Around the world, pH is the most widely tested chemical parameter.
From pH paper to popular pH meters, several methods are available for measuring this parameter. pH is measured for various processes including environmental monitoring, pharmaceutical production, scientific research, electronics manufacturing, and many other applications. For example, in textile processes, pH control is critical in ultimately impacting the quality of material and costs.
Methods used to measure pH
Using papers are an inexpensive method that provides an indication of acidity or alkalinity but not an accurate measurement. Using an organic dye, this coated paper changes color to indicate the presence of acid or base. Easy to use, the litmus papers are only for noncritical measurements.
pH meters are the most accurate type of measurement and are widely used. Pocket-sized meters called testers are small, easy to use for fieldwork and relatively low cost. One step above the testers is handheld, portable meters. These often include additional features and can be found in laboratories as well as in field use. For stationary lab applications, benchtop meters provide more substantial data management and show readings on larger displays. ISFET (ion specific field effect transistor) meters have a silicon chip sensor rather than glass bulb electrodes. These meters are more often used in food production.
These handy instruments most commonly measure pH, conductivity, dissolved oxygen, temperature, depth, turbidity, barometric pressure, and salinity. They can take accurate measurements of many substances simultaneously. As advanced water quality meters, they include added features which enhance convenience.