NC STATE Home Page NC STATE UNIVERSITY - Environmental Health and Safety 2620 Wolf Village Way Cmpus Box 8007, Raleigh NC 27695  Phone 919.515.7915 FAX 919.515.6307 NC STATE Home Page

Flooded Area Safety & Sanitation

When flooding of an area has occurred, either from internal sources, heavy rains or sewer backup, important steps must be taken to assure the health and safety of individuals involved.  If the department is not able to perform the cleanup operation in a short period of time or needs outside assistance, University Housekeeping (515-9920) or Facilities Operations Work Center (515-2991) after hours, should be contacted for personnel and equipment.  For severe flooding events, particularly when originating from overhead sources, call 911 to obtain emergency assistance.  Severe flooding may result in electrical or fire hazards.  In some cases, power to the building may need to be shut down.  Some flooding events may be outside the scope of University personnel to resolve quickly and therefore, an outside restoration contractor will need to be brought in.  This can be accomplished by contacting the Facilities Operations Work Center.  Facilities Operations maintains a list of restoration contractors.
It must be assumed during cleanup operations of external water sources and sewage backup that all surfaces have been contaminated with disease causing microorganisms. This important assumption must be considered in decisions involving personal safety of cleanup as well as what items may be salvaged and what must be discarded.
Standing water is a breeding ground for microorganism, which can become airborne and inhaled. Flooding from external sources and sewage backup produces growth of microorganisms that can cause allergic reactions in sensitive individuals. For health reason, all standing water needs to be removed as quickly as possible.  See link for information concerning mold and biologicals affecting indoor air quality:
Indoor Air Quality Program


  1. Only individuals necessary for cleanup should be in affected area. Persons with respiratory health problems should NOT perform cleanup of contaminated water.
  2. Gloves must be worn at all times. Double gloving is recommended. Rubber or other types of waterproof boots should be used when indicated. Eye protection, including goggles or minimally safety glasses with side shields, needs to be worn where rigorous splashing of contaminated water or disinfectant may occur.
  3. Provide good ventilation when using a bleach or sanitizing solution.
  4. Cover all cuts or sores with appropriate protection.
  5. Eating, smoking or drinking during clean up is prohibited.


  1. Occupants should be evacuated from affected area if the water source is contaminated so that spreading of contaminants does not occur.  People should also be restricted from entering areas where standing water is present to prevent falls and electrical shocks.
  2. Be certain there are no electrical shock hazards. Wear rubber boots in wet area until it is clear no electrical hazards exist. Contact Facilities Operations if assistance is needed.
  3. Turn off main switches and unplug appliances, computers, and other electronic equipment in wet areas.
  4. Keep all appliances, electronics, and other electrical equipment turned off which have become wet until they have been thoroughly dried and checked for proper operation. Fans can be used to move air across de-energized electrical equipment, especially electronics to facilitate drying and only if there are no ambient electrical shock hazards existing.


External and Sewage Backup Water
Bacteria, viruses, mold and fungi must be killed in the clean up process. An example of a sanitizing agent is bleach; however, other approved disinfectant solutions may be used. For adequate disinfection the bleach solution must be one cup of bleach to one gallon of water. 
Time is an important consideration in clean up. Organisms to be killed will not become airborne as long as they remain wet. Once dried, organisms can spread by dust particles. Consequently, it is important to bring the sanitizing solution in contact with contaminated surfaces as soon as possible after rinsing off heavy soil.

  1. Damp wipe solution on the wall several inches up from the highest level reached by the floodwaters and over the entire floor. Make sure all affected surfaces have been contacted with the solution. Full strength bleach may be needed in areas of heavy contamination. In this situation make sure there is adequate ventilation and PPE.
  2. If the water has reached more than a few inches up the walls, hollow walls will need to be opened. Check drywall with a moisture meter and cut off the portion of the drywall that has become wet. Saturate the remaining studs with the bleach solution.
  3. Dry all surfaces as much as possible. Keep in mind the bleach solution needs at least 15 minutes to kill organisms. Do not use a fan until area has been cleaned and disinfected.
  4. Any carpet that has been contaminated with sewage backup must be discarded under controlled conditions.   Facilities Operations, Repair and Renovation Office (515-2991) should be contacted for all affected structural materials such as carpeting and wall board, requiring repair and renovation.


Water from roof leaks, steam leaks, potable water and uncontaminated ground water

  1. Carpet that has become wet from roof leaks, steam leaks, potable water leaks and uncontaminated ground water can be treated as follows:
    1. Carpet wet LESS THAN 48 hours
      1. remove all materials from the carpet
      2. extract as much water as possible from the carpet using wet vacuums, contact Facilities Operations work center for water extraction equipment.  Only powered extractor equipment supplied with a ground fault extension cord may be used.
      3. shampoo the carpet with a dilute disinfectant
      4. rinse and extract the carpet with clean water to remove detergent residues
      5. dry the carpet within 12-24 hours of treatment. After work is finished increase the room temperature and use commercial dehumidifier, floor fan or exhaust fan to aid in drying the carpet.
    2. Carpet wet MORE THAN 48 hours
      1. Disposal of water damaged carpets is the best option.  Contact Facilities Operations Repair and Renovation Office (515-2991) to remove carpet.
  1. Porous walls, wall structures and ceiling tiles that have remained wet from roof leaks, steam leaks, potable water leaks and uncontaminated ground water for over  72 hours will need to be replaced.  Contact Facilities Operations Repair and Renovation Office for this work.


  1. Insurance and Risk Management (IRM) (515-6124) should be contacted to provide consultation and assistance on property damage mitigation. IRM can also provide assistance on damage assessment, and if your department has opted to purchase the appropriate property insurance coverage, can assist with your property insurance claim. There also may be water damage events where non- University parties may be held liable for water damage to University property and IRM can provide consulting assistance on any such potential property damage liability recovery claim.
  2. Facilities Operations Repair and Renovation Office (515-2991) should be contacted for assistance in determining if structural materials have properly dried and in developing a list of structural materials to be replaced.
  3. Health concerns arising from flooding events with biologically or chemically  contaminated water, e.g. sewage backup, should be directed to EHSC (513-0647).
  4. Department’s Building Liaison will follow up with Facilities Operations Repair and Renovation Office and EHSC’s recommendations for relocating personnel and implementing changes in work schedules due to structural repair and renovation work. 


  • Keep computer hard drives and other items off the floor. Elevate items at least 6 inches.
  • Consider replacing carpet with floor tiles.
  • University Housekeeping will provide advice in securing outside help but will not assist in cleaning electronic equipment, such as computers and hard drives exposed to water in flooding events.