a preference for HEPA has been seen. Finally the carbon filter removes chemicals. The performance of this filter is critical and this is related to the origin of the carbon, impregnants used and various other factors. The best filters on the market can remove molecules of molecular weight greater than 30 with efficiency in excess of 99.9%. More on Impregnants A fume hood filter is manufactured from an activated carbon filter media which is impregnated with added additives to optimise the carbon to make it effective for the specific uses of the laboratory fume cabinet. In years gone by the additives used were however chosen with no consideration for the environment when subsequently disposed in landfill. A CFD carbon filter only uses environmentally friendly additives. Tests have shown that activated carbon filters have an equivalent retention capacity to that of the major manufacturers and branded filters available on the market, but are available at a fraction of the cost. Replacement filters for Erlab and Captair filters in France? Please review French language website at www.filtresacharbondirect.com. For more details please contact: CARBON FILTERS DIRECT LTD Barnett House 53 Fountain Street Manchester M2 2AN, UK T: +44 (0)161 247 8350 F: +44 (0)161 247 8351 Website: http://www.carbonfiltersdirect.com Carbon Filters Direct manufactures compatible filters for Recirculatory Filtration Systems from Astecair, Bigneat (Chemcap), Cruma, Erlab (Captair), Gelair, Labcaire, Misonix and Safelab. All brand names are the exclusive ownership of the manufacturers and are used for reference only.