Water testing is a vast field, encompassing a wide variety of procedures to determine the quality of water. Millions of tests are performed each day to meet regulatory standards and ensure public safety. These procedures range from simple to complex and are essential to the continued health and safety of society. There are many different types of water testing, from pH and dissolved oxygen to conductivity and color.
Test strips
Test strips for water quality testing are extremely affordable and are easy to use. Chemical strips can detect various contaminants and change color when they are present in water. The colors can be used to determine the amount of metals, chemicals, pesticides, or coliform in water. These tests are inexpensive and can provide results almost instantly. Moreover, they can also provide the chain of custody and sampling information.
Color disks
The use of color disks for water testing can help determine the purity of water. These discs are held in metallic tubes and an operator looks at them through the tubes. When a disc matches a sample, it gives the operator the number of color units. Color disks are commonly used for water testing, and are widely available. Alternatively, an electrode-based pH meter can be used to monitor the pH level of water.
Digital meter
When you’re looking for a quality digital meter for water testing, you may want to choose a meter that water testing measures both electrical conductivity and total dissolved solids. These two measurements are necessary for determining whether or not your water has too much TDS. Fortunately, there are several types of meter that can help you get the exact results you need.
Conductivity meter
Conductivity meters measure water’s electrical conductivity. They use a voltage applied between electrodes in a probe and a standard solution. The resistance of water results in a drop in the voltage, which is used to calculate the conductivity per centimeter. The measurement is then converted by the meter into micromhos per centimeter. Some conductivity meters also test for total dissolved solids. To calculate the concentration of dissolved solids, multiply the measured conductivity by a factor of 0.55 or 0.9.
Coliform tests
Coliform tests in water testing are performed to detect the presence of bacteria that may cause disease. The total coliform bacteria count in the water sample is the primary indicator of the presence of disease-causing organisms. However, a positive result does not mean that a water supply is harmful to humans. Instead, it provides a clue as to how the water is contaminated.
Guidelines for acceptable or unacceptable concentrations
There are guidelines for what is considered acceptable and unacceptable for various contaminants in water. These standards are divided into three categories: health risks, general indicators, and nuisances. The guidelines are not exhaustive, but they provide general limits for a variety of pollutants, along with information on their sources, symptoms, and effects. The guidelines are summarized in Table 1.