Bed Microenvironment in Hospital Patient Rooms with Natural or Mechanical Ventilation

We studied how to provide patients in bed with thermally comfortable microenvironment in both naturally and mechanically ventilated hospital rooms for both winter and summer seasons. A climate chamber was used to resemble a hospital room and thermal manikin to simulate a patient lying in a bed. The °manikin was dressed and covered by a quilt with its head resting on a pillow. The effect of local heating was studied at room air temperature of 10 and 16 °C and of local cooling at 28 and 35 °C. Electrical radiant heater, heated blanket, heated pillow, personalized ventilation (PV) and heated boots were used to provide local heating and PV, cooled mattress, ventilated bed and cooling fan to provide local cooling. The heating/cooling effect of the methods (when used alone or combined) was identified by comparing heat loss from manikin’s body and equivalent temperature with these obtained at a reference temperature of 22 °C. The effect of air movement (0.2, 0.4 and 1 m/s) at the bed vicinity was also studied. Electrical radiant heater in combination with heated bed showed to be the most effective at 10 and 16 °C and the combined use of PV and cooled mattress or ventilated bed was the most effective at 28 and 35 °C. Air movement with elevated velocity, especially 1 m/s, decreased the local heating/cooling effect.