Guidelines on Assessment and Remediation of Fungi in Indoor Environments - Part 3

Remediation
The goal of remediation is to remove or clean mold-damaged materials using work practices that protect occupants by controlling the dispersion of mold from the work area and protect remediation workers from exposures to mold. The listed remediation methods were designed to achieve this goal; however, they are not meant to exclude other similarly effective methods and are not a substitute for a site-specific work plan. Since little scientific information exists that evaluates the effectiveness and best practices for mold remediation, these guidelines are based on principles used to remediate common indoor environmental hazards. These guidelines are not intended for use in critical care facilities such as intensive care units, transplant units, or surgical suites.

Prior to any remediation, consideration must be given to the potential presence of other environmental hazards, such as asbestos and lead. These guidelines are based on possible health risks from mold exposure and may be superseded by standard procedures for the remediation of other indoor environmental hazards.

Moisture Control and Building Repair

In all situations, the underlying moisture problem must be corrected to prevent recurring mold growth. Indoor moisture can result from numerous causes, such as: façade and roof leaks; plumbing leaks; floods; condensation; and high relative humidity. An appropriate building expert may be needed to identify and repair building problems. An immediate response and thorough cleaning, drying, and/or removal of water-damaged materials will prevent or limit microbial growth.

Relative humidity should generally be maintained at levels below 65% to inhibit mold growth.19 Short-term periods of higher humidity would not be expected to result in mold growth.20 However, condensation on cold surfaces could result in water accumulation at much lower relative humidity levels. Relative humidity should be kept low enough to prevent condensation on windows and other surfaces.

Emphasis should be placed on ensuring proper repairs of the building infrastructure so that water intrusion and moisture accumulation is stopped and does not recur.

Worker Training

Proper training of workers is critical in successfully and safely remediating mold growth.21,22 Training topics that should be addressed include:

Causes of moisture intrusion and mold growth
Health concerns related to mold exposure
The use of appropriate personal protective equipment
Mold remediation work practices, procedures, and methods
For additional information, the National Institute of Environmental Health Sciences’ publication, “Guidelines for the Protection and Training of Workers Engaged in Maintenance and Remediation Work Associated with Mold” lists minimum training criteria for building maintenance and mold remediation workers that should be completed before addressing indoor mold growth.23

Trained building maintenance staff can address limited and occasional mold growth. For larger jobs, more extensively trained mold remediation workers may be needed.

Cleaning Methods

Non-porous materials (e.g. metals, glass, and hard plastics) can almost always be cleaned. Semi-porous and porous structural materials, such as wood and concrete can be cleaned if they are structurally sound. Porous materials, such as ceiling tiles and insulation, and wallboards (with more than a small area of mold growth) should be removed and discarded. Wallboard should be cleaned or removed at least six inches beyond visually assessed mold growth (including hidden areas, see Visual Inspection) or wet or water-damaged areas.24 A professional restoration consultant should be contacted to restore valuable items that have been damaged.

Cleaning should be done using a soap or detergent solution. Use the gentlest cleaning method that effectively removes the mold to limit dust generation. All materials to be reused should be dry and visibly free from mold. Consideration should also be given to cleaning surfaces and materials adjacent to areas of mold growth for settled spores and fungal fragments. A vacuum equipped with a High-Efficiency Particulate Air (HEPA) filter could also be used to clean these adjacent areas.

Disinfectants are seldom needed to perform an effective remediation because removal of fungal growth remains the most effective way to prevent exposure. Disinfectant use is recommended when addressing certain specific concerns such as mold growth resulting from sewage waters. If disinfectants are considered necessary, additional measures to protect workers and occupants may also be required. Disinfectants must be registered for use by the United States Environmental Protection Agency (EPA). Any antimicrobial products used in a HVAC system must be EPA-registered specifically for that use.

The use of gaseous, vapor-phase, or aerosolized (e.g. fogging) biocides for remedial purposes is not recommended. Using biocides in this manner can pose health concerns for people in occupied spaces of the building and for people returning to the treated space. Furthermore, the effectiveness of these treatments is unproven and does not address the possible health concerns from the presence of the remaining non-viable mold.

