Spatio-Temporal variation indoor-outdoor relationship of particulate matter and associated health risk
Student name: Ms Isha Khanna and Ms Krishna Malakar
Guide: Dr Suresh Jain
Year of completion: 2012
Host Organisation: TERI University
Abstract: This study aims at analyzing the variation in concentration of particulate matter (PM) across four types of sites in
Delhi city in both indoor and outdoor environments. Monitoring was done in Janakpuri, which is a residential area,
Ram Manohar Lohia Hospital and Delhi Public School, which are sensitive areas and TERI University, which is an
institutional area. The PM mass concentrations were measured at all outdoor locations, whereas both mass and
number concentration of PM was measured at all indoor locations. These concentrations were observed for six
different ranges of PM. The indoor PM concentrations varied among the different locations but outdoor PM
concentrations were almost the same except for the finest ranges.
Statistical modeling was done using regression analysis among indoor, outdoor PM concentrations and
meteorological parameters namely, wind speed, wind direction, ambient temperature and relative humidity to study
the effect of outdoor PM concentration and meteorology on indoor PM concentrations. This was done for two floors
of TERI University, ground and fourth. Most of the R2
values were greater than 0.90 indicating a very strong
association between the indoor-outdoor PM concentrations. This association was particularly strong for the fourth
floor. Temperature was found to impact indoor concentration of almost all the finer ranges of PM (less than 3 µm).
The coarser particles, which were greater than 3µm, seemed unaffected by meteorological parameters.
Health risk associated with PM concentrations was also calculated for the four sites mentioned above. The highest
risk was observed in the school followed by Janakpuri residential area. The university reported the least health risk.
Keywords: Particulate matter, spatio-temporal variation, indoor-outdoor relationship, regression analysis, risk
assessment
