Particulate matter and carbon dioxide monitoring in indoor places

Abstract

People spend most of their time in enclosed spaces (e.g., apartments, offices and public buildings). According to research, indoor air quality can be worse than the outdoor air quality (OAQ). Hazardous chemicals found in the air indoors can adversely affect the functioning of the human body and cause many respiratory and circulatory diseases. Little is known about particulate matter (PM) concentration in indoor space of various services and office buildings/facilities (not related to production, i.e. offices, shops, kitchens etc.) and its associated health risk. Similarly, carbon dioxide (CO2) is a gas scarcely analyzed in the buildings but it is a good marker of living comfort. In this study, measurements of PM and CO2 were taken in indoor environments, poorly investigated in the past. The concentrations of PM were monitored and compared using a GRIMM analyzer model 1.108 in two offices, two printer rooms and two bedrooms, while the levels of CO2 were investigated by means of a Sensordrone low-cost multi-sensor in a computer-room, in addition to the same offices and bedrooms already under study. The indoor PM concentration was certainly influenced by outdoor levels but human activities played a key role causing a worsening of indoor air quality. The concentration decrease rates of fine particles (the most harmful) were lower than those of the coarse fraction; therefore, the effects were still appearing even after the end of the activities that generated it. According to the latest guidelines, the average concentrations of CO2 measured between 990 ppm and 1,318 ppm suggested a low standard of comfort of building occupants, which may suffer from headaches, drowsiness and attention deficit. In recent years, the portable sensors have produced a great potential in creating extended monitoring networks in real time; however, a progress in reliability of data is needed.