Onsite measurement is necessary to preserve sample integrity and ensure data accuracy for the following field measurements: water temperature, dissolved-oxygen (DO) concentration, specific electrical conductance (SC), pH, and reduction-oxidation potential (redox/ORP).
A variety of single-parameter and multiparameter field-measurement instruments are available that use various technologies to measure the same water property and that require differing calibration, maintenance, and measurement methods.
|YSI Multiparameter Datalogging Sondes|
Multiparameter instruments that contain sensors (each specific to the measurement of a given physical, chemical, or biological property) that are bundled in a single housing (a sonde) and deployed in environmental waters.
Advantages of Multiparameter Sondes:
|Portable Turbidity Meters|
Turbidity, which can make water appear cloudy or muddy, is caused by the presence of suspended and dissolved matter, such as clay, silt, finely divided organic matter, plankton and other microscopic organisms, organic acids, and dyes. The color of water, whether resulting from dissolved compounds or suspended particles, can affect a turbidity measurement.
The following are examples of the uses for turbidity data:
|WaterLOG® Data Logging & Hydro-Meteorological Sensors|
WaterLOG® is a world leader specializing in manufacturing precision water level instrumentation, and data logger telemetry systems for hydrological and meteorological measurements. They provide a broad range of innovative equipment capable of reliable measurements in extremely harsh conditions. Instrumentation applications range from flood warnings, surface water, storm water, ground water, irrigation, meteorology and many others. Customers are hydro-meteorologists, scientists and anyone who needs to collect water level measurement in a range of applications.
|Seametrics Water Quality Sensors|
Often the changes in water measurements are more important than the actual measured values. Depending on the manufacturer, some instruments can store instantaneous or continuous measurements to internal or external memory in a format compatible with a hand-held display, personal digital assistant (PDA), or laptop computer.
|Colorimeters, Photometers and Test Strips|
Colorimeters and Photometers are used to analyze samples of water, suspended sediment, and bottom material for their content of inorganic and organic constituents.
In general, a colorimetric procedure involves adding some type of chemical (or “reagent”) to a sample of water. The reagent then reacts with the substance we are trying to measure, causing a color change in the sample.
The following are applications of Colorimetric analysis:
|Calibration Buffers, Standards, Reagents and Cleaners|
Reference materials whose properties have been established so that it can provide a level of performance verification. For field measurements, examples are pH buffers, specific conductivity standards, chemical reagents, turbidity standards and oxidation reduction potential standards.
Field instrumentation require supplies for the actual collection process as well as quality control activities and crucial operational maintenance.