What happens to indoor spore levels in buildings with poor ventilation?

In buildings with poor ventilation, indoor spore levels often become higher than outdoor levels. This occurs for several reasons. Firstly, inadequate air exchange means that spores generated indoors, whether from mold growth or other organic sources, are not effectively removed.

Additionally, outdoor spores can enter the building through windows and doors, but if those openings are few and inadequate, the influx is insufficient to balance out the accumulation of spores indoors. The stagnant air condition allows spores to settle and collect in dust and surfaces, further contributing to the concentration of indoor mold spores.

Humidity levels often rise in poorly ventilated spaces, creating an ideal environment for mold growth. This can lead to the proliferation of mold, which releases more spores into the air, exacerbating the problem and increasing indoor spore levels. Thus, a combination of poor air circulation, accumulated spores, and potential mold growth results in indoor spore concentrations that can surpass those found outdoors.