| Units of measure |
| C | Celsius |
| mg/L | milligrams per liter |
| µg/L | micrograms per liter |
| µS/cm | microsiemens per centimeter at 25 degrees Celsius |
| Analytical Methods |
| ASF | micro-Kjeldahl digestion, automated segmented flow, colorimetric |
| COL | colorimetric |
| CV-AAS | cold vapor-atomic absorption spectrophotometry |
| DCP-AES | direct current plasma-atomic emission spectrometry |
| DIS | dissolved |
| ELEC | electrometric |
| F-AAS | flame-atomic absorption spectrophotometry |
| GF-AAS | graphite furnace-atomic absorption spectrophotometry |
| GRAV | gravimetric |
| HG-AAS | hydride generation-atomic absorption spectrophotometry |
| IC | ion chromatography |
| ICP-AES | inductively coupled plasma-atomic emission spectrometry |
| ICP-AES/T | inductively coupled plasma-atomic emission spectrometry, trace |
| ICP-MS | inductively coupled plasma-mass spectrometry |
| ISE | ion-selective electrode |
| LL | low level |
| LRL | laboratory reporting limit |
| TITR | electrometric titration |
| USEPA | U.S. Environmental Protection Agency method |
| WWR | whole-water recoverable |
| Others |
| BSP | Blind Sample Project |
| Fs | regression estimate of F-pseudosigma |
| LOP | statistically significant lack of precision |
| MPV | most probable value |
| MRL | minimum reporting limit |
| NEG | negative bias |
| NSD | number of standard deviations |
| NWIS | National Water Information System |
| NWQL | National Water Quality Laboratory |
| POS | positive bias |
| QWSU | Quality of Water Service Unit |
| RSD | relative standard deviation |
| SRWS | standard reference water sample |
| USGS | U.S. Geological Survey |