When water intrusion occurs in hospitals and other healthcare facilities and mold grows indoors in damp or water-damaged materials, it can cause a variety of health and safety concerns. Adverse effects occur to the occupants and buildings that it impacts. Although healthcare facilities managers can expect to find mold spores floating around in the indoor air in numbers and types that are similar to those found outdoors, they do not want mold growing indoors.
How does mold begin to grow?
Mold can often grow out of sight and unnoticed. For molds to grow, they basically need a food source — organic material such as dust, paper, drywall, wood — and moisture. Because molds grow by digesting organic material, they will eventually destroy whatever they grow on, and because organic matter is almost always available, moisture or dampness in building materials is the limiting factor determining whether it can grow.
Buildings have a large number of spaces that meet the criteria for mold development that include large wall and ceiling cavities where mold can grow undetected, along with extensive plumbing and HVAC systems that provide the final ingredient needed — moisture.
Mold almost certainly will grow inside buildings whenever moisture intrusion occurs through flooding, condensation and plumbing or roof leaks. Even when the moisture source is removed, if mold began growing on a building surface while it was still wet, the spores will remain there and potentially cause allergic reactions or other health effects until they are physically removed.
Spraying surface growth with a 1:10 bleach solution might kill and whiten mold spores, but it is important to note that even dead spores can cause allergic reactions in sensitive individuals. Furthermore, visible surface growth is often just a symptom that even more mold is hidden within the cavities.
Health effects and control incentives
Overwhelming incentives are involved with managing moisture intrusion and mold indoors. Not only can mold cause structural damage costing money and potential lost revenue. Elevated levels of airborne mold also have been directly attributed to adverse health effects in water damaged buildings as well as healthcare-associated infections (HAIs) in healthcare settings.
Unfortunately, research has shown that some HAIs have resulted in patient deaths. Mold remediation and building repairs associated with moisture intrusion can cost a facility tens to hundreds of thousands of dollars. Taking these consequences into consideration, operations staff in water-damaged buildings are well incentivized to manage the impact of mold effectively and proactively in their facilities.
Agencies such as state health departments, the Institute of Medicine (IOM), the U.S. Centers for Disease Control and Prevention (CDC), and the World Health Organization (WHO), among other professionals, agree that dampness and mold cause adverse health effects. Such health effects may include:
- upper respiratory symptoms, including sore or irritated nose or throat and congested nose or sinuses
- lower respiratory symptoms, including difficulty breathing, cough, shortness of breath and wheezing
- respiratory infections, including acute bronchitis
- asthma attacks in those with asthma and causation of new asthma
- allergic rhinitis, including runny or congested nose and sneezing
- eye irritation, such as reddening, burning and watering
- skin rashes, irritation and eczema.
Popular press highlights toxic black mold. But while certain molds are considered toxigenic and can produce mycotoxins, not all molds produce these toxins. Individuals with suppressed immune systems or underlying lung disease, such as those in healthcare facilities, are more susceptible to fungal infections, and exposure to certain types of pathogenic molds can result in health complications. For example, Aspergillus is found indoors and outdoors, and their transmission occurs through inhalation of airborne conidia. According to the National Center for Biotechnical Information, invasive aspergillosis is a leading cause of infection-related death in immunocompromised patients.
Looking for guidance
To date, no federal or state policies have set safe exposure limits to airborne mold or quantify the health risks from dampness and mold in buildings. But scientific research on the relationship between mold exposures and health effects is ongoing and certain codes exist to increase awareness and reduce exposure to hazards from indoor dampness and mold.
For example, the Department of Public Health (CDPH) says it “agrees with other building and health professionals that indoor dampness, water intrusion or fungal growth should always be eliminated in a safe and efficient manner.”
Several other states require mold remediation licensing or regulate mold remediation businesses in some way. Some states establish minimum standards for mold remediation companies based on general mold remediation principles set forth by various agencies. Certain states might even take civil action against mold remediation companies that violate their law’s provisions and require statewide education and outreach programs on indoor air quality (IAQ) and mold.
Control and prevention efforts
It is crucial to focus on control and prevention efforts. Healthcare facilities managers must ensure proper maintenance of HVAC systems and constantly be on the lookout for signs of moisture on ceilings, walls, under-sink cabinets and floors.
Since water generally follows the path of least resistance, regular inspections should take this into consideration and ensure all areas are inspected, no matter how insignificant they might seem. These affected areas can be inside ductwork or hidden within wall and ceiling cavities. Technicians should be careful when removing or replacing water-damaged building materials to prevent releasing mold spores and to protect occupants from unnecessary exposure.
It is important to note that the level of health risk can not be determined by air sampling alone because either by the type or amount of mold present, effects on people can vary greatly. So managers generally do not need to know the type of mold growing indoors to determine whether remediation is appropriate because no matter the type or color, some type of remediation will be necessary.
For details on addressing mold and moisture intrusion, managers can contact theU.S. Environmental Protection Agency, the U.S. Occupational Safety and Health Administration (OSHA), AIHA, the Institute of Inspection, Cleaning and Restoration Certification and the CDC.
Involving an industrial hygienist
If known or suspected water intrusion is reported, managers should consult a qualified industrial hygienist (IH) to help assess whether an indoor mold growth source is suspected. The primary objectives of the investigation and response effort should at least include:
- finding and identifying the sources of moisture intrusion
- drying damp materials within 24-48 hours
- making repairs to prevent future mold growth from recurring
- bringing in a qualified mold remediation contractor to perform mold remediation in accordance with generally accepted industry guidelines.
This is generally accomplished through visual investigations, moisture content measurements, the reported history of moisture intrusion and associated drying efforts, and sometimes the collection of airborne and surface mold spore samples for confirmation. Managers must keep in mind that air sampling alone for airborne molds should not be used to determine the level of health risks, the general condition or structural integrity of the indoor environment. The steps described in the assessment above at the least should all be considered.
In general, porous materials that have been affected by mold growth such, as drywall, moisture barrier paper, insulation, carpeting and ceiling tiles, should be removed under controlled conditions and discarded. Depending on the amount of visible mold growth present, negative pressure containment provisions with HEPA-filtered air machines might be necessary to prevent the dispersion of mold spores from contaminating surrounding areas. Cleanable non-porous and semi-porous surfaces, such as wood, tile, stone, plastic and metal, can be HEPA vacuumed and scrubbed clean with soapy water and a bristle brush.
Control the source
Managers can avoid costly remediation associated with water-damaged building materials by addressing moisture intrusion quickly. Every effort must be made to immediately dry all affected building materials before mold growth begins to develop, which is generally within 24-48 hours.
Managers should consult with an IH as soon as moisture intrusion occurs. The IH should conduct an initial inspection, provide recommendations for remediation with oversight if necessary, and perform post-remediation inspections and testing prior to build-back to help assess whether remediation efforts were effective.
The investigation and subsequent remediation process is a team effort. To avoid potential conflicts of interest and to ensure a successful outcome, it is in the client’s best interest to keep the recommendation, oversight and scope development process performed by the IH separate from actual remediation performed by qualified remediation contractors. Hiring two separate entities to perform these services will control potentially costly follow-ups.
Nicole Naggar is an environmental health specialist with NV5 Engineering.