Mold & the Coatings Connection
A closer look at the role of paints in mold prevention reveals challenges and opportunities for managers
Addressing mold in institutional and commercial facilities can be simple or complex, routine or controversial. No consensus exists among environmental professionals, hygienists and healthcare professionals as to the acceptable level of mold exposure in indoor environments. Research does not conclusively indicate that mold can cause illness in a typically healthy individual.
Evidence exists to document severe health effects of fungi in humans, but most of the evidence comes from ingestion of contaminated foods or occupational exposures in agricultural settings. With the possible exception of mold remediation in very heavily contaminated indoor areas, such high-level exposures generally don’t occur while performing typical mold remediation work.
But even without a consensus on health effects, testing methods and remediation procedures, the mold profession continues to thrive. So how should maintenance and engineering managers react to the discovery of mold without overreacting?
While many aspects of the situation have been explored, managers should take a closer look at the role paints and coatings play in the process.
Setting a Strategy
Determining mold-remediation strategies can be simple. Consider the following guidance from the Occupational Safety and Health Administration (OSHA) in its safety and health information bulletin on mold:
In most cases, mold testing is unnecessary when visible mold is present.
Air sampling for mold might not be part of a routine assessment because decisions about appropriate remediation strategies often can be made on the basis of a visible inspection.
And according to the U.S. Environmental Protection Agency, no practical method exists to eliminate all mold and mold spores indoors; the way to control indoor mold growth is to control moisture.
If the mold is visible, workers certainly should remove it, but managers must decide on the tactics and scope of the project. But a more cost-effective strategy is to prevent mold growth in the first place.
Paints and coatings can be useful in simplifying mold issues in buildings. Lead-based paint is a good example of old-school moisture and mold protection. It protected surfaces from moisture, resulting in its use in kitchens, bathrooms, windows, doorways and exteriors. It adhered well to surfaces exposed to weather, and the lead component helped minimize mold growth.
Newer paints and coatings can protect surfaces from moisture infiltration and damage, and they are especially useful on porous surfaces such as drywall, particleboard, and wood, and they can make surfaces easier to clean.
But they also might have drawbacks. Many are treated with chemicals or biocides that can prevent or retard mold growth, at least temporarily. These anti-microbial coatings can be used as a combination lockdown and preventive measure, but this feature can unintentionally hide or delay future mold growth temporarily. Unscrupulous contractors have used treated coatings to pass post-remediation testing and hide poor mold-remediation and cleaning work practices.
As with lead paint, treated coatings also can have unintended consequences for building occupants. Many occupants have allergic reactions to chemicals that are more severe than those reactions to mold.
Also, workers applying treated coatings should take precautions by reading the material safety data sheets supplied with the products. Work areas should always be properly ventilated, and managers should also consider the use of appropriate personal protective equipment for employees.
Some coatings treated with biocides are considered pesticides, and some states require that only registered pesticide applicators apply these products in schools and commercial buildings. Managers should make sure that anyone applying biocides is properly licensed where required. Proper cleaning procedures and moisture control should eliminate the need for an anti-microbial coating. But occupant peace of mind can influence the use of these products in certain applications.
Mold growth generally requires four components: moisture, temperature, mold spores and food.
Indoor temperatures must be maintained to ensure building comfort, mold spores are almost impossible to control, and many common building furnishings and construction components provide good food sources.
So, moisture tends to be the easiest of the four components to control. What are moisture sources in buildings? Water leaks and spills can contribute significant amounts of moisture into a building. Water vapor, on the other hand, enters indoor spaces through respiration by building occupants and humidifiers and through the air itself.
Focusing on moisture issues doesn’t entirely eliminate existing mold. So managers will need to develop a cleanup and prevention program.
Clean-up should focus on removing mold to prevent occupant exposures and damage to building components and furnishings. The program should not just focus on killing the mold but instead should focus on the mold contamination. Dead and inactive mold spores can still be allergenic to building occupants, and even dead mold spores contain chemicals and proteins that can cause a reaction in humans.
Cleaning work methods include use of wet-vacuums, HEPA vacuums, damp wiping, and disposal of components and materials. Materials that are non-porous — metals, glass, and hard plastics— and those that are semi-porous — wood and concrete — that are structurally sound and visibly moldy can be cleaned and reused.
Cleaning can be performed by simply using a detergent solution. But workers should remove and discard porous materials such as ceiling tiles, insulation and drywall with more than a small area of contamination. Some porous materials such as fabrics can be cleaned and reused, but they should be discarded if possible.
Managers should ensure that reused materials are dry and visibly free from mold. Follow-up inspections can assure the effectiveness of the restoration work on mold. Managers also can contact a professional restoration consultant when restoring porous materials.
Finally, managers should weigh the benefits and drawbacks of anti-microbial and biocides. The EPA recommends against using a biocide, such as chlorine bleach, as a routine practice during mold remediation, although there might be instances where professional judgment indicates its use, such as when immune-compromised individuals are present.
Dead, or non-viable, mold spores still can cause undesirable allergy symptoms in building occupants and visitors. Managers can find additional guidance for developing and implementing work practices and protecting workers during mold remediation at the OSHA web site, www.osha.gov/dts/shib/ shib101003.html. Managers can find guidance for controlling moisture in buildings at the EPA’s web site, www.epa.gov/iaq/largebldgs/graphics/ appenc.pdf.
Response to mold does not have to be complicated. Managers will benefit from reading easily obtained documents from the EPA, OSHA and other public and private sources, including manufacturers. Solving the source of mold growth — moisture — should be the main emphasis of any remediation or preventive action. Proper cleaning strategies further protect occupants and workers from unwanted exposures to irritants from molds, cleaners and coatings.
Finally, selecting paints and coatings that complement the organization’s mold-management program can prevent mold-causing problems in the first place.
Managers should consider these pointers in developing and implementing a mold prevention and remediation program:
- Potential health effects and symptoms associated with mold exposures include allergic reactions, asthma and other respiratory complaints.
- No practical way exists to eliminate all mold and mold spores indoors. The way to control indoor mold growth is to control moisture.
- Fix the source of the water problem or leak to prevent mold growth.
- Reduce indoor humidity to 30-60 percent to decrease mold growth by venting moisture-generating sources to the outside; using air conditioners and dehumidifiers; increasing ventilation; and using exhaust fans.
- Clean and dry any damp or wet building materials and furnishings within 24-48 hours to prevent mold growth.
- Clean mold from hard surfaces with water and detergent, and dry the surfaces completely. Mold- absorbent materials such as ceiling tiles might need replacement.
- Add insulation to prevent condensation by reducing the potential for condensation on cold surfaces, such as windows, piping, exterior walls, roof and floors.
- Avoid installing carpeting in areas of perpetual moisture problems, such as by drinking fountains or classroom sinks, or on concrete floors with leaks.
Jeffery C. Camplin, CSP, CPEA, is president of Camplin Environmental Services Inc., a safety and environmental consulting firm in Rosemont, Ill. He also is administrator of the American Society of Safety Engineers (ASSE) Environmental Practice Specialty, for which he is developing an ANSI standard on worker protection during mold-remediation activities.