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AQS Codes and Descriptions
Unless indicated otherwise, links on this page are to Excel spreadsheets created with Discoverer.
- Agency Codes*
- listed by Name (No Tribes)
- listed within states (No Tribes)
- Tribal Agencies
- City names (by state)
- Collection Frequency Codes
- CBSA (Core-Based Statistical Area) codes - replaces MSA codes
- CSA (Combined Statistical Area) codes - replaces CMSA codes
- CMSAs
- MSAs - sorted by code
- Monitor Types
- Pollutant Standard IDs and Descriptions
- Sample Duration Codes
- Parameters with Sampling Methodologies
- Pollutant (Parameter) Codes
- Parameters with allowed Qualifier Codes
- Parameters with Exceptional Event Qualifiers
- Null Data Codes Old Format
- Qualifier Codes
- State and County codes
- Units - sorted by code
- Units - sorted by description
*Agency Codes are unique to the agency within AQS. If an agency you need already exists, but is not shown for your state, contact NADG to have your state added to the list of states that can use that agency code.
**All parameter codes used by AQS do not have CAS numbers. This table lists only those with CAS numbers.