I note your suggestion that high efficiency particle air filtration should be utilised more widely within healthcare buildings.  Generally, apart from specialist areas, existing hospital buildings are not constructed to air tightness levels that would benefit from this approach.  In addition, the majority of healthcare premises, including those located in inner city areas, employ natural ventilation as part of the ventilation strategy for the building in conjunction with the necessary mechanical ventilation systems.  

'HTM 03-01: Specialised ventilation for healthcare premises' was published in November 2007 and developed just prior to the adoption of BS EN 13779:2007.  HTM 03-01 will be updated to reflect current research and standards when it is reviewed.  In light of the concerns raised in your correspondence, the Department will consider adding HTM 03-01 to the list of prioritised guidance due to be considered for review within this financial year.