Occupational Safety and Health Administration OSHA

FactSheet Logo Fact Sheet

General Decontamination

During a flooding event, there is an increased danger of contracting bacterial, viral and protozoal diseases. Floodwaters can be contaminated with sewage and decaying animal and human remains. Therefore, disinfection of contaminated hands, clothing, tools/equipment, and surfaces in work areas is critical in disease prevention. Household bleach solutions of various strengths can be used for this purpose.

Hand Decontamination

  • Wash hands completely with soap and water.
  • Rub your hands together for at least 10 seconds (with soap if available). Wash all surfaces well, including wrists, palms, backs of hands, fingers, and under the fingernails.
  • Clean the dirt from under your fingernails.
  • Rinse the soap from your hands.
  • Dry your hands completely with a clean towel if possible (this helps remove the germs).
  • However, if towels are not available it is okay to air dry your hands.
  • Pat your skin rather than rubbing it to avoid chapping and cracking.
  • If you use a disposable towel, discard it in the trash.

Clothing, Tool and Equipment Decontamination

Contaminated clothing, tools and equipment should also be cleaned. It is preferable that soap and clean water be used when available. If only contaminated water is available use the following:

  • 1/4 cup bleach.
  • 1 gallon of water.
  • Immerse objects in the solution for 10 minutes; if clothing, gently swirl every few minutes.
  • If clothing, wring out as much moisture as possible.
  • If tools or equipment, allow the object to drain and then transfer it directly to the bleach solution used for hand cleaning.
  • Re-immerse the clothing in the household bleach solution used for hand cleaning for 10 minutes with periodic gentle swirling of the clothing.
  • If clothing, wring out as much moisture as possible.
  • Allow clothes to thoroughly dry before using again.

Severe Surface Decontamination

Surfaces that are heavily contaminated with mold, feces, or body tissues should be disinfected using the following household bleach solution:

  • 1 1/2 cups bleach.
  • 1 gallon of water.
  • Place the solution in a spray dispenser.
  • Thoroughly douse surfaces that have heavy deposits of contaminants and allow to stand for 3 minutes.
  • Wipe the contaminants from the surface with a paper towel.
  • Discard the towel.
  • Douse the surface again but use the bleach solution that is used for hand washing and wipe off the residual contamination with a paper towel.
  • Discard the towel and allow surface to dry.

Important Considerations

  • For greatest effectiveness, prepare bleach solutions fresh daily, preferably just prior to use.
  • Allow all bleach solutions to stand for at least 30 minutes before using.
  • Do not immerse electrical or battery operated tools/equipment in bleach solutions; wipe the outside of these objects with a disposable rag soaked with the solution and allow it to dry.
  • Use gloves and eye protection when cleaning clothes, tools/equipment, and surfaces. Use respirator protection (an N-95 respirator is recommended) when mold is present.
  • All containers should be labeled "Bleach-disinfected water: DO NOT DRINK."
  • CAUTION: Never mix bleach with products containing ammonia.

This is one in a series of informational fact sheets highlighting OSHA programs, policies or standards. It does not impose any new compliance requirements. For a comprehensive list of compliance requirements of OSHA standards or regulations, refer to Title 29 of the Code of Federal Regulations. This information will be made available to sensory impaired individuals upon request. The voice phone is (202) 693-1999; teletypewriter (TTY) number: (877) 889-5627.


For more complete information:

footnote imageOccupational
Safety and Health

U.S. Department of Labor
(800) 321-OSHA


DSG 9/2005

Thank You for Visiting Our Website

You are exiting the Department of Labor's Web server.

The Department of Labor does not endorse, takes no responsibility for, and exercises no control over the linked organization or its views, or contents, nor does it vouch for the accuracy or accessibility of the information contained on the destination server. The Department of Labor also cannot authorize the use of copyrighted materials contained in linked Web sites. Users must request such authorization from the sponsor of the linked Web site. Thank you for visiting our site. Please click the button below to continue.