In this study, we aimed to carry out a comprehensive investigation of particulate matter less than 10 m in aerodynamic diameter (PM10) among industrial, residential and ecologically sensitive sites in the Western Himalayan region. To achieve this goal, PM10 data from 20 stations were used to describe the spatial and temporal patterns. To determine the potential sources of pollution, we constructed a bivariate polar plot based on wind speed and direction. Overall, our findings showed that only ecologically sensitive sites had lower PM10 (59.02 ± 34.77 μg/m3) than the National Ambient Air Quality Standard of 60 μg/m3. Both industrial (115.9 ± 47.82 μg/m3) and residential sites (87.16 ± 35.83 μg/m3) had higher PM10 concentrations; the highest concentration level occurred during the winter season, and the lowest concentration level occurred during the monsoon season of the same year; the concentrations exceeded the national standard. At each site, emission sources both within and outside the state were categorized based on the bivariate polar plot. Industrial and vehicular emission, biomass and solid waste burning, dust from a nearby unpaved road, and long-range transport pollution contributed to air quality deterioration in the state. Moreover, the monsoon season significantly affected air quality. In this study, we concluded that the PM10 concentration in Himachal Pradesh exceeded the limit indicated in the World Health Organization (WHO) guidelines and worsened because of local industrial and traffic pollution and long-range transport.