Mold is detectable by smell and signs of water damage on walls or ceiling, and can grow in places invisible to the human eye. It may be found behind wallpaper or paneling, on the inside of ceiling tiles, the back of drywall, or the underside of carpets or carpet padding. Piping in walls may also be a source of mold, since they may leak (causing moisture and condensation).
Spores need three things to grow into mold: nutrients – cellulose (the cell wall of green plants) is a common food for indoor spores; moisture – To begin the decaying process caused by mold; time -mold growth begins from 24 hours to 10 days after the provision of growing conditions. Mold colonies can grow inside buildings, and the chief hazard is the inhalation of mycotoxins. After a flood or major leak, mycotoxin levels are higher even after a building has dried out.