Investigation of Indoor Particulate Matter (PM) Level in Office Buildings in the UAE

Abstract

The air around us is a mixture of many elements from different states. The particulate matters are suspended particles in the air, which are in liquid or solid state. These particulate matters have a major impact on human health. Due to their size, they can be inhaled and penetrate through the respiratory system, causing allergies, diseases or in extreme cases, it can cause death. This study focuses on investigating the concentration of indoor particulate matter in office buildings in the United Arab Emirates. Two offices in Dubai, the heart of the industrial hub, had been selected for the study. An online questionnaire had been distributed to the office workers, to collect information about the space. Participants from office A had shown some symptoms of difficulty in concentration, running nose, burning of eyes, dizziness, and difficulty in sleeping. Whereas in office B, the results of the questionnaire had indicated a rise in the symptoms experienced than in office A. The PM concentration had been measured at morning, noon and afternoon for each office, for two consecutive days. These results were compared with the international standard levels set by the World Health Organization. In office A, the PM2.5 concentration were 4.292 µg/m3 (morning), 4.690 µg/m3 (noon) and 3.735 µg/m3 (evening). Whereas in office B, the PM2.5 concentration were 82.619 µg/m3 (morning), 75.634 µg/m3 (noon) and 56.851 µg/m3 (evening). Unlike office B, office A were within the recommended 24-hour air quality guideline (AQG) level stated by the WHO for PM2.5 which is 15 µg/m3. For PM10 concentration in office A, it was 32.78 µg/m3 (morning), 19.71 µg/m3 (noon) and 8.63 µg/m3 (evening). While in office B, the PM10 concentration were 133.083 µg/m3 (morning), 100.661 µg/m3 (noon) and 59.490 µg/m3 (evening). Based on the results, PM10 concentration in office A were within the recommended 24-hour AQG level for PM10 which is 45 µg/m3. There were many factors that had led the PM concentration in office B to be high, including the office building being located in an industrial district and the use of split system air conditioning which cools only the air without exhausting the air pollutants in the space. The author had further investigated the particle count emitted by the common sources of air pollutants in an office space, which are the human and the computer. Based on the measurements and calculations, the PM2.5 particle count emitted by the human is 35 particles per minute as an approximate. While for the computer, a total of 10 particles of PM2.5 is emitted per minute. For particles which are larger in size (PM10) they were emitted by the human with a total of 1 particle per 2 minutes and 18 seconds.