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R9 Laboratory SOP 1067
CALIBRATION AND OPERATION OF REFRACTOMETERS
Summary
The purpose of this standard operating procedure (SOP) is to describe procedures for the measurement of salinity using a refractometer. Salinity is the total amount of salts dissolved in seawater. Refractometers measure the change in the direction of light as it goes from air to water to measure salinity.
This SOP is applicable to the measurement of salinity in environmental and surface water samples, particularly estuarine and marine samples. The SOP is to be followed whenever salinity measurements are made, either in the toxicity lab or in the field.