Health Concerns After a Flood

Floods September 30, 2014 Print Friendly and PDF

Occupant Health Concerns

Should I be concerned about living in a moldy home?

Mold in the air is associated with a number of health problems.

  • For many people these are minor, and include congestion, irritation of the eyes, nose and throat, and coughing. Rashes can also develop.
  • Some people are more sensitive or allergic to mold. They are affected by exposures that don’t affect most other people.
  • For people with asthma, mold can serve as a trigger for asthma attacks.
  • In heavy or prolonged exposure, mold can cause serious and sometimes long-lasting health problems.
  • Some conditions make people especially susceptible to mold. These conditions include anything that weakens the immune system, such as HIV/AIDS, certain medications (for example, those used in transplant surgery), and some illnesses. The very young and the elderly may also be at higher risk.
  • Exposure to high levels of mold, as in occupational settings or in mold infested flooded buildings can trigger more serious health effects. These can include lung infections and a long-term disease resembling recurring pneumonia.
  • Mold, bacteria, and viruses thrive in damp environments, as do insect pests and vermin.

Can I just kill the mold with bleach to make my home safe?

  • No.
  • While chlorine bleach and other biocides may kill the mold, they do not inactivate harmful allergens, irritants, and other mold materials that may impact health.

What are safe levels of mold?

  • At this time there are no government established exposure levels for mold. This is largely due to differing individual responses to mold: what makes one person sick has no effect on another. Thus, it is impossible to say some level of mold exposure is safe or that a particular level will make people sick. However, it is not healthy to live or work in a mold infested building.
  • People with allergies or asthma, those with impaired immune systems, the very young, and the elderly may be especially sensitive to mold.

Worker Heath Concerns

Are there special health risks for those cleaning up moldy houses?

  • Yes, unless the cleanup is done safely. This means proper protection for those doing the work. Personal protection for workers can range from a minimum of eye protection, gloves and a well fitting, good quality (N95) mask to body suit and a full-face, powered air purifying respirator. For mold clean-up tasks involving more than 10 to 20 square feet of mold, maximum worker protection is needed. A health department official, industrial hygienist, or other qualified individual should be consulted concerning protective gear, respirator fit-testing, and other precautions.
  • If only part of the house is flooded, the work area should be sealed off from the rest of the house and occupants kept out of the area.

NOTE Any disturbance of dried mold colonies will release large amounts of spores and other mold debris into the air creating a health hazard.

Read more about mold on the U.S. Environmental Protection Agency website.

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