Indoor air quality is complex.  Testing for a substance is not complicated.   Instruments come with instruction manuals and videos on how to use.  Laboratories provide sampling methodologies.  What is more difficult is to determine what to test for, where to test, and what data would the outcomes provide.  In order to make a determination, a basic understanding of the psychrometrics and science of the particular building or home must be considered.

Psychrometrics is the science of physical and thermodynamic properties of gas-vapor mixtures.   In the indoor environment is the science of the specific indoor gas-vapor mixture, or in other words, indoor air, which includes water vapor.  Temperature, pressure, air flow all impact gases and thus impacts the indoor air.    

Building science is a field of knowledge that focuses on the analysis of the actual phenomena that impacts buildings.  For indoor air quality purposes, this includes understanding the design of the building, the HVAC systems, and occupant usage in addition to the psychrometric data.  

There are certainly situations in which there is a known moisture leak and visible mold.    The investigation of a situation is not complicated.   However, professional remediation of the problem does include understanding of the psychrometric and some components of the building systems.  HVAC systems should be turned off and sealed to prevent contamination of the workspace.   Turning off an HVAC system has implications to the psychrometric properties of the building and could cause other issues elsewhere.       

Mold spores are ubiquitous.  In other words, mold spores are found everywhere.   Mold spores enter homes and buildings when opening doors and other regular activities.    Mold does not grow without moisture.   Understanding moisture in a building is often a lot more than just finding a leak or taking a quick relative humidity measurement.  Finding a leak can be challenging when concealed, but understating water vapor or the moisture in the air is much more complex.  The relative humidity is only an indicator of the moisture in the air, at the current temperature. When temperature changes, so does the relative humidity.  This does not necessarily indicate that the amount of moisture has changed.  Water vapor that condenses and water that evaporates may be difficult to see happen, thus looking for evidence of may be important to determine elevated moisture in an environment.

Building science and psychrometrics are fundamental to understanding indoor air quality.   Indoor Air Programs understands the complexities that can cause and/or impact indoor air quality.

Simple issues do not require complexity.   However, failing to recognize a more complex situation typically wastes resources.