An evaluation tool of infection risk analysis for drainage systems in high-rise residential buildings

This study proposes a simple risk analysis tool and evaluation level for the probable infection due to a contaminated drainage stack in residential high-rise buildings in some Asian cities which have equivalent drainage systems. The methodology would follow the conception of FMEA (Failure Mode Effects Analysis). In particular, key risk factors including connections between appliance and stack, the plumbing system, ventilation, equipment life and maintenance were surveyed and used to evaluate the overall risk associated in high-rise residential buildings with Monte Carlo simulations. With the proposed tool, regional risks of infection due to the building drainage systems were estimated, with respect to the city building age and height profiles. The results showed that a city with a high-rise environment would associate a higher spreading risk due to the drainage system. Practical applications: Following the outbreak of SARS (Severe Acute Respiratory Syndrome) in early 2003, the operational performance of drainage systems in high-rise residential buildings has become a major concern. The assessment system would be practical and sensible for evaluating the infection risk in building drainage systems for both existing buildings and new construction. The assessment tool may provide the government, designers and the occupants a source of reference to judge drainage system performance in either new construction or the existing building, so that improvements would be conducted.