Editing Mold (section)

==Growth in buildings and homes==
{{Main|Indoor mold|Indoor air quality}}
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[[File:Moldy Housecorner both Sides.jpg|thumb|upright=1.35|Moldy housecorner from outside and inside]]
Mold growth in buildings generally occurs as fungi colonize porous building materials, such as wood.<ref>{{cite web |last1=Fairey |first1=Philip |last2=Chandra |first2=Subrato |last3=Moyer |first3=Neil |title=Mold Growth |url=http://www.fsec.ucf.edu/en/consumer/buildings/basics/moldgrowth.htm |website=Florida Solar Energy Center |publisher=University of Central Florida |access-date=19 August 2019 |archive-date=27 August 2019 |archive-url=https://web.archive.org/web/20190827183935/http://www.fsec.ucf.edu/en/consumer/buildings/basics/moldgrowth.htm |url-status=live }}</ref> Many building products commonly incorporate paper, wood products, or solid wood members, such as paper-covered drywall, wood cabinets, and insulation. Interior mold colonization can lead to a variety of health problems as microscopic airborne reproductive spores, analogous to tree pollen, are inhaled by building occupants. High quantities of indoor airborne spores as compared to exterior conditions are strongly suggestive of indoor mold growth.<ref>IICRC S500 Standard and Reference Guide for Professional Water Damage Restoration</ref> Determination of airborne spore counts is accomplished by way of an air sample, in which a specialized pump with a known flow rate is operated for a known period of time. To account for background levels, air samples should be drawn from the affected area, a control area, and the exterior.

The air sampler pump draws in air and deposits microscopic airborne particles on a culture medium. The medium is cultured in a laboratory and the fungal genus and species are determined by visual microscopic observation. Laboratory results also quantify fungal growth by way of a spore count for comparison among samples. The pump operation time is recorded and when multiplied by pump flow rate results in a specific volume of air obtained. Although a small volume of air is actually analyzed, common laboratory reports extrapolate the spore count data to estimate spores that would be present in a cubic meter of air.<ref>{{Cite web|url=http://prestige-em.com/tech/AirborneFungalSporesByCulture.htm|title=Prestige EnviroMicrobiology, Inc.|website=prestige-em.com|language=en|access-date=2018-03-26|archive-date=2017-03-01|archive-url=https://web.archive.org/web/20170301233659/http://prestige-em.com/tech/AirborneFungalSporesByCulture.htm|url-status=live}}</ref>

Mold spores are drawn to specific environments, making it easier for them to grow. These spores will usually only turn into a full-blown outbreak if certain conditions are met.<ref>{{Cite web|url=https://www.epa.gov/mold/brief-guide-mold-moisture-and-your-home|title=A Brief Guide to Mold, Moisture and Your Home|website=EPA|date=13 August 2014 }}</ref> Various practices can be followed to mitigate mold issues in buildings, the most important of which is to reduce moisture levels that can facilitate mold growth.<ref name=niosh /> Air filtration reduces the number of spores available for germination, especially when a High Efficiency Particulate Air (HEPA) filter is used. A properly functioning AC unit also reduces the relative humidity in rooms.<ref>{{Cite web|url=https://www.aiha.org/publications-and-resources/TopicsofInterest/Hazards/Pages/Facts-About-Mold.aspx|title=Facts About Mold|website=www.aiha.org|language=en-us|access-date=2018-03-26}}</ref> The United States Environmental Protection Agency (EPA) currently recommends that relative humidity be maintained below 60%, ideally between 30% and 50%, to inhibit mold growth.<ref>{{Cite web|url=https://www.epa.gov/mold/brief-guide-mold-moisture-and-your-home|archive-date=January 6, 2020|archive-url=https://web.archive.org/web/20200106221435/https://www.epa.gov/mold/brief-guide-mold-moisture-and-your-home|title=A Brief Guide to Mold, Moisture and Your Home|website=US EPA|date=13 August 2014 }} Click on "Moisture and Mold Prevention and Control Tips".</ref>

Eliminating the moisture source is the first step at fungal remediation. Removal of affected materials may also be necessary for remediation, if materials are easily replaceable and not part of the load-bearing structure. Professional drying of concealed wall cavities and enclosed spaces such as cabinet toekick spaces may be required. Post-remediation verification of moisture content and fungal growth is required for successful remediation. Many contractors perform post-remediation verification themselves, but property owners may benefit from independent verification. Left untreated, mold can potentially cause serious cosmetic and structural damage to a property.<ref>{{Cite web|url=https://www.gtamoldremoval.com/mississauga.html|title=What is Mold?|website=gtamoldremoval.com|date=14 September 2024 }}</ref>