Quality Assurance Indicators

Measures to ensure the quality and effectiveness of remediation should be undertaken regardless of the project size. Evaluations during as well as after remediation should be conducted to confirm the effectiveness of remedial work, particularly for large-scale remediation. At minimum, these quality assurance indicators should be followed and documented:

The underlying moisture problem was identified and eliminated
Isolation of the work area was appropriate and effective
Mold removal and worksite cleanup was performed according to the site-specific plan
Any additional moisture or mold damage discovered during remediation was properly addressed
Upon completion of remediation, surfaces are free from visible dust and debris.
If environmental sampling was performed, the results of such sampling were evaluated by a trained building or environmental health professional.10
Restoring Treated Spaces

After completing mold remediation and correcting moisture problems, building materials that were removed should be replaced and brought to an intact and finished condition. The use of new building materials that do not promote mold growth should be considered. Anti-microbial paints are usually unnecessary after proper mold remediation. They should not be used in lieu of mold removal and proper moisture control, but may be useful in areas that are reasonably expected to be subject to moisture.

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Hidden Mold

You may suspect hidden mold if a building smells moldy, but you cannot see the source, or if you know there has been water damage and residents are reporting health problems. Mold may be hidden in places such as the back side of dry wall, wallpaper, or paneling, the top side of ceiling tiles, the underside of carpets and pads, etc. Other possible locations of hidden mold include areas inside walls around pipes (with leaking or condensing pipes), the surface of walls behind furniture (where condensation forms), inside ductwork, and in roof materials above ceiling tiles (due to roof leaks or insufficient insulation).

Investigating hidden mold problems

Investigating hidden mold problems may be difficult and will require caution when the investigation involves disturbing potential sites of mold growth. For example, removal of wallpaper can lead to a massive release of spores if there is mold growing on the underside of the paper. If you believe that you may have a hidden mold problem, consider hiring an experienced professional.

Cleanup and Biocides

Biocides are substances that can destroy living organisms. The use of a chemical or biocide that kills organisms such as mold (chlorine bleach, for example) is not recommended as a routine practice during mold cleanup. There may be instances, however, when professional judgment may indicate its use (for example, when immune-compromised individuals are present). In most cases, it is not possible or desirable to sterilize an area; a background level of mold spores will remain - these spores will not grow if the moisture problem has been resolved. If you choose to use disinfectants or biocides, always ventilate the area and exhaust the air to the outdoors. Never mix chlorine bleach solution with other cleaning solutions or detergents that contain ammonia because toxic fumes could be produced.

Moisture and Mold Prevention and Control Tips

When water leaks or spills occur indoors - ACT QUICKLY. If wet or damp materials or areas are dried 24-48 hours after a leak or spill happens, in most cases mold will not grow.

Clean and repair roof gutters regularly.

Make sure the ground slopes away from the building foundation, so that water does not enter or collect around the foundation.

Keep air conditioning drip pans clean and the drain lines unobstructed and flowing properly.

Keep indoor humidity low. If possible, keep indoor humidity below 60 percent (ideally between 30 and 50 percent) relative humidity. Relative humidity can be measured with a moisture or humidity meter, a small, inexpensive ($10-$50) instrument available at many hardware stores.

If you see condensation or moisture collecting on windows, walls or pipes ACT QUICKLY to dry the wet surface and reduce the moisture/water source. Condensation can be a sign of high humidity.

Actions that will help to reduce humidity

• Vent appliances that produce moisture, such as clothes dryers, stoves, and kerosene heaters to the outside where possible. (Combustion appliances such as stoves and kerosene heaters produce water vapor and will increase the humidity unless vented to the outside.)
  
• Use air conditioners and/or de-humidifiers when needed.
  
• Run the bathroom fan or open the window when showering. Use exhaust fans or open windows whenever cooking, running the dishwasher or dishwashing, etc.

Actions that will help prevent condensation

• Reduce the humidity.
  
• Increase ventilation or air movement by opening doors and/or windows, when practical. Use fans as needed.
  
• Cover cold surfaces, such as cold water pipes, with insulation.
  
• Increase air temperature.

Renters: Report all plumbing leaks and moisture problems immediately to your building owner, manager, or superintendent. In cases where persistent water problems are not addressed, you may want to contact local, state, or federal health or housing authorities. [Note: Find your state health department contacts at www.epa.gov/iaq/whereyoulive.html.]

Testing or Sampling for Mold

Is sampling for mold needed? In most cases, if visible mold growth is present, sampling is unnecessary. Since no EPA or other federal limits have been set for mold or mold spores, sampling cannot be used to check a building's compliance with federal mold standards. Surface sampling may be useful to determine if an area has been adequately cleaned or remediated. Sampling for mold should be conducted by professionals who have specific experience in designing mold sampling protocols, sampling methods, and interpreting results. Sample analysis should follow analytical methods recommended by the American Industrial Hygiene Association (AIHA), the American Conference of Governmental Industrial Hygienists (ACGIH), or other professional organizations.

