| Acronym | Meaning |
| RCIOSA | Reactive Classical-infinite-order-sudden Approxn. |
| IEG | Immediate Early Gene |
| PISA | Pharmaceutical Information Systems Association |
| OMNMHCE | Organic Material Nonmethane Hydrocarbon Equivalent |
| AAU | Amendment To Allege Use |
| G1 | Gaussian-one (theory For Calcg. Mol. Energies) |
| APCI | Atm. Pressure Chem. Ionization |
| HRS | Hazard Ranking System |
| ZI | Zero Intercept |
| BNR | Biological Nutrient Removal |