What "Category 3" means
The water damage restoration industry, following the IICRC S500 standard, classifies water by contamination level. Category 1 is clean water, such as a supply line break. Category 2 contains significant contamination, such as washing machine overflow. Category 3 is grossly contaminated water that can contain pathogens and harmful agents: sewage, toilet backflow from beyond the trap, rising floodwater from rivers or streams, and water that has sat long enough to become contaminated.
Category 3 water changes how cleanup is done. Porous materials it reaches, such as carpet, pad, drywall, insulation and upholstered furniture, generally can't be cleaned and dried in place. They have to be removed.
How Category 3 cleanup works
- Stop the source with your plumber or utility.
- Protect people. Keep occupants, especially children, older adults and anyone with weakened immunity, away from affected areas.
- Extract standing water and sewage.
- Remove affected porous materials, typically including carpet and pad, drywall to above the wet line, insulation and contaminated contents.
- Clean and disinfect remaining structural materials, such as studs, subfloor and concrete.
- Dry the structure with dehumidifiers and air movers, coordinated with your water restoration contractor if one is involved.
- Verify with moisture readings and visual inspection.
- Document for insurance.
Time matters
The longer sewage and contaminated water sit, the deeper they soak in and the more likely mold growth becomes. Start mitigation as soon as possible.
Common questions
Can carpet be saved after sewage?
Industry standards generally call for removing carpet and pad affected by Category 3 water. Some hard surfaces and structural materials can be cleaned.
Is it safe to stay in the house?
Stay out of affected areas. If sewage affected large areas or living spaces, temporary relocation may be wise. Your insurer may cover additional living expenses.
Does insurance cover sewage backups?
Many homeowner policies require a sewer backup endorsement. Check yours.