June 3, 2011

Some areas of Nebraska are experiencing water entry into homes from flooding, and residents should take special precautions.

Flood waters may contain fecal matter from sewage systems, agricultural and industrial waste, and septic tanks. Wear rubber gloves, protective clothing and a tight-fitting facemask, such as an N-95 or N-100 air filter mask, when working around mold and contaminated flooded areas. Persons with medical problems such as suppressed immune system or breathing problems, young children and the elderly should not be involved in the cleaning, said Shirley Niemeyer, University of Nebraska-Lincoln Extension housing and environment specialist.

If you have open cuts or sores exposed to the floodwater, keep them as clean as possible by washing them with soap and disinfectant and boiled water. Apply antibiotic ointment to reduce the risk of infection. Do not allow children to play in floodwater and the area contaminated or with toys that are contaminated by floodwater.

Basic hygiene is very important during flooding. Always wash your hands with soap and clean water before eating, and after toilet use, cleanup activities, or handling items contaminated by floodwater or sewage.

Removing some flood contaminated materials and household goods and thoroughly cleaning or drying out others are essential steps to combat mold, Niemeyer said.

Floodwaters compromise household fixtures in different ways. Porous materials are nearly impossible to clean. Flood soaked carpets, carpet pads, linoleum, fabric covered furniture, mattresses, drywall or wall board, wet insulation and ceiling tiles should be discarded. For heirloom rugs and furniture, contact a professional cleaner.

Mold problems often continue to appear five to six weeks after a flood has occurred, but steps can be taken to combat mold growth and its potential to cause serious health problems as well as structural damage to homes. Warm humid weather speeds up mold growth.

Appliances such as refrigerators, freezers, stoves, dishwashers, hot water heaters, washing machines and driers contain insulation that may harbor mold spores without visible evidence and should be discarded or inspected by a qualified professional appliance repair person, Niemeyer said.

Heating and air conditioning filters should be changed and if contaminated, the ductwork cleaned by a professional. Have a heating and cooling professional inspect air conditioners and heating systems to determine the damage.

Damaged wallboard should be discarded. Water can rise in the material higher than the visible water line. The best practice is to remove the wallboard at least two feet or more above the water line. Leave the wall cavity open for several weeks to months to allow the components to dry. A moisture meter, available in some plumbing, heating and air conditioning businesses or through the Internet, can be used to determine when the materials are dry. Even though the wood or other materials may feel dry, the moisture level may still be too high to close up the cavity. To prevent mold growing within the wall or floor cavity, wait until the wood and area is completely dry.

It may be necessary to open up the floor cavities to prevent buckling of the floor, to clean, and to allow drying. Remove some of the floor covering and decking to determine the extent of the damage. When possible, inspect from the underside of the floor.  Hard, non-porous surfaces, including glass, steel, most ceramic, metal and hard plastic, can usually be cleaned. A water and detergent can be used to wash down surfaces. Because floodwaters carry contaminants, bacteria, viruses, etc., a disinfectant should be used.

Follow directions on containers and take particular note of warnings. Mixing chlorine and ammonia creates an extremely dangerous poisonous gas. Wear rubber gloves, protective clothing and a tight-fitting face mask when working around mold and when working with biocides.

More information is available at http://www.extension.org/floods.

Dan Moser
IANR News