The first step in an assessment is to determine if mold is present. Once an assessment is comleted with a non-intrusive analysis, further investigation, estimates and information can be provided. If mold is growing and visible, this helps determines the level of removal that is necessary. If mold is actively growing and is visibly confirmed, sampling for specific species of mold is unnecessary.
These methods, considered non-intrusive, only detect visible and odor-causing molds. Sometimes more intrusive methods are needed to assess the level of mold contamination. This would include moving furniture, lifting and/or removing carpets, checking behind wallpaper or paneling, checking in ventilation duct work, opening and exposing wall cavities, etc.
Careful detailed visual inspection and recognition of moldy odors should be used to find problems needing correction. Efforts should focus on areas where there are signs of liquid moisture or water vapor (humidity), or where moisture problems are suspected. The investigation goals should be to find indoor mold growth to determine how to correct the moisture problem and remove contamination safely and effectively.
The basic goals of any mold investigation are always twofold: 1) find the locations of mold growth, and 2) decide the sources of the moisture. If these can be answered by simpler or more cost-effective methods, mold testing is probably not a wise use of resources.