| Acronym | Meaning |
| HRS | Hazard Ranking System |
| PDDO | Projection Of Diatomic Differential Overlap |
| DVB | Diagrammatic Valence Bond (in Study Of Electronic Properties) |
| TD-CAC | Time Dependent-coupled Arrangement Channel (method For Calcns. On Reactive And Dissociative Collisions) |
| DAB | Diaminobenzidine (usually 3,3') |
| STP | Standard Temperature And Pressure |
| ADU | Analog-to-digital Unit |
| ANA | Antinuclear Antibodies |
| GLC | Gas Liquid Chromatography |
| RID | Recrystn. Induced Diffusion |