Emissions Factors and Calculation Methodologies

• AP-42: EPA's compilation of air pollutant emissions factors
• WebFIRE Emissions Factor Search
• EIIP: EPA's Emission Inventory Improvement Program

Emissions Models

• Landfill gas emissions model
• TANKS storage tank emissions model
• WATER9 wastewater treatment plant mode

Codes

• Standard Industrial Classification (SIC) codes
• Source Classification Codes (SCC)
• Chemical Abstract Services (CAS) codes
• North American Industry Classification System (NAICS)