| Abbreviation | Definition |
|---|---|
| APE | Area of Potential Effect |
| APEC | A Permanent Environmental Crisis |
| APEC | Alley Pond Environmental Center |
| APECS | Aircrew Personal Environmental Control System |
| APES | Advanced Placement Environmental Science |
| APH | Asbestos Pollution and Health |
| APHIP | Air Pollution and Health Impacts Project |
| API | Antecedent Precipitation Index |
| APIMS | Air Program Information Management System |
| APINA | Air Pollution Information Network for Africa |
| APIS | Air Pollution Information System |
| APN | Assessor Parcel Number |
| APNEG | Asia Pacific Network for Environmental Governance |
| APPC | Abuse of Plant- Protections Chemicals |
| APPCB | Andhra Pradesh Pollution Control Board |
| APPCB | Andhra Pradesh Pollution Control Board (India) |
| APPCD | Air Pollution Prevention and Control Division |
| APRG | Air Pollution Research Group |
| APS | Air Purification and Sterilization |
| APTB | Air Pollution Technology Branch |