Measurements of air flow and microorganism concentration have been made in the stair shafts of a hospital, using a diving bell-type of pressure-recording instrument, and a sampler for the microorganisms, respectively. Results of experiments were used to calculate the flow rate of microorganisms between the floors of the hospital. A mathematical model based on simplified transport equations is proposed, which would allow the prediction of the flow field and the distribution of microorganisms in the stair shaft.
Identifies sources of gaseous, vaporous, particulate (inert and viable) and radioactive contaminants within nine functional categories of a hospital. Preliminary criteria for control purposes are recommended, and available methods of control are reviewed. It is concluded that control of gases, vapours and radionuclides may be as important to occupant well-being as control of viable particulates, and that air distribution patterns within and between rooms are as important to dilution and removal control as the quantity of air supplied to the rooms.