Testing for safe water | Infrastructure news

Safe water is not harmful. Commonly used to describe drinking water, safe water can also apply to water for swimming or other uses. To be safe, the water must have low concentrations of harmful contaminants. The Blue Drop Kit helps to determine if water is safe. 

The Hanna Instruments Blue Drop Kit comprises:  

• HI98703-02 – portable turbidity meter . 

• HI97711C – free and total chlorine photometer kit. 

• HI93701-01 – free chlorine reagents (100 tests).  

• HI93711-01 – total chlorine reagents (100 tests). 

• HI98195 – multiparameter portable meter that measures pH, ORP, EC/TDS, resistivity, salinity, seawater and temperature. 

Portable turbidity meter (HI98703-02) 

Turbidity is one of the most important parameters used to determine the quality of drinking water. Once considered as a mostly aesthetic characteristic of drinking water, significant evidence exists that controlling turbidity is a competent safeguard against pathogens. In natural water, turbidity measurements are taken to gauge general water quality and its compatibility in applications involving aquatic organisms. 

The monitoring and treatment of wastewater was once solely based on the control of turbidity. Currently, the measurement of turbidity at the end of the wastewater treatment process is necessary to verify that the values are within regulatory standards. 

The HI98703 precision turbidity portable meter is specially designed for water quality measurements, providing reliable and accurate readings, especially in the low turbidity range. The instrument is based on an optical system that guarantees accurate results, assures longterm stability, and minimises stray light and colour interferences. Periodic calibration with the supplied standards compensates for any variations in intensity of the tungsten lamp. The 25 mm round cuvettes composed of special optical glass guarantee the repeatability of turbidity measurements. 

The AMCO AEPA-1 supplied standards are recognised as a primary standard by the USEPA. The standards are reusable and stable with a long shelf life. The sensitivity of the instrument should permit detection of a turbidity difference of 0.02 NTU or less in waters having turbidities less than 1 unit. 

Free and total chlorine portable photometer (HI97711C) 

As one of the most common forms of disinfectants used, chlorine improves water quality by destroying disease-producing microorganisms and by reacting with other organic and inorganic substances. Chlorine levels must be actively monitored to ensure sufficient chlorine is present for disinfection, as well as to control adverse effects such as taste, odour and potential reactions with organic matter to form harmful disinfection by products. Chlorine is used by many due to its disinfection, oxidation and bleaching properties. It is used in swimming pools, drinking water and food processing to disinfect and keep bacteria from growing. 

The optical system offers superior performance in accuracy and repeatability, and only needs a short amount of time to perform a measurement. Its compact, waterproof meter is user-friendly with a tutorial mode that walks the user graphically, step by step, through performing a measurement. The HI97711 is completely waterproof, including the cuvette holder that is designed with ridges to protect the optical path from getting scratched by the cuvette. 

Multiparameter portable meter (HI98195) – pH, ORP, EC/TDS, resistivity, salinity, seawater and temperature 

salinity, seawater and temperature The HI98195 monitors up to 10 different water quality parameters (five measured and five calculated). The microprocessorbased, multisensor probe allows for the measurement of key parameters including pH, ORP, conductivity and temperature. The probe transmits readings digitally to the meter, where data points can be displayed and logged. The complete system is simple to set up and easy to use.  

The HI98195 is supplied with all necessary accessories and packaged in a durable carrying case, designed to provide years of use. The inside compartment of the carrying case is thermoformed to securely hold and protect all the components. Enclosed in an IP67-rated waterproof casing, the meter can withstand immersion in water at a depth of 1 m for up to 30 minutes. The probe features an IP68 rating for continuous immersion in water. Sensor replacement is quick and easy, with field-replaceable, screw-type connectors that are colour-coded for easy sensor port identification. The probe and meter automatically recognise the sensors that are connected. Any ports not used on the probe will not have the parameter displayed or be configurable. Its rugged, waterproof design makes it ideal for field use. 

The pH of water is a measure of how acidic/basic water is. The range goes from 0 to 14, with 7 being neutral. A pH of less than 7 indicates acidity, whereas a pH of greater than 7 indicates a base. The pH of water is a very important measurement concerning water quality. The pH of most drinking water lies within the range of 6.5 to 8.5. 

Electrical conductivity (EC) of water refers to how water is able to conduct electricity. Generally, dissolved solids in water determine the electrical conductivity. EC is the measurement of the ionic process of a solution that enables it to transmit current. According to WHO standards, EC value should not exceed 400 μS/cm. It is important to understand that the electrical conductivity of water should be measured for a variety of different reasons. EC in drinking water should be less than 1 mS/cm. When working in the pharmaceutical industry, the EC of water will need to be even lower and should be less than 1 uS/cm. Because seawater has an ample amount of salt and other chemicals within it, the measurements of this water will typically come in at 45-72 mS/cm. Water with a salinity of 0-17 ppt is called brackish water that is commonly found in estuaries and marshes. Some estuaries have a salinity of up to 30 ppt. Seawater is on average 35 ppt but can go up to 40 ppt. 

Ultrapure water has an exceedingly high resistivity reading of 20 million ohms, which essentially means that there are no dissolved solids or contaminants in the water. With this reading, one can be confident that the water is pure and safe to drink. 

Click here to find out about Hanna Instrument’s participation at the WISA conference: ON THE GO WITH HANNA INSTRUMENTS AT WISA 2022 CONFERENCE AND EXHIBITION – YouTube

Additional Reading?

Request Free Copy