Water Resources--Office of Water Quality

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## CONVERSION FACTORS, SELECTED TERMS, AND ABBREVIATIONS

### CONVERSION FACTORS

 Multiply By To obtain inch (in.) ` 25.4` millimeter (mm) square inch (in2) ` 645.1` square millimeter (mm2) foot (ft) ` 0.3048` meter (m) gallon (gal) ` 3.785` liter (L) pound, avoirdupois (lb) ` 0.4536` kilogram meter (m) ` 3.281` foot centimeter (cm) ` 0.3937` inch micrometer (µm) ` 3.9372 x 10-5` inch millimeter (mm) ` 0.03937` inch liter (L) ` 0.264` gallon milligrams per liter (mg/L) ` 0.5841` grains per gallon milliliter (mL) ` 0.0338` ounce, fluid milliliter (mL) ` 2.64 x 10-4` gallon milligram (mg) ` 3.527 x 10-5` ounce, avoirdupois gram (g) ` 0.03527` ounce, avoirdupois kilogram (kg) ` 2.205` pound

Temperature: Water and air temperature are given in degrees Celsius (°C), which can be converted to degrees Fahrenheit (°F) by use of the following equation:

ºF = 1.8(ºC) + 32

### SELECTED TERMS

Analyte (target analyte): "Substances being determined in an analysis" (from Bennett, H., ed., 1986). The term "target analyte" is used in this report to refer to any chemical or biological substance for which concentrations in a sample will be determined. Target analyte does not include field-measured parameters such as temperature, conductivity, dissolved-oxygen concentration, pH, Eh, alkalinity, color, or turbidity.

Fluorocarbon polymers: Fluorocarbon polymers (polyfluoro-carbons) are composed of monomers (smallest repeating compound segment of polymer) consisting of carbon, fluorine, hydrogen, and, for one polymer, oxygen also. The fluorocarbon polymers have trade names that include, for example, TeflonTM FEPC (fluorinated ethylene polypropylene), TeflonTM PFA (perfluoroalkoxy), TeflonTM PTFE (polytetrafluoroethylene), KynarTM (polyvinylidene fluoride), and TefzelTM (ethylene tetrafluoro-ethylene). Each fluorocarbon polymer has different chemical and physical properties; however, all are relatively nonreactive chemically at ambient temperatures and do not leach monomers.

Trace element(s): For the purpose of this report and to maintain consistency with common usage, the term "trace element(s)" is used to refer to metals and other elements such as arsenic, antimony, selenium, and tellurium that usually are present in natural surface- and ground-water systems in concentrations less than 1 mg/L (modified from Hem, 1985). Common usage of this term, as defined above, is inexact and not rigorous with respect to aqueous chemistry.

Whole water: Water as sampled from its source and not subjected to filtration or other phase-separation process. Common synonymous terms include: raw (water) sample and unfiltered (water) sample.

### ABBREVIATIONS

 ft/s feet per second mg/L milligram per liter lb/in2 pounds per square inch L/min liter per minute BOD biochemical oxygen demand CFC chlorofluorocarbon FISP Federal Interagency Sedimentation Project, Waterways Experiment Station, Vicksburg, Miss. HCl hydrochloric acid HIF USGS Hydrologic Information Facility, Stennis Space Center, Miss. NFM National Field Manual for the Collection of Water-Quality Data NWQL USGS National Water Quality Laboratory PVC polyvinyl chloride QWSU USGS Quality of Water Service Unit, Ocala, Fla. SPE solid-phase extraction TWRI Techniques of Water-Resources Investigations USGS U.S. Geological Survey VOC volatile organic compounds