The exposure of a doctor and a patient to air coughed by a second infected patient was studied in a mock-up of two-bed hospital infectious ward with mixing ventilation at 22oC (71.6 F) room air temperature. The effect of posture of the coughing patient lying sideways or on back), position of the doctor (either facing the coughing patient or standing sideways) at three ventilation rates (3 h-1, 6 h-1 and 12 h-1) was examined. Thermal manikin with realistic body shape and surface temperature distribution was used to resemble the doctor. The coughing patient was simulated by a heated dummy with a cough generator. Another heated dummy was used to simulate the second patient in the second bed. The cough consisted of 100% CO2. The Peak Cough Time was 4 s, when the doctor was close to coughing patient and increased more than twice for the exposed patient. The level of exposure (Peak Concentration Level) depends on the positioning relative to the cough direction: lying or standing still, facing or turned sideways and changed varied 194 to 10228 ppm. Ventilation rates of 12 h-1 (recommended by present hospital standards) resulted in increased background exposure levels and may suggest risk from airborne cross-infection.
|Title of host publication||Proceedings of ASHRAE IAQ 2010|
|Number of pages||16|
|Publication status||Published - 2010|
|Event||ASHRAE IAQ 2010: Airborne Infection Control - Ventilation, IAQ, & Energy - Kuala Lumpur, Malaysia|
Duration: 10 Nov 2010 → 12 Nov 2010
|Conference||ASHRAE IAQ 2010|
|Period||10/11/2010 → 12/11/2010|