Use ctrl + F (Windows) or command + F (Mac) to quickly search for an abbreviation. Can't find an abbreviation you're looking for? Send an email to support@theairqualityconsultant.com and we'll help you out!


  • EPA = Environmental Protection Agency
  • HAP = Hazardous Air Pollutant
  • NOx = Oxides of nitrogen
  • SO2 = Sulfur dioxide
  • PM = Particulate matter
  • PM10 = fine particulate matter, particles 10 micrometers and smaller
  • PM2.5 = fine particulate matter, particles 2.5 micrometers and smaller
  • VOC = Volatile organic compounds
  • CO2 = Carbon dioxide
  • CH4 = methane
  • N2O = Nitrous oxide
  • NESHAP = National Emission Standards for Hazardous Air Pollutants
  • NAAQS = National Ambient Air Quality Standards
  • AAQS = Ambient Air Quality Standards
  • PAE = Potential actual emissions
  • BAE = Baseline actual emissions
  • ER = Emission rate
  • CEMS = Continuous emission monitoring system
  • CAM = Compliance Assurance Monitoring
  • TVOP = Title V Operating Permit
  • O3 = Ozone
  • CFR = Code of Federal Regulations
  • PSD = Prevention of Significant Deterioration
  • NSR = New Source Review
  • GHG = Greenhouse gas
  • GHG MRR = Greenhouse gas mandatory reporting rule
  • tpy = tons/year
  • lb/hr = pounds per hour
  • BACT = Best Available Control Technology
  • RACT = Reasonably Available Control Technology
  • LAER = Lowest Achievable Emission Rate
  • ESG = Environmental, Social, and Governance
  • ppm = parts per million
  • ppmv = parts per million, by volume