ATS	American Thoracic Society
COPD	Chronic Obstructive Pulmonary Disease
ERS	European Respiratory Society
FEV1	Forced Expiratory Volume in one second
FVC	Forced Vital Capacity
AOR	Adjusted Odds Ratio
PEF	Peak Expiratory Flow
PFTs	Pulmonary Function Tests
PM2.5	Fine Particulate Matter
RIHES	Research Institute for Health Sciences
WHO	World Health Organization