Experimental Assessment of Natural Ventilation as a Mitigation Measure for Indoor Air Pollution Problem

Abstract

AbstractIndoor air quality is dependent on numerous factors such as the number of active indoor pollution sources, penetration of outdoor air, building location and the ventilation system in the building. The less ventilated indoor environment leads to dangerous accumulation of PM and hence higher exposure doses to the occupants. Natural and mechanical ventilation plays a major role in diluting the indoor air pollutants. This study aims to quantify the impact of natural ventilation in improving the indoor air quality. The built-up of indoor air pollutants with four indoor air pollution sources was studied in a non-ventilated environment in an indoor air testing unit setup. Air quality was further monitored with the same setup in naturally ventilated environment and the adjacent outdoor. A 31-channel laser spectrometer GRIMM 11 R (MIN-LAS) was used for the continuous real-time measurements of 0.25–32 µm sized PM. The average daily dose to the exposed population was estimated for both the ventilation conditions. It was found that natural ventilation resulted in reducing the indoor PM by 80–90%. The reduction in concentrations ranged from 86 to 90% for PM10, 87–91% for PM2.5, and it was 91–93% for PM1. The reduction in fine particulates PM1 was found to be more as compared to the other studied particulates. The quantification of health risk from exposure to PM2.5 was carried out by estimating the potential dose to the receptor. The daily dose of 67 mg/kg-day for the 6–11 years age group attributed to PM10 was decreased to 7.4 mg/kg-day with the ventilation. Hence, in the regions where outdoor air is not polluted, natural ventilation can be an effective mitigation measure for the indoor air pollution and associated health problem.KeywordsIndoor air pollutionParticulate matterNatural ventilationAverage daily dose