Indoor mold
When the temperature, moisture, and available nutrient conditions are correct, the spores can form into new mold colonies where they are deposited.
In large amounts they can lead to mold health issues to humans, potentially causing allergic reactions and respiratory diseases.
[3] More than half of adult workers in moldy/humid buildings suffer from nasal or sinus symptoms due to mold exposure.
[6] Some mold produce mycotoxins, chemical components of their cell walls, that can pose serious health risks to humans and animals.
[7][dubious – discuss] Exposure to high levels of mycotoxins can lead to neurological disorders and death[citation needed].
Flooding, leaky roofs, poor building maintenance, or indoor plumbing problems can lead to interior mold growth.
[9] Water vapor commonly condenses on surfaces cooler than the moisture-laden air, enabling mold to flourish.
[citation needed] This moisture vapor passes through walls and ceilings, typically condensing during the winter in climates with a long heating season.
Mold is detectable by smell and signs of water damage on walls or ceiling and can grow in places invisible to the human eye.
[citation needed] Food sources for mold in buildings include cellulose-based materials such as wood, cardboard and the paper facing on drywall and organic matter such as soap, textiles, and dust containing skin cells.
Visible mold colonies may form where ventilation is poorest and on perimeter walls (because they are nearest the dew point).
Mold problems occur in airtight homes more frequently in the warmer months (when humidity is high inside the house, and moisture is trapped), and occur in drafty homes more frequently in the colder months (when warm air escapes from the living area and condenses).
Heating, ventilation, and air conditioning (HVAC) systems can produce all three requirements for mold growth.
The high rate of dusty air movement through an HVAC system may furnish ample food for mold.
Mold growth can be inhibited by keeping surfaces at conditions that are further from condensation, with relative humidity levels below 75%.
[13] Even something as simple as drying clothes indoors on radiators can increase the risk of mold growth, if the humidity produced is not able to escape the building via ventilation.
[14] Residential mold may be prevented and controlled by cleaning and repairing rain gutters, to prevent moisture seepage into the home; keeping air-conditioning drip pans clean and drainage lines clear; monitoring indoor humidity; drying areas of moisture or condensation and removing their sources; ensuring that there is adequate ventilation by installing an exhaust fan in your bathroom; treating exposed structural wood or wood framing with a fungicidal encapsulation coating after pre-cleaning (particularly homes with a crawl space, unfinished basement, or a poorly-ventilated attic).
The area should be surveyed for odors indicating mold or bacterial growth, moisture sources, such as stagnant water or leaking pipes, and water-damaged building materials.
[8] The United States Environmental Protection Agency (EPA) does not generally recommend sampling unless an occupant of the space has symptoms.
Dust from surfaces such as floors, beds, or furniture is often collected to assess health effects from exposure in epidemiology studies.
The Environmental Relative Moldiness Index (ERMI) is a numerical that can be used in epidemiological studies to assess mold burdens of houses in the United States.
The ERMI consists of a list of 36 fungal species commonly associated with damp houses that can be measured using qPCR.
If not attended to, the growth can spread through the property contributing to adverse health problems and causing secondary damage to the structure and its contents.
[citation needed] The goals of remediation are to remove (or clean) contaminated materials, preventing fungi (and fungi-contaminated dust) from entering an occupied (or non-contaminated) area while protecting workers performing the abatement.
[26] Contamination levels have been enumerated as I, II, III, and IV:[citation needed] After remediation, the premises should be reevaluated to ensure success.
