Mold wreaks havoc in hot, humid summer months

This has been a very difficult summer season for many schools and businesses in the northeast. The weather has been consistently hot and very humid and these hot, humid conditions can act as an incubator for mold in buildings where no humidity control is in place. There have been many news stories about schools delaying classes because of visible mold in classrooms that remained unoccupied during the summer months. Costly investigations into the extent of mold contamination and even more costly remediation/clean up activities can put an undo financial burden on any school or business.

Mold and moisture go hand and hand. Mold thrives indoors in hot, humid weather where humidity control such as air conditioning is not in place or is not used in a way that effectively lowers the relative humidity in the space. Air conditioners remove moisture from the air and fungal growth is less likely to occur in areas where the relative humidity is less than 60%, however, in many buildings, especially schools, that operate at less than capacity during the summer months, warm, humid air conditions provide a perfect environment for fungal growth.

The primary key to avoiding mold growth in your building is humidity control. It is imperative that relative humidity be kept below 60%.

A second key factor in controlling mold growth is the identification and regular inspection of areas that may be susceptible to fungal growth. These inspections provide the building owner/property manager a real time look at what is occurring in their building.

Although there are no federally enacted regulations related to the indoor air quality industry, several standards exist to assist industry professionals. PROAC Corporation has adopted the American Standard Testing Materials (ASTM) standard D 7338-14, “Standard Guide for Assessment of Fungal Growth in Buildings” as our reference for completing indoor air quality investigations.  ASTM is an international standards organization that develops and publishes voluntary, consensus technical standards for a wide range of products and services.  Many ASTM standards have been adopted, by incorporation, into federal, state and municipal regulations.

This guideline presents a framework for locating and evaluating suspect fungal growth in buildings. Components of a basic assessment strategy include 1) defining a scope of work, 2) collecting background information related to the building, 3) formulation of a hypothesis, 4) an on site survey for fungi, moisture dynamics and HVAC operation and 5) documentation and reporting.

Additionally, both the National Air Duct Cleaners Association (NADCA) in their document “Assessment, Cleaning and Restoration 2015” standard ACR 2015 and the American      Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE) in their “Standard Practice for Inspection and Maintenance of Commercial Building HVAC systems” standard 180-2016 suggest a proactive approach to HVAC inspections and maintenance as a means of lowering operating/maintenance costs and insuring that these systems operate in a manner that supplies good, conditioned air to the breathing zone.

PROAC Corporation is a longstanding member of both NADCA and ASHRAE. As our name indicates, we are proponents of proactive maintenance. Proactive surveys help to prevent fungal problems from starting in the first place. We offer an IAQ/HVAC survey program designed to identify conditions that may aid in fungal growth. We offer recommended actions designed to rectify the undesirable conditions. Our program includes completing an initial survey to establish background information including readings of Temperature, Relative Humidity (RH), Carbon Dioxide (C02), Carbon Monoxide (CO), Total Volatile Organic Compounds (TVOC) and Particle Counts. The survey also includes a visual inspection of all areas occupied areas. A visual inspection of the Air Handler Units (AHU’s) is also included as an intergral part of these surveys. Reports with photo documentation are provided.

The surveys are completed by ACAC accredited Certified Indoor Environmental Consultants (CIEC) and NADCA accredited Certified Ventilation Inspectors (CVI).

For more information on this valuable service, Please visit our webpage at or contact us directly at (717)933-9475 for all your indoor air quality needs.