Air Quality Resources

Resources, links and tools to help you understand and comply with air quality regulations affecting your natural gas use.

Air Districts in the SoCalGas® Service Territory

The California Air Resources Board (CARB) provides a map that will help you identify the various Air Districts in California. This map is available from the CARB map page which contains other helpful maps:

Access the CARB mapping page *

Air Quality Services Brochures

South Coast Air Quality Management District (SCAQMD) Rules

Guaranteed Permitting Program

Certified Source Testers

Source testing is often required in order to comply with many of the rules and regulations imposed by air quality agencies. To make sure the testing is acceptable, the source tester needs to be certified by a qualified agency, such as CARB.

Search a list of certified source testers* courtesy of the California Air Resources Board.

Technical Assistance

For technical assistance, use the AQ Answerline - Dial 1-562-803-7428 to get personalized assistance with your facility's air quality questions. Find out about current regulations, emission control requirements, emission factors, permitting requirements or other issues you are concerned about.

In addition, we can send you the following information via email:

  • Text of federal, state and local air regulations
  • Copies of air district forms
  • Best Available Control Technology (BACT) guidelines
  • Lists of environmental contractors and equipment vendors
  • Emission factors
  • Details of available emission reduction credits
  • Air Quality Assistance Brochures (Permitting, Boiler, and Engine Compliance) developed by SoCalGas
  • Referrals for further assistance

Title V

The Title V Permit system is the air pollution control permit system required to implement the federal Operating Permit Program as required by Title V of the federal Clean Air Act as amended in 1990. This regulation defines permit application and issuance procedures as well as compliance requirements associated with the program.

Learn more about applicability to Title V in the SCAQMD.

Unit Conversion Tools

The following unit conversion tools will help you meet SCAQMD rules and regulations:

Internal Combustion (IC) Engine Emissions

Manufacturers of IC engines typically quote emissions in units of grams of pollutant/bhp-hour.

However, regulators (such as the South Coast Air Quality Management District) typically specify IC engine emissions in either ppm of pollutant @ 15 percent O2 or ppm of pollutant @ 3 percent O2. You can easily perform the conversion back and forth for various types of pollutants (such as NOx, CO, and ROG) by downloading the IC Engine Emissions Spreadsheet (Microsoft Excel format).

Water Heater Emissions

Manufacturers of water heaters typically quote emissions in units of ppm of pollutant @ 3 percent O2.

However, regulators (such as the South Coast Air Quality Management District) typically specify water heater emissions in nanograms of pollutant/joule of useful work. You can easily perform the conversion back and forth for various types of pollutants (such as NOx, CO, and ROG) by downloading the Water Heater Emissions Spreadsheet (Microsoft Excel format)