# Mold after flood damage: the first 48 hours After a flood, the priority is to dry the home within 24 to 48 hours and remove what cannot be dried. If a flooded home was not dried in that window, assume mold growth. > Do this first: protect yourself with at least an N-95 respirator, goggles and non-latex gloves, and keep children and people with asthma or weakened immune systems out of the cleanup area. ## What to do in the first 48 hours 1. **Remove standing water and wet materials** Get standing water and soaked items out, and dry the area within 24 to 48 hours. Moisture control is the key to mold control. 2. **Open the home to airflow** Wait to re-enter until professionals say the home is safe. Then open doors and windows while you work, and leave as many open as is safe when you leave. Open interior doors, closets, kitchen cabinets and bathroom vanity doors, remove and stack drawers to dry, and open the attic access. 3. **Dry carpet and backing quickly** EPA says carpet and backing should be dried within 24 to 48 hours using water extraction, dehumidification and fans. 4. **Check before you run fans** If mold has already started to grow, do not use fans, because they may spread it. 5. **Throw away what cannot be dried** Anything wet with flood water that cannot be cleaned and dried completely within 24 to 48 hours should go. Porous materials such as carpet, ceiling tiles and insulation may have to be thrown away or replaced, because mold can grow into crevices and be difficult to remove completely. 6. **Call a professional for contaminated water** If the water may have carried sewage or chemicals, call a professional experienced in contaminated-water remediation. 7. **Run generators outside only** Use portable generators outside and at least 20 feet from buildings, never inside the house or garage, and never refuel a hot generator. ## Dry it or remove it Anything wet with flood water that cannot be cleaned and dried completely within 24 to 48 hours should go. Porous materials such as carpet, ceiling tiles and insulation may have to be thrown away or replaced. Carpet and backing should be dried within 24 to 48 hours with water extraction, dehumidification and fans. - Remove standing water and soaked items, then dry the area. - Do not use fans if mold has already started to grow. - Call a professional for water that may have carried sewage or chemicals. ## Numbers for the first two days - **24 to 48 hours** Dry flood-wet items; discard what cannot be cleaned and dried completely in this window - **20 feet** Minimum distance for a portable generator from buildings ## What to do and what not to do ### What to do - Assume mold if a flooded home was not dried within 24 to 48 hours. - Treat all mold the same; CDC says it is not necessary to determine the type. - Shower and change clothes after leaving a moldy site. ### What not to do - Do not run an HVAC system you know or suspect is contaminated with mold. - Do not refuel a hot generator, or run a portable generator inside the house or garage. ## Common questions ### How do I stop mold after a storm? Dry within 24 to 48 hours. Remove standing water, extract carpet and backing, and run dehumidification and fans until materials are dry. Open interior doors, closets and cabinets so air can reach every cavity, and pull drawers out to dry. If mold has already started growing, turn the fans off. Remember the generator rules: run portable generators outside, at least 20 feet from buildings, never in a house or garage, on a balcony, or near doors, vents or windows, and never refuel a hot generator. ### What do I do about mold after flooding? Treat floodwater as contaminated. CDC says flood water may carry sewage or chemicals, exposing occupants to viruses, bacteria, disease carriers and parasites as well as mold. If water or mold damage came from sewage or other contaminated water, call a professional experienced in contaminated-water remediation; OSHA requires PPE and containment for that work. Meanwhile, assume mold if the home could not be dried within 24 to 48 hours, and do not let children or people with asthma or weakened immune systems take part in cleanup. ### What do I have to throw away after a flood? Throw away anything wet with flood water that cannot be cleaned and dried completely within 24 to 48 hours. Porous materials are the usual casualties: carpet and pad, upholstered furniture, wet ceiling tiles, cellulose insulation and fiberglass insulation, and moldy drywall that is swollen or has open seams. Double-bag what you can, using 6-mil or thicker plastic, and wrap large pieces with heavy growth in polyethylene sealed with duct tape before carrying them out. ### How do I prevent mold after a flood? Dry within 24 to 48 hours: remove standing water and wet materials, open the house up for airflow, and throw away anything porous that cannot be cleaned and dried completely in that window. Do not use fans once mold is growing. If the water may have carried sewage or chemicals, treat it as contaminated and call a professional. Run portable generators outside, at least 20 feet from the building, and never inside a house or garage. ### Where do I run a generator during mold cleanup? Outside and away from the building. CDC says to use portable generators outside and at least 20 feet away from buildings, never inside the house or garage, and not on balconies or near doors, vents or windows. Never refuel a hot generator. The same post-flood guidance that covers mold cleanup covers the equipment keeping your fans and dehumidifiers running, and carbon monoxide is the reason the distance rules exist. ## Sources - CDC Guide to mold cleanup: https://www.cdc.gov/mold-health/communication-resources/guide-to-mold-cleanup.html - U.S. EPA Brief guide mold moisture and your home: https://www.epa.gov/mold/brief-guide-mold-moisture-and-your-home - U.S. EPA Mold remediation schools and commercial buildings guide chapter 4: https://www.epa.gov/mold/mold-remediation-schools-and-commercial-buildings-guide-chapter-4 - U.S. EPA Mold cleanup your home: https://www.epa.gov/mold/mold-cleanup-your-home - CDC: https://www.cdc.gov/mold-health/data-research/facts-stats/index.html https://southfloridamoldhelp.com/checklists/first-48-hours/