title: Particle size distribution and air pollution patterns in three urban environments in Xi'an, China.
abstract: Three urban environments, office, apartment and restaurant, were selected to investigate the indoor and outdoor air quality as an inter-comparison in which CO2, particulate matter (PM) concentration and particle size ranging were concerned. In this investigation, CO2 level in the apartment (623 ppm) was the highest among the indoor environments and indoor levels were always higher than outdoor levels. The PM10 (333 µg/m(3)), PM2.5 (213 µg/m(3)), PM1 (148 µg/m(3)) concentrations in the office were 10-50% higher than in the restaurant and apartment, and the three indoor PM10 levels all exceeded the China standard of 150 µg/m(3). Particles ranging from 0.3 to 0.4 µm, 0.4 to 0.5 µm and 0.5 to 0.65 µm make largest contribution to particle mass in indoor air, and fine particles number concentrations were much higher than outdoor levels. Outdoor air pollution is mainly affected by heavy traffic, while indoor air pollution has various sources. Particularly, office environment was mainly affected by outdoor sources like soil dust and traffic emission; apartment particles were mainly caused by human activities; restaurant indoor air quality was affected by multiple sources among which cooking-generated fine particles and the human steam are main factors.
authors.affiliation: School of Human Settlements and Civil Engineering, Xi'an Jiaotong University, Xi'an, China. jilltalent@126.com.|School of Key Lab of Aerosol Science and Technology, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710075, P.R China. jilltalent@126.com.
authors.forename: Xinyi
authors.initials: X
authors.lastname: Niu
authors.affiliation: Observatory Midi-Pyrenees, National Center for Scientific Research, Toulouse, France. benjamin.guinot@gmail.com.|School of Key Lab of Aerosol Science and Technology, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710075, P.R China. benjamin.guinot@gmail.com.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Guinot
authors.affiliation: School of Key Lab of Aerosol Science and Technology, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710075, P.R China. jjcao@ieecas.cn.|Institute of Global Environmental Change, Xi'an Jiaotong University, Xi'an, China. jjcao@ieecas.cn.
authors.forename: Junji
authors.initials: J
authors.lastname: Cao
authors.affiliation: School of Key Lab of Aerosol Science and Technology, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710075, P.R China. xuhongmei@ieecas.cn.|Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an, China. xuhongmei@ieecas.cn.
authors.forename: Hongmei
authors.initials: H
authors.lastname: Xu
authors.affiliation: Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an, China. csunjian@gmail.com.
authors.forename: Jian
authors.initials: J
authors.lastname: Sun
mesh_terms: D016902:Air Pollution, Indoor / Q000032:analysis*; D002245:Carbon Dioxide / Q000032:analysis*; D002681:China; D002947:Cities; D004784:Environmental Monitoring; D010316:Particle Size; D052638:Particulate Matter / Q000032:analysis*; D017132:Workplace
chemical_list: D052638:Particulate Matter; D002245:Carbon Dioxide
keywords: Carbon dioxide; Indoor air quality; Particle mass; Particle size distribution