The Hanna Instruments HI 98713-11 turbidity calibration standards kit is used for calibrating a turbidity meter at four points. The kit consists of <0.1, 15, 100, and 750 Nephelometric Turbidity Units (NTU) primary standards in calibration cuvettes. The HI 98713-11 is an accessory for use with the Hanna Instruments HI 98713 portable turbidity meter, which is used to test drinking water and ambient water to meet government standards, and to monitor water used in the manufacture of food and beverages.

Turbidity meters (also called turbidimeters) determine the concentration of solids in a sample of liquid (usually water). Turbidity is the cloudiness of a liquid caused by the presence of suspended solids (particles) that may include microorganisms, yeast, or sediment. Turbidity meters indirectly determine the concentration of these solids by measuring the light scattered by particles in the sample. Turbidity meters are commonly used to test drinking water, environmental water, and water used for food and beverages for compliance with government standards.

Hanna Instruments manufactures analytical instrumentation and supplies, including pH meters, electrodes, chemical reagents, and buffer solutions. The company, founded in 1978 and headquartered in Woonsocket, RI, meets International Organization for Standardization (ISO) standard 9001.