Suwat Damnin. An investigation of concentration and identification of bacterial and fungal aerosols in indoor air environments in Siriraj Hospital. Master's Degree(Industrial Hygiene and Safety). Mahidol University. : Mahidol University, 2009.
An investigation of concentration and identification of bacterial and fungal aerosols in indoor air environments in Siriraj Hospital
Abstract:
The indoor air quality of hospitals needs to be monitored and affects healthcare
quality. The purpose of this study was to determine microbiological indoor air quality of the
Out Patient Department (OPD) building at Siriraj Hospital by using a single stage bioaerosol
impaction sampler. A total of 224 air samples and other environmental data were collected
and analyzed from 14 sampling sites in April-June, 2008. The results revealed the medians of
fungal concentration ranged from 1.5 x 102 to 7.6 x 102 CFU/M3 with a predominance of nonsporulate
septate mold, dematiaceous mold, Penicillium, and Aspergillus spp. All sampling
areas (except the dispensary) had fungal counts within the acceptable level of 500 CFU/M3
(Guideline for good indoor air quality in office premises, Ministry of the Environment,
Singapore). In contrast, all sampling areas showed high bacterial concentrations (>500
CFU/M3) with medians ranging from 9.6 x 102 to 2.7 x 103 CFU/M3. The majority of the
bacteria were representative of normal skin flora, e.g., coagulase-negative staphylococci,
Bacillus spp. Factors affecting bacterial and fungal concentrations were temperature, relative
humidity, occupant density, and type of ventilation system. The high bacterial counts in the
indoor air of OPD needs remedial action in both short and long term plans.