Health hazard evaluation report: HETA-2005-0346-3008, Dixie Regional Medical Center, Saint George, Utah.
The National Institute for Occupational Safety and Health (NIOSH) received a confidential Health Hazard Evaluation (HHE) request on August 23, 2005 from Intermountain Health Care (IHC) employees working at Dixie Regional Medical Center (DRMC) in Saint George, Utah. The request reported concerns about inadequate maintenance practices and poor indoor air quality (IAQ), including excess water and mold growth in heating and air conditioning units and in a crawlspace under one of the buildings. Employee health problems included lung, immune system, and skin ailments. The HHE was originally closed with a letter to the requesters on September 1, 2005. Due to continued occupational health concerns of the requesters, the HHE reopened in January 2006. NIOSH staff visited DRMC on January 30-31, 2006. DRMC is comprised of two separate facilities, River Road Campus and 400 East Campus. The HHE requesters reported concerns at both. At the River Road Campus, there was concern about potential mold exposures related to a water leak in the crawlspace under the building. Requesters reported that leaking high-pressure ventilation ductwork running through the crawlspace created positive pressure causing air to flow from the crawlspace into the hospital. At the 400 East Campus, requesters were concerned about uncontrolled renovations that might have allowed contaminants to enter patient care areas and employee workspaces. Additionally, there were numerous concerns with the 400 East heating, ventilating, and air conditioning (HVAC) systems resulting in possible dust and mold exposures. Poor maintenance practices resulting in dirty/moldy ductwork and filters, improper or missing filters, and standing water in the air handling units (AHUs) were also reported. NIOSH found both campuses to be generally clean and well-maintained. The crawlspace area at River Road was dry with no visible mold present. Any mold growth that had occurred during the water leak had been remediated. A borate-based fungicide had been applied to the support columns and some areas of the soil floor. To help rapidly detect any future water leaks (or incursion from the outside) in the crawlspace, DRMC installed a modular-zone water-detection system complete with seven moisture sensing cables. Additionally, proper air vents and small fans had been installed in the crawlspace to help keep the area dry. The HVAC systems at River Road were clean and functioning properly, with correct filter configurations installed in each. Multiple structural changes and renovations at the 400 East campus had resulted in 13 different AHUs of various age from various manufacturers. Each unit had filters installed in the correct configuration during the NIOSH visit, and no filters appeared excessively dirty or damaged. Many of the 400 East AHUs were installed without allowing the height needed for proper condensate drainage. There was rust from standing water resulting from the overflow of drain pans. The facilities manager stated that standing water is typical during the rainy season of late summer and early fall when high outdoor humidity overwhelms the ability of the AHUs to remove moisture from the incoming air. The facilities manager also stated that during these periods, excess condensation from cooling coils can cause the filters to become saturated with water that might facilitate mold growth. However, during NIOSH's visit in January, no mold growth or wetted filters were found. Suspected mold growth was found in the rooftop mechanical room housing AHU 4th West. We conducted a video examination of the interior ventilation ductwork on the third floor of the 400 East building. The air supply duct was clean and free from any visible dirt deposits. The return ductwork had visible accumulations of lint attributed to the high volume of linens that are used by the hospital. Aside from the lint, there was no excess dirt or evidence of mold growth seen during the duct examination. NIOSH conducted a site visit at the River Road and 400 East Campuses of Dixie Regional Medical Center in Saint George, Utah to address employee concerns about water incursion and inadequate maintenance that might be adversely impacting the indoor air quality at their workplace. NIOSH found evidence of previous water incursion in the River Road crawlspace and in some air handling units at the 400 East Campus. Water-monitoring equipment had been installed in the crawlspace to detect future leaks. Modifications were planned for air handlers known to retain water during the wet season. Management had implemented policies and procedures to ensure better monitoring of areas prone to water incursion and identified a contact person for employee concerns.