A Brief Guide to Mold, Moisture, and Your Home

Why is mold growing in my home?

Molds are part of the natural environment. Outdoors, molds play a part in nature by breaking down dead organic matter such as fallen leaves and dead trees, but indoors, mold growth should be avoided. Molds reproduce by means of tiny spores; the spores are invisible to the naked eye and float through outdoor and indoor air. Mold may begin growing indoors when mold spores land on surfaces that are wet. There are many types of mold, and none of them will grow without water or moisture.

Can mold cause health problems?

Molds are usually not a problem indoors, unless mold spores land on a wet or damp spot and begin growing. Molds have the potential to cause health problems. Molds produce allergens (substances that can cause allergic reactions), irritants, and in some cases, potentially toxic substances (mycotoxins). Inhaling or touching mold or mold spores may cause allergic reactions in sensitive individuals. Allergic responses include hay fever-type symptoms, such as sneezing, runny nose, red eyes, and skin rash (dermatitis). Allergic reactions to mold are common. They can be immediate or delayed. Molds can also cause asthma attacks in people with asthma who are allergic to mold. In addition, mold exposure can irritate the eyes, skin, nose, throat, and lungs of both mold-allergic and non-allergic people. Symptoms other than the allergic and irritant types are not commonly reported as a result of inhaling mold. Research on mold and health effects is ongoing. This brochure provides a brief overview; it does not describe all potential health effects related to mold exposure. For more detailed information consult a health professional. You may also wish to consult your state or local health department.

How do I get rid of mold?

It is impossible to get rid of all mold and mold spores indoors; some mold spores will be found floating through the air and in house dust. The mold spores will not grow if moisture is not present. Indoor mold growth can and should be prevented or controlled by controlling moisture indoors. If there is mold growth in your home, you must clean up the mold and fix the water problem. If you clean up the mold, but don't fix the water problem, then, most likely, the mold problem will come back.

Source:  Environmental Protection Agency

About Molds and Asthma

Molds are microscopic fungi that live on plant and animal matter. Molds can be found almost anywhere when moisture is present.

Molds create tiny spores to reproduce, just as plants produce seeds. Mold spores float through the indoor and outdoor air continually. When mold spores land on damp places indoors, they may begin growing.

For people sensitive to molds, inhaling mold spores can trigger an asthma attack.

 Actions you can take

• If mold is a problem in your home, you need to clean up the mold and eliminate sources of moisture.
• If you see mold on hard surfaces, clean it up with soap and water. Let the area dry completely.
• Use exhaust fans or open a window in the bathroom and kitchen when showering, cooking or washing dishes.
• Fix water leaks as soon as possible to keep mold from growing.
• Dry damp or wet things completely within one to two days to keep mold from growing.
• Maintain low indoor humidity, ideally between 30-50% relative humidity. Humidity levels can be measured by hygrometers, which are available at local hardware stores.

Source:  Environmental Protection Agency

Frequently Asked Mold Questions

What causes mold to develop?
Mold requires nutrients, water, oxygen and favorable temperatures to grow. Nutrients for mold are present in dead organic material such as wood, paper or fabrics; mold can also derive nutrients from some synthetic products such as paints and adhesives. Mold requires moisture, although some mold species can obtain that moisture from moist air when the relative humidity is above 70 per cent. Many molds thrive at normal indoor temperatures; few if any molds are able to grow below 40 F or above 100 F. Outside this range molds may remain dormant or inactive; they may begin to grow again when the temperature is more favorable. Temperatures well above 100 F will kill mold and mold spores, but the exact temperature required to kill specific species is not well established.

How does mold get into a building?
Molds are decomposers of organic material such as wood, plants and animals. Mold and mold spores are found in high concentrations wherever there is dead matter such as a pile of leaves, manure or compost. Mold spores enter buildings through the air or on people, animals and objects that are brought into the building. Spores are small bundles of genetic material and chemicals (similar to seeds) that molds make under certain conditions.

Are there harmful and non-harmful molds?
There are only a few molds that can cause infection in healthy humans. Some molds cause infections only in people with compromised immune systems. The biggest health problem from exposure to mold is allergy and asthma in susceptible people. There are more than 100,000 types of mold. Good information has been developed for only a small number of these molds – at least in terms of their effects on human health. Most people tolerate exposure to moderate levels of many different molds without any apparent adverse health effects.

