Indoor-Outdoor Relationship of Suspended Particulate Matter in Riyadh, Saudi Arabia

Abstract

The purpose of this study was to evaluate the suspended particulate matter levels indoors and outdoors in the Engineering Laboratories in the College of Engineering at King Saud University in Riyadh. The total suspended particulate matter (TSP) was evaluated by using standard high volume air samplers and the inhalable particulates (IP) were evaluated by using circular Jet cascade impactors, (IACFM Andersen Samplers). The average TSP for samples taken outdoors was 662 /ug/m 3 while the average TSP indoors was 167 fig/m z. The average indoor-outdoor ratio for TSP was 0.25. The average IP less than 10 /um in size for samples taken outdoors was 137 /ug/m 3 while the average IP indoors less than 10 /urn was 78 fig/m 2. The average indoor-outdoor ratio for IP was 0.59. The average geometric mean size of the IP outdoors was 1.54 fim while indoors the average geometric mean size was 1.33 fim. It would appear that to set air quality standards it would be appropriate to consider both indoor and outdoor exposures.

The Relationships between Indoor and Outdoor Respirable Particulate Matter: Meteorology, Chemistry and Personal Exposure

“…The range of respirable particulate concentrations for indoor and outdoor air was 5-22 and 6-110 ÌgWm -3 , respectively. The mean I/O ratio recorded here is similar to results for fine particulates measured by other researchers: 0.59 [6] and 0.6 [26]. Indoor and outdoor particulate concentrations are significantly correlated, r 2 = 0.31 ( fig.…”

“…However, airborne particulate concentrations can vary significantly over a relatively short distance, for example concentrations near to busy roads may be far higher than background concentrations, especially within street canyons where the dispersion of traffic-related pollutants can be restricted. In addition, many people spend the majority of their time indoors, estimated to be approximately 80-90% of their day [5], and previous research has shown that indoor (I) and outdoor (O) particle concentrations can vary widely [6,7]. It is important to determine how the particle concentration inside a building is affected by changes in outdoor concentrations and how this may relate to the particle levels to which building inhabitants are exposed.…”

Annual and weekly patterns of ozone and particulate matter in Jeddah, Saudi Arabia

“…Although the Kingdom of Saudi Arabia has been identified as exhibiting signs of increased air quality degradation in recent decades, thus far there has been limited analysis of urban and rural pollutant concentrations and trends. Previous studies have shown high concentrations of carbon monoxide (CO) and other pollutants in Jeddah (Nasralla, 1983), elevated PM 10 concentrations in the Saudi capital of Riyadh (Rowe et al, 1985), increasing incidence of asthma (Al Frayh et al, 2001), and elevated CO concentrations in and around the major urban centers of Saudi Arabia (Tangborn et al, 2009), as well as positive trends in O 3 and PM 10 in the city of Meccah (Munir et al, 2013), but a great deal of uncertainty remains in regards to the characterization of Saudi air quality. One obstacle to further analysis has been an absence of high-resolution emission inventories, limiting the efficacy of regional chemical transport models.…”

Poluição do ar e doenças respiratórias: uma revisão

“…Evidenciaram variações ponderáveis nas concentrações de diversos poluentes, durante o dia e à noite, intra e extra-residência, e inter-domicílios. Na Arábia Saudita, Rowe et al (1985) compararam as partículas em suspensão intra e extradomiciliares em Riad. A média de partícu-las em suspensão totais nos ambientes externos foi de 662 microgramas/m 3 , enquanto dentro das casas foi de 167 microgramas/m 3 .…”