| Acronym | Definition |
|---|
| IRRS➣Integrated Regulatory Review Service (International Atomic Energy Agency) |
| IRRS➣Irish Railway Record Society (est. 1946) |
| IRRS➣Italian Radio Relay Service |
| IRRS➣International Regulations Retrieval System (USDA) |
| IRRS➣Institute of Radiation and Remote Sensing (University of California, Los Angeles) |
| IRRS➣Individual Ready Reserve System |
| IRRS➣International Rail Road System (British Columbia, Canada) |