| Acronym | Meaning |
| HRS | Hazard Ranking System |
| NAPBN | National Air Pollution Background Network |
| SCCF | Self-consistent Crystal Field (method For Calcns. On Molecular Crystals) |
| HRE | Hormone-responsive Element |
| BPCT | Best Practicable Control Technology |
| WNV | West Nile Virus |
| CLC | Clean Lakes Clearinghouse |
| CCMET | Coupled-cluster Many-electron Theory |
| IAVCEI | International Association Of Volcanology And Chemistry Of The Earth's Interior |
| BMR | Basal Metabolic Rate |