The average indoor concentrations of fine particles less than 2.5 mm (PM2.5) in the residential
areas ranged from 37.1 mg/m3 (±5.8 mg/m3) to 45.2 mg/m3 (±5.3 mg/m3), while indoor PM2.5
concentrations in centers with roadways nearby ranged from 48.9 mg/m3 (±9.5 mg/m3) to 52.9 mg/m3
(±7.7 mg/m3), and up to 51.1 mg/m3 (±6.4 mg/m3) in residential areas located near construction sites.