INTERVENTION STUDIES (AIR FILTER, HEPA VACUUMING & STEAM CLEANING) IN NON-COMPLAINT, RESIDENTIAL HOMES IN PERTH, WESTERN AUSTRALIA C. D. Cheong 1,2 , H. G. Neumeister-Kemp 2 and P.C. Kemp 2 1 School of Environmental Science, Murdoch University, South Street, Perth, WA, 6150, Australia 2 Mycologia Pty Ltd, Unit 1, 454 Scarborough Beach Rd, Osborne Park, WA 6017, Australia Abstract Three housing intervention studies were conducted in non-complaint residential homes in Perth, Western Australia. The use of portable air filters, HEPA vacuuming of carpets and soft furnishings and steam cleaning of carpets were conducted. Results showed that all three interventions had an affect on fungal and particulate levels. The principle conclusion is that unless the primary source of fungal inoculum in the house (carpet and soft furnishings) is addressed, the outdoor air remains the main source of fungi and particulates in the home indoor environment. Keywords HEPA vacuuming, air filter, steam cleaning, carpets, housing interventions, fungi, particulates 1. Introduction In January 2009, the National Centre for Healthy Housing (NCHH), in conjunction with the Centre for Disease Control and Prevention (CDC) and the National Centre for Environmental Health/Agency for Toxic Substances and Disease Registry, released a comprehensive summary report (‘Housing Interventions and Health: A Review of the Evidence’), on Healthy Housing Intervention Research (NCHH, 2009). The aim of the review was to close the gap in understanding of the numerous housing intervention studies being conducted worldwide and their impact on health status. Among the conclusion reached by the panel reviewing current research evidence on Interior Biological Agents (Toxins), was that there was more need for field evaluation of air cleaners, steam cleaning and vacuuming. Titled ‘Promising Interventions that need more Field Evaluation’, the scientific review panel concluded that more evidence was required and that the interventions yielded promising but not conclusive results. Further delineation of approaches and better definitions of interventions was highlighted as ways to reduce the gap in knowledge. This research paper highlights three such intervention studies conducted in non- complaint, residential houses in Perth, Western Australia. The three interventions included the use of a portable HEPA filtration unit, HEPA vacuuming of carpets and soft furnishings and steam cleaning of carpets. 2. Methods Fifty five residential dwellings within a 15km distance from Murdoch University, Perth, Western Australia were selected. All homes were single storey, of brick construction over a concrete pad with their age ranging from two to more than 30 years. Selection criteria required that all homes be fully carpeted (tufted wool or synthetic), naturally ventilated, non smoking and non complaint (no mould or indoor air quality problems). In five homes a portable HEPA air filtration unit (Defender TM , Captiva filtration, HMI Industries) was operated in the bedroom of the participant. The portable air filtration unit uses a fan to