There are typically 2 types of inspection, Complete and Limited, which use up to five sampling techniques of mold and air testing available and used by inspectors. These sampling types include: Air samples, direct tapes and swabs, bulk samples, visual inspection and intrusive.
Visual Inspection
The visual part of the moisture and mold inspection includes a visual evaluation of the property, systems, HVAC, exterior, attic and basement areas. The purpose of the visual inspection is to help identify areas of concern for moisture sources and potential microbial growth identification. The visual inspection is typically the first step in the mold and moisture inspection, which includes environmental readings (humidity, moisture, temperature) and suggests where to conduct sampling.
Air Cassettes or Spore Traps
The Air Sampling cassettes, also call spore traps, are a sampling device designed for the rapid collection and analysis of a wide range of airborne aerosols. These include fungal spores, pollen, insect parts, skin cell fragments, fiber and inorganic particulates. They are also the most common method used for testing air quality.
The cassettes are attached to a specially lab=calibrated air pump with pumps air through the cassette for a predetermined amount of time. Air enters the cassette, the particles become impacted on the microscopic sampling substrate inside the cassette , and the air leaves through the exit orifice. The airflow and housing is designed in such a way that the particles are distributed and deposited equally on a special glass slide contained in the cassette housing. These particulates are then sent to a lab for evaluation by a licensed and certified technician for identification and calculation.
Direct Sampling – Tape lift and Swab
Tape lift and swab sampling are techniques used for direct examination. A direct exam allows for the immediate determination of the presence of fungal spores as well as what types of fungi are present. Direct examinations should only be used to sample visible mold growth in a contaminated area since most surfaces collect a mixture of fungal spores that re considered normally present in the environment.
Direct Bulk Sampling
Bulk testing, another form of Direct Examination, involves collecting or extracting pieces (typically 2″x2″) of material from the home or area of concern to test for mold. The materials are then taken to a laboratory where mold particles on the materials can then be examined under a microscope. Commonly, fabrics from furniture, drywall, wall coverings or carpets can be taken.