Construction/renovation can endanger workers

Pathogens, indoor air quality present major issues

Construction or renovation can be annoying to employees in any workplace, but in the hospital environment such projects can threaten the health and safety of workers who daily are exposed to increased risks of poor indoor air quality and nosocomial pathogens such as Aspergillus, Mycobacterium tuberculosis, and varicella-zoster virus.

While maintaining adequate indoor air quality often is the primary issue, several reports indicate that Aspergillus and Legionella outbreaks have been caused by construction and renovation in hospitals.1-8 Although most reports focus on patient illness and mortality, hospital employees can be subject to the same health hazards, says Patrick Hartley, MB, assistant professor of clinical internal medicine at the University of Iowa in Iowa City and director of the workers’ health clinic at the university’s hospitals and clinics, where a number of construction and renovation projects have taken place in recent years.

Immunosuppressed HCWs face serious risks

"Not much is written about health care workers [during workplace construction and renovation]," Hartley notes. "One assumes that the health care worker is a healthy individual, but all bets are off if the health care worker is immunosuppressed, for example from HIV disease or leukemia or if on long-term steroids for asthma. There have been a number of outbreaks [reported in the literature] of fungal infections in bone marrow transplant units among patients who are immunosuppressed. Anybody who is immunosuppressed in that type of environment is at risk, so health care workers can be as much at risk as some of the patients if their immunity is not normal."

The main focus should be on maintaining standards of isolation, infection control, and air quality, and to control and isolate areas under construction, Hartley says.

Indoor air quality problems can be the same for hospital employees as for workers in office buildings. When construction or renovation is under way, every effort should be made to preserve indoor air quality. Hospitals have the added challenge of protecting patients who are at risk, as well keeping infectious patients from infecting HCWs or other patients, but "if adequate air quality and adequate isolation of infected individuals are maintained throughout the period of construction, there should not be any additional risk," he states.

Most complaints hospital employees tend to report during construction periods consist of upper airway problems from dust inhalation, such as cough, irritated throat, and runny eyes, he adds. However, workers with serious conditions such as pre-existing asthma could become more symptomatic. In those cases, workers can be temporarily accommodated by reassignment to another area of the hospital, or even permitted to work at home if possible.

"Sometimes it’s necessary to have safety personnel, an engineer, or an industrial hygienist look at the heating and ventilation system because there may need to be more air exchanges or a temporary air-handling system installed. If dust is blowing air from the area under construction, that’s not optimal. It’s prudent when there is ongoing construction to review the air-handling system in that area and make sure construction dust is not going to be spread to remote areas through the system because of the way it’s designed in your institution. [Doing this] review when the work is being set up can help spot problems before they occur," Hartley advises.

Brenda A. Barr, RN, MS, CIC, a nurse epidemiologist at the University of Iowa Hospitals and Clinics and author of a recent article on infection control issues in hospital construction and renovation,9 says HCWs are at the same risk as patients and visitors. Barr’s report enumerates a number of potential construction-related health hazards, including bacterial or fungal microorganisms in dust and dirt, which can contaminate water and air-handling systems; breaches in routine infection control measures, such as hand washing, if water systems are shut down temporarily; and transmission of M. tuberculosis, Aspergillus species, Legionella pneumophila, and varicella-zoster virus through improperly protected air-handling systems.

Aspergillus spores, a common mold, adhere to dust that becomes dislodged from ceiling tiles during construction and renovation. This spore-laden dust contaminates horizontal surfaces and subjects susceptible workers, patients, and visitors to the possibility of acquiring intractable pneumonia, Barr tells Hospital Employee Health.

"Out of concern for health care workers, as well as patients and visitors, we try to keep dust at a minimum on a floor when construction is going on," she says. "Sometimes we will have work done in the evening when there are fewer visitors and staff because no office personnel are there."

Barr emphasizes the importance of providing an inservice for contractors. The inservice should stress the importance of controlling dust and isolating areas under construction in a hospital, a practice endorsed by experts at the National Institute for Occupational Safety and Health (NIOSH) in Cincinnati.

Isolate work areas from occupied areas

While no procedures are established specifically for hospital construction and renovation practices, Ken Wallingford, CIH, indoor environmental quality research coordinator for NIOSH, recommends two references for ensuring adequate indoor air quality. One is the 1995 edition of IAQ Guidelines for Occupied Buildings Under Construction, by the Sheet Metal and Air-Conditioning Contractors National Association in Chantilly, VA [Telephone: (703) 803-2980]; the other is a paper published by the American Society for Heating, Refrigerating, and Air-Conditioning Engineers in Atlanta (Kuehn T. Construction/renovation influence on indoor air quality. ASHRAE J 1996; 38:22-29).

When areas adjacent to hospital construction or renovation projects remain occupied, the main problem is isolating project areas from occupied areas, Wallingford says. Isolation of construction areas in hospitals is more critical than in other buildings due to the need to protect patients and maintain optimal use of critical areas such as operating rooms, emergency rooms, laboratories, sterilizing rooms, and food preparation areas. For that reason, Wallingford has prepared a list of steps hospitals can follow, beginning from construction project planning and continuing through to completion. (See NIOSH guidelines, p. 125.)

"When that’s not done properly, you have indoor air quality problems that affect the people who work in the building," he explains. "Nothing from the work area should get into the occupied area, either through the ventilation system or through conduits between walls, but no matter how well you plan or how well-trained the contractors or subcontractors are, something always goes wrong. You need someone on site who will be responsible for maintaining adequate indoor air quality for occupants and who can take corrective action as needed."

When construction areas are not isolated, occupied spaces can be invaded by construction dust, organic vapors, and water. Many of these have odors that irritate employees and can contaminate their work areas, he notes. In addition to "nuisance" complaints such as itchy eyes or runny noses, people predisposed to allergies can experience respiratory problems. Besides the potential for dispersing pathogens such as Aspergillus, construction projects can dislodge and scatter latex glove powder particles that have settled in seldom-cleaned spaces along with other dust, which would be hazardous to latex-sensitive employees.

"It’s the responsibility of people managing health care facilities to protect workers," Wallingford says.


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