Harry Neill, CIH, Industrial Hygienist and Mold Expert
Case Description/Summary: Over a period of several years, in patient rooms, an acute care healthcare facility experienced condensation forming on metal window frames, water dripping from soffits, and water-damaged gypsum wallboard on the exterior walls during the winter months. Repeated cosmetic attempts were made to repair the gypsum wallboard by patching and painting. The nursing staff raised concerns when visible mold growth was starting to be observed on the gypsum wallboard walls and soffits in patient rooms.
Expert Analysis: A team approach was employed which included forensic architects and structural engineers, mechanical engineers, and certified industrial hygienists. Water testing of windows and facade components, as well as destructive testing, were completed in select patient rooms. Upon removal of building finishes, frost was observed on the pre-cast concrete facade. Additionally, visible mold growth was observed on the backside of the gypsum wallboard soffits, window jams, and the pre-cast concrete facade. Other moisture sources were identified which included plumbing and toilet leaks. The mechanical engineers evaluated the air-handling unit operating characteristics and room conditions to help address the condensation concerns.
Conclusion/Results: The remediation plan included HVAC system modifications, removal and replacement of windows, removal and replacement of all exterior building finishes, cleaning and treating of moldy pre-cast concrete, and re-insulation with spray foam insulation on the pre-cast. All work was conducted under the Infection Control Risk Assessment Matrix of Precautions for Construction and Renovation and, in this case, included full hard barrier containments, negative pressurization with an ante room air lock, and dust control methods. The work was phased in vertical sections of the building to maintain healthcare facility operations as the repairs were made.
Key Factors: Independent visual inspections and sampling were conducted after each phase to ensure that the moldy conditions were effectively controlled during demolition, as well as after the appropriate clean-up was competed.
Result: Successful repairs addressing the cause of the condensation and the moldy conditions were made in the affected patient rooms.Uncategorized