callofs - To add even more weight to your view, "and mine by the way" Of how non effective Bioquells product really is, compared to a Nightingale UVGI which would be left running on a contiuous basis...........Ive just recieved a reply from Alistair Frost at Bioquell. My question was how long does a ward stay clean and free of bugs once treated by them and their product. His reply is as follows....How long before re-contamination? as you can imagine it is impossible to answer this as it is dependant on carriage of the patient the room /ward is reoccupied with, we have seen that because the removal of pathogens is complete that the bio-burden in a room re-occupied by heavily colonised and infected patient took two weeks before swab tests identified enviromental contamination but this is not exhaustive results.............So at best then they can keep the place clean for two weeks............Talk about a waste of time and our money!!!,,,,,,,,,