Formula or decision rule
affected floor area = sum of safe-to-measure room zones; material inventory = count or area by wet material and contamination class- Time since wetting is recorded as observed elapsed time, not used to predict safety.
- Porous and non-porous materials stay separate in the inventory.
- Safety-screen failures override area and schedule calculations.
Flood triage worksheet
| Check | Record | Stop/escalate when |
|---|---|---|
| Electrical supply | service status and standing water | shock risk or uncertain isolation |
| Water source | clean, sewage, chemical, unknown | contaminated or unknown |
| Structure | movement, sagging, damage | stability uncertain |
| Drying | wet materials and elapsed time | capacity or access is inadequate |
Work through the project
Establish safe entry
Resolve electrical, structural, contamination, gas, and carbon-monoxide risks before measuring or removing material.
Inventory by room and material
Record affected area, depth or extent, porous contents, wall assemblies, flooring, and HVAC involvement.
Dry and reassess
Follow the jurisdiction guide, keep combustion equipment outdoors, and reassess for mould or concealed moisture.
Safety and scope
- Never run generators, pressure washers, or other fuel-burning equipment indoors or near openings.
- Standing water near electrical sources, sewage, chemicals, structural damage, or extensive mould requires qualified response.
Sources and scope
Source links reviewed July 16, 2026. A review date is not the document's publication date.
- U.S. Environmental Protection Agency: Flood Cleanup to Protect Indoor Air and Your HealthUnited States · government guide
Electrical, structural, sewage, chemical, and extensive mold hazards require qualified help.
- Health Canada: Flood cleanup — Keep in mind indoor air qualityCanada · government guide
The guide says bleach is not necessary for mould cleanup and combustion equipment must remain outdoors.
- U.S. Environmental Protection Agency: Mold Cleanup in Your HomeUnited States · government guide
EPA uses an area of about 10 square feet as a decision point while also identifying other reasons to seek professional help.
- Health Canada: Addressing moisture and mould in your homeCanada · government guide
The moisture source must be corrected; large or recurring growth calls for professional assessment.