Some molds produce powerful chemicals called “mycotoxins” that can produce illness in animals and people. Scientific knowledge about the health effects of these toxins on humans is quite limited.

Does mold affect everyone the same way?
No. Some individuals have a genetic makeup that puts them at risk for developing allergies to mold. People who have an allergy to mold, especially if they also have asthma, can become ill from exposure to a small amount of mold. Individuals also seem to be quite different in their response to exposure to the toxic chemicals that some molds release. These differences between individuals contribute to the difficult question of determining safe exposure limits for mold.

How much mold exposure is harmful?
No one knows the answer to this question for several reasons. Individuals are very different with respect to the amount of mold exposure they can tolerate. Children under the age of one year may be more susceptible to the effects of some molds than older individuals. Measuring or estimating “exposure” levels is very difficult. “Exposure” means the amount of mold (microscopic spores and mold fragments) that gets into a person usually by breathing, but also by eating or absorption through the skin. For example, a building may have a lot of mold in the walls but very little of that mold is getting into the air stream. In that case the people working or living in that building would have little mold exposure.

Can mold exposure cause brain damage or death?
Although some “experts” claim that individuals have brain damage or have died because of exposure to mold and especially mold toxins, there is no good science at this time to support these claims. Consequently it is prudent to minimize one’s exposure to really moldy environments. By “really moldy” we mean where there are large visible areas of mold (more than a few square feet) or the building has a “musty” odor because of hidden mold growth. There are many epidemiological studies showing that people who live in houses with dampness have many more health problems, especially respiratory, than do people who live in dry houses. This association does not “prove” that it is the mold that is responsible for the increase in illness. However, it does support the assertion that it is not wise to live in damp, moldy buildings.

Does tighter building construction promote mold development?
Tighter building construction does not by itself promote mold growth, but tight construction combined with some poor choices in design, building materials or operations can increase the probability of mold growth. What do we mean? The tighter the building construction the less air exchange there is between the inside air and the outside air. Whatever gets into the inside air stays there longer than it would in a house with loose construction. Moisture that gets into the air from activities such as cooking, bathing and even breathing will remain in a tight house longer than it would in a loose house. That’s why exhaust fans should be installed in bathrooms and kitchens and vented to the outside. Clothes dryers should also be vented to the outside.

Tight construction permits control of the air exchange between the inside and the outside and can prevent the deposition of moisture in walls and roofs. Controlling moisture, including indoor relative humidity is the key to preventing mold growth. Tight building construction when combined with source control of moisture (exhaust fans) and controlled ventilation (intentional introduction of outside air) reduces the probability of mold growth in a building. Controlled ventilation can be provided by a duct that brings outside air to the return side of the air handler of a forced air system. A timing device or fan cycler can be programmed to have the air handler turn on for a specified number of minutes each hour even when there is no call for heating or cooling. In cold climates controlled ventilation is frequently provided by a heat recovery ventilator (HRV).

Do new building materials (e.g. drywall or paper faced gypsum board) promote mold growth?
Mold needs water, a nutrient source, oxygen and favorable temperature to grow. Many species of mold love paper faced gypsum board. Why? Making paper involves the mechanical and chemical processing of wood. Paper is largely pre-digested so it is easy for mold to get nutrients from the paper. But unless there is enough moisture present mold can’t grow on the paper. If paper faced gypsum board is kept dry, it can be used and still not have mold. This material is kept dry by controlling the interior relative humidity, keeping rain from entering roofs and walls, and NOT using paper faced gypsum in areas that are likely to get wet. This means no paper faced gypsum board in shower and tub areas. Cement board, mortar or non-paper faced gypsum can safely be used in these damp areas because these products do not contain nutrients to support mold growth.

Are there reliable tests to indicate the presence of mold?
Almost all of us already have two effective mold detectors: our eyes and our noses. If black or green discoloration is noticed that is fuzzy in appearance and is in a location that is damp or had been damp, it is almost certainly mold. If a building smells musty, there probably is mold somewhere; the mold may be on boxes stored in a basement or in walls or in the crawl space. If you want to find mold, look for the presence of water or a location where water was likely to have been. If there is still any question about whether the black stuff is mold, have a reliable laboratory examine the material. All you need to know is whether mold is seen when the material is examined under the microscope.

