There are 3 “categories” of water. A “category” is a group of things that have shared characteristics.
Category 1 water is freshwater. It is water that comes from a clean source. This is water that you can usually contact and drink. Examples of cat 1 would be rainwater, plumbing supply lines, tub or sink overflows with no contaminants, melting ice or snow, broken toilet tanks and more. Category 1 water can come into contact with bacteria or mold which would classify the water as category 2 or 3 water. Category 1 water is also classified as category 2 or 3 water if it remains stagnant in a space for 24 – 48 hours.
Category 2 water is gray water. This is water that if you contact or drink it, you would get sick. Examples of cat 2 are dishwasher machine discharge or overflow, toilet bowl overflow with urine, broken aquariums, water beds, sink drain water or shower drain water. Category 2 water, if left untreated for 2 days or more becomes category 3.
Category 3 water is black water. You cannot come into contact with or drink black water without becoming extremely sick or dying. Examples of cat 3 water are sewage, flooding seawater, septic backup, groundwater or rainwater caused from hurricanes or tropical storms.