Chemicals Used in Airplane Water

The drinking water on airplanes comes from public water systems, most of which use a standard series of treatments to remove or neutralize harmful contaminants. However, airline water requires additional testing and disinfection to remain safe for consumption.

Coagulation

• The first process, coagulation, adds alum and iron salts to the public water supply to remove dirt and other particles. These chemicals form sticky particles called "floc," which attract the dirt and then settle out of the water.

Filtration

• The filtration stage removes particles such as clay, natural organic matter, iron and manganese. This step improves the effectiveness of the disinfection process. Some airlines also have their own on-board filtration systems to remove bacteria and chemicals.

Chlorination

• Although public water supplies are usually chlorinated, airplane water generally requires additional disinfection because it comes from a wide variety of sources, and aircraft water lines and holding tanks are prone to contamination. Therefore, the EPA mandates regular testing, flushing and disinfecting of the plane's water systems. The most common disinfection method involves circulating a strong chlorine solution throughout the airplane's water system.

Regulations for Drinking Water on Airplanes

• The Environmental Protection Agency (EPA), Food and Drug Administration (FDA), and Federal Aviation Administration (FAA) jointly regulate the drinking water on airplanes. The EPA regulates public water systems, including the drinking water on planes. The FDA sets standards for water used in cooking and beverages, and for the airport pipes and storage tanks that supply airplanes with water. The FAA regulates the plane's potable water system.