An increasing number of companies are offering “air testing for mold.” On the surface this seems like a reasonable thing to do. The problem, however, is that the results of most air sampling for mold are meaningless for two reasons. Air sampling for mold was not developed to determine if an environment was safe or had a dangerous level of mold in the air. Air sampling was developed to help identify the location of a hidden reservoir of mold. If the source of mold is already identified, air sampling does not provide additional meaningful information. Furthermore, safe or toxic levels of air borne mold have not been established. An individual air sample for mold provides a “snapshot” of what was in the air during the few minutes of sampling. The results may not be indicative of the amount of mold that is in the air during most of the day.

Air sampling for mold should be done either to obtain an answer to a question that cannot be answered without the air sampling or to obtain data as part of a research project. The Center for Disease Control (CDC), the U.S. Environmental Protection Agency (EPA) and the American Conference of Governmental Industrial Hygienists do not recommend routine air testing for mold.

If mold is present, what’s the best way to get rid of it?
The answer depends on how much mold is present and where it is located. If the mold is on furnishings or boxes simply discard the materials. Moldy materials are not considered hazardous waste; they can be sent to a regular landfill. However, it is smart to seal the mold material in heavy plastic to protect the people who handle it in transit and prevent spreading large amounts of the mold into the building as you carry the material out of it.

If the mold is on a hard surface but occupies less than 10 square feet wash the area with soapy water (scrubbing with a brush may be necessary), rinse and allow the area to dry before repainting. If you have asthma, severe allergies and a weaken immune system get someone else to do the clean up.

Larger areas (greater than 10 square feet in area) should be cleaned by someone with experience in doing this type of work. Remember, determine what caused the moisture problem and correct that problem. Otherwise, mold is likely to recur.

Is it possible to completely eliminate mold from the inside of a home or office building?
The answer depends upon what is meant by “completely eliminate mold.” To keep a building completely free of mold spores requires very efficient air filtration and is only accomplished in special situations such as hospital operating rooms and manufacturing “clean rooms.” Remember, mold spores are in the outside air virtually all the time and some of them will get inside buildings.

However, it is possible to keep mold from growing inside a building. Moisture control is the key to controlling mold in interior spaces. Air filtration can contribute to lowering mold spores in the air but is secondary to moisture control.

Should I use bleach to get rid of mold?
No. Although bleach will kill and decolorize mold, it does not remove mold. Dead mold can still cause allergic reactions. It is not necessary to kill mold to remove mold. Soap and water and scrubbing can remove mold from hard surfaces. The Environmental Protection Agency (EPA), the Center for Disease Control (CDC) and the New York City Health Department agree that bleach or other biocides should not routinely be used to clean up mold.

How do I know when the mold clean up is finished?

The mold cleanup is finished when there is no visible mold remaining and there is no dust or dirt remaining that could contain large amounts of mold and mold spores. Routine clearance testing for mold is not necessary. Leaving a few mold spores behind is not a problem if the underlying moisture problem has been corrected. Remember that mold spores are virtually everywhere. Even if all mold and mold spores are removed as part of the cleanup, spores from outside will re-enter that space. The spores won’t be able to grow unless water is also present.

Guidelines on Assessment and Remediation of Fungi in Indoor Environments

This 2008 document revises existing guidelines and supersedes all prior editions. It is based both on a review of the current literature regarding fungi (mold) and on comments from a review panel consisting of experts in the fields of mycology/microbiology, environmental health sciences, environmental/occupational medicine, industrial hygiene, and environmental remediation.

These guidelines are intended for use by building owners and managers, environmental contractors and environmental consultants. It is also available for general distribution to anyone concerned about indoor mold growth. The attached fact sheet, “Mold Growth: Prevention and Cleanup for Building Owners and Managers,” is a simplified summary of these guidelines, which may be useful for building owners, managers and workers. It is strongly recommended that the complete guidelines be referred to before addressing the assessment or remediation of indoor mold growth... read more

MOLD ALErGY

Mold and mildew are fungi. They differ from plants or animals in how they reproduce and grow. The "seeds," called spores, are spread by the wind outdoors and by air indoors. Some spores are released in dry, windy weather. Others are released with the fog or dew when humidity is high. Inhaling the spores causes allergic reactions in some people. Allergic symptoms from fungus spores are most common from July to late summer. But with fungi growing in so many places, allergic reactions can occur year round... read more

Health Risks from "Toxic" Mold

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According to a 1999 Mayo Clinic Study, nearly all chