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Accurate pH testing reflects water health, ensuring drinking water is safe. If we drink too acidic or alkaline water, we can disrupt the body’s balance and develop harmful bacteria, viruses, and fungi. In an environmental setting, a pH sensor helps to measure if the water is basic or acidic. Changing pH readings can be an early indicator of increasing pollution and degrading water quality.

How Do You Measure pH of Water?

The Waka has a preinstalled combination pH sensor that monitors pH levels every 15 minutes. The combination electro sensor features both a measuring electrode and a reference electrode. The measuring electrode of the pH sensor detects changes in the pH value in the water while the reference electrode delivers a stable signal.

How Does a pH Sensor Work?

pH sensors monitor the level of pH by measuring the activity of the hydrogen ions. The activity is compared to pure water, a neutral solution, using the pH scale of 0 to 14 to determine the acidity or alkalinity.

P H Sensor Water Monitoring Water p H

The pH Scale of Water

The pH of a solution, how acidic or basic it is, is a significant indicator of water quality. Water with more free hydrogen is acidic, compared to water with more free hydroxyl ions is basic. The pH scale of 0 to 14 indicates if water is acidic or alkaline, with pure water sitting at seven on the scale. When the pH value drops below 7, the water becomes more acidic. Whereas, if the number rises above 7, it becomes more alkaline or basic.

pH levels can be affected by chemicals in the water, so pH is an important indicator of water changing chemically. For example, water with a pH of five is 10x more acidic than water with a pH of six. When we drink liquids that are too acidic or too alkaline, it can disrupt the body’s balance, leading to developing bacteria, viruses, fungi and alike.

P H Sensor

Where Are pH Sensors Used?

pH sensors are used in many industries, including chemicals, water and wastewater, and farming and forestry. The sensors used depend on the application. pH sensors are often used in urban environments with hydrothermal activity, meaning that in an environment associated with activity involving hot waters, pH levels can indicate changes in volcanic disturbance.

What are the Different pH Sensors?

There are a variety of different pH sensor options. For the use of liquid measurement, pH sensors include combination, laboratory, process, and differential options.

Combination pH Sensor

The combination option uses a reference electrode and a measuring electrode. The reference electrode provides a stable signal, while the measuring electrode detects changes that occur with the pH value.

Differential pH Sensor

Differential sensors are built from three distinct electrodes, with the third being a metal ground electrode. They are unique as they can prevent reference fouling.

Laboratory pH Sensor

The laboratory option can often include a combination of sensors housed within plastic bodies and 12mm glass. This sensor option is designed for lighter applications like pool monitoring and environmental sampling.

Process pH Sensor

Process pH sensors are made from combination sensors yet are designed and built-in large, durable bodies that include a process connection for continuous pH monitoring.

How Monitoring pH Levels Helps Protect Water Quality

The use of pH sensor probes in water quality management helps understand the water, see changes, and react fast. When pH issues are noticed, we can see what caused these issues. From manufacturing purposes to farming, a good monitoring system in place can produce many benefits like:

  • Reducing water waste

  • Saving energy

  • Meeting sustainability requirements

  • Maintaining a healthy environment

  • Reducing the use of hazardous chemicals

In everyday life, poor water quality can cause significant health concerns. Therefore, a pH sensor plays a critical role in water quality and treatment. When the pH value of a water body becomes too high or too low, the water can be hazardous.

New Zealand Environmental Water Quality Monitoring with Real Time Io T Artificial Intelligence Water Monitor RW

pH Sensors and Water Monitoring Updates

The RiverWatch blog is the data centre for New Zealanders committed to monitoring and enhancing our waterways. Learn more about the water quality of New Zealand and our integral connection with the waters, and stay up to date with important news, research and developments.