You ventilate to remove the extra indoor produced humidity and to exchange
it for new air with lower humidity and lower levels of carbon dioxide.
By comparing the amount of damp in the in- and outdoor air, you can
see if it is normal.
If the indoor air is abnormally damp you need to look for the source of the damp, which can be due to a construction fault or a leaking plumbing, alternatively not good enough ventilation.
Fungus is detected by bad smell, discolouring of surfaces, sagging floors and rich occurrence of insects (silverfish, wood louse, spiders, mites and others). To prove hidden occurrence of fungus, a fungal analysis is necessary. Remaining smell after water damages is prevalent. Therefore a smell sanitizing is often done. You get rid of much of the smell by airing and increased ventilation. However, the ozone aggregates an effective utility.
Ozone is a toxic oxygen compound that reacts with organic compounds. Odorants in the air you breathe is oxidized –annihilated.
High humidity is a prerequisite for the Real House Fungus to establish itself. Damp damages can arise as a result of many causes, e.g. unventilated crawl spaces, wrongly insulated houses or as a result of a water damage that have not been taken care of in the right way.