Air quality “appears to have been virtually ignored” in the British Standards Institute’s (BSI) new Publicly Available Specification, (PAS) 5748, which “provides a framework for the planning, application, and measurement of cleanliness in hospitals”, a leading UK ventilation duct cleaning specialist claims.
Ian Wall, sales director at Halesowenbased Ductbusters (HEJ – September 2010), explained: “Cosmetic cleaning of ventilation grilles’ exterior (as advocated in PAS 5748) may leave a clean-looking surface, but fails to address the very serious, and in some cases fatal, consequences of contaminated air ducts. “All initiatives to improve and measure hospital hygiene are welcome. However it is of major concern that such a lengthy, detailed document barely touches on duct cleaning. Any medical facility can have the most sparkling floors, surfaces, and equipment, but if the ventilation ducts are dirty, infection will spread.” Ian Wall explained that highly infectious diseases like MRSA and Clostridium difficile were not only carried through ventilation systems, but could also thrive and feed on flakes of dead, dry human skin – “a large component of hospital dust” – and build up in ventilation ducts. He added: “However diligently healthcare teams clean surfaces and equipment, if ducts are not regularly cleaned, the impact of their efforts on controlling infection will be considerably diminished.” Ductbusters emphasises that sound guidance on regular duct cleaning is provided in the Department of Health’s HTM 03-01 Healthcare Technical Memorandum, and in the Heating and Ventilating Contractors’ Association’s TR19 standard, 2nd edition, which recommends that surface dust levels within ductwork should not exceed 60 microns for supply, and 180 microns for recirculation and extract. Should levels exceed these, the standard says cleaning should be undertaken. Another duct cleaning advocate, Dr Ghasson Shabha, facilities management MSc course leader at the School of Property, Construction and Planning at Birmingham City University, said: “MRSA has increasingly become a major source of healthcare-associated infection in British hospitals, and a main contributory factor to 100,000 cases annually. It thrives in relatively nonhumid environments, feeding on dead, dry human skin. It withstands desiccation at temperatures of 18-37°C, and is thus a frequent component of hospital dust, making it more likely to spread via ventilation and air conditioning. Hospital ducts, depending on room type and function, should be cleaned every three to six months, and filters, depending on whether multi-or single-layered, ideally replaced six monthly.”
