Water is classified into 3 categories to identify if the source of water contains a potential threat to humans. i. CAT 1 Water- Refers to a source of water that does not pose a hazard if consumed by humans. This often refers to leak in water pipes or another clean source of water, but if this water source becomes in contact with other materials (walls, flooring, decking) it has a potential to become contaminated with the soils within those materials. Once this occurs it will progress to the following category. ii. CAT 2- Refers to a source of water that contains some degree of contamination that may cause an illness if consumed by humans. iii. CAT 3- Refers to source of water that is grossly contaminated that will cause death or serious illness if consumed by humans. All sewage and most natural disasters are considered CAT 3.