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AQDx Standard Format Guidance
Unit Codes
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AQDx Standard Format Guidance
Introduction
Quick Start Guide
Data Field Definitions
Data Field Definitions
Field Dictionary
Data Types & Conventions
Data File Formats
Data File Formats
Tabular Files (CSV/Excel)
JSON & Streaming
Metadata Guidance
Metadata Guidance
Overview
Code Lookup Tables
Code Lookup Tables
Parameter Codes
Method Codes
Measurement Technology Codes
Unit Codes
Qualifier Codes
Supplemental Codes
Appendices
Appendices
Glossary
Version Changelog
Copied from US EPA AQS Feb 2026