Water Damage Categories 1, 2, and 3 — IICRC S500 Standard

The IICRC S500 Standard for Professional Water Damage Restoration defines three contamination categories. Each requires different safety protocols and restoration procedures in Sonoma County homes and businesses.

Category 1 — Clean Water

Category 1 water originates from sanitary sources: broken supply lines, appliance malfunctions, or rainwater. It poses minimal health risk if addressed within 24–48 hours. Materials affected by Category 1 water can often be dried in place.

Category 2 — Gray Water

Category 2 water contains significant contamination from washing machine overflow, dishwasher discharge, or toilet overflow with urine only. Affected porous materials typically require removal and replacement.

Category 3 — Black Water

Category 3 is highly contaminated water containing sewage, rising floodwater, or stagnant Category 1/2 water. All porous materials in contact with Category 3 must be removed. Full personal protective equipment (PPE) is required. NBRA member companies are trained for safe Category 3 remediation throughout Sonoma County.