Last month I touched on the topic of mold within the built healthcare environment. But what about mold in the harder to see-or-reach spaces of the hospital, such as deep in the recesses of the buildings HVAC system? Mold requires 4 basic things to proliferate, including food, oxygen, temperatures between 40-100 degrees, and moisture. All of these ingredients are available within HVAC air-handling systems, particularly near cooling coils which trap mold spores (entering the building through ventilation air) and dirt (food source), then create condensation (moisture) in conditioning the supply air to approximately 52°F (temperature). In fact, the air-handling system is the textbook breeding ground for biological contaminants, which can then be distributed in the ductwork which conveys air all throughout the facility.
The tragedy at Seattle Childress Hospital which resulted in 14 infections and 6 deaths (class action lawsuit pending) has been identified as resulting from small amounts of Aspergillus mold found in and near operating rooms, and it’s claimed to have been caused by the hospitals HVAC air-handling system. Aspergillus is particularly concerning as its readily aerosolized, where upon exposure, inhalation is more likely. In addition, some species can produce mycotoxins which can grow inside the lungs of immunocompromised individuals, possibly resulting in illness or even death. Part 3 on the important topic of eliminating mold in healthcare environments will discuss some of the more effective methods to remediate the issue of mold growth in HVAC systems.