The Categories of water, as defined by this document, refer to the range of contamination in water considering both its originating source and its quality after it contacts materials present on the job site. Time and temperature can affect or retard the amplification of contaminants, thereby affecting its category.
- Category One;
- Category one water originates from sanitary water source and does no pose substantial risk from dermal, ingestion or inhalation exposure. Examples: of a category one water sources include, but are not limited to; broken water supply lines; tub or sink overflows with no contaminants appliance malfunctions involving water supply lines; melting ice or snow; falling rainwater; broken toilet tanks or toilet bowls that do not contain contaminants or additives.
- Category one water can deteriorate to category two or three. Category one water that flows into an uncontaminated building does not constitute an immediate change in the category. However, category one water that flows into a contaminated building can constitute an immediate change in the category. Once microorganisms become wet from the water intrusion, depending upon the length of time that they remain wet and the temperature, they can begin to grow in numbers and change the category of the water. Odours can indicate the category one water has deteriorated.
- Category Two;
- Category two water contains significant contamination and has the potential to cause discomfort or sickness if contacted or consumed by humans. Category two water can contain potentially unsafe levels of microorganisms or nutrients for microorganisms, as well as other organic or inorganic matter (chemicals or biological). Examples: of a category two water can include but not limited too; discharge from a dishwasher, washing machines, overflows from washing machines overflows from toilet bowls on the room side on the trap with some urine but not faeces; seepage due to hydro-static pressure; broken aquariums; and punctured water beds.
- Category two water can deteriorate to category three. Once microorganisms become wet from the water intrusions, depending upon the length of time that they remain wet and the temperature, they can begin to grow in numbers and can change the category of the water.
- Category Three;
- Category three water is grossly contaminated and can contain pathogenic, toxigenic, or other harmful agents and can cause significant adverse reactions to humans if contacted or consumed. Examples: of category three water can include but not limited too; sewage, waste-line back flows that originate from beyond the trap regardless of visible content or colour, all other forms contaminated water resulting from flooding from seawater; rising from rivers or streams and other contaminated water entering or affecting the indoor environment, such as wind-driven rain from hurricanes, tropical storms, or other weather-related events if they carry trace levels of contaminants (e.g. pesticides or toxic organic substances).