The resultant color of the mixture is then compared with a reference scale. Special high class filter papers impregnated with suitable indicator solutions can be submerged into the unknown solution and the resultant color of the paper is compared with a reference scale. The indicator papers are a simple method of determining a broad assay of acidity or alkalinity. They are not as precise as the other methods. Professional carpet cleaners select carpet cleaning agents with pH's between 7 and 10 to avoid potential carpet damage.
Agricultural specialists control soil pH to enhance plant growth.
Laundry experts keep the pH above 9.5 during the bleach cycle to protect fabrics from bleach attack. Industrial plants control the release of sulfur dioxide to control harmful acid rain from damaging our environment. It is important for every cleaning professional to have a basic understanding of pH. Ignoring the pH of a solution can be expensive. Floor coverings and surfaces can be damaged by an inappropriate pH value. Be careful and select cleaning products with compatible pH values to match your surface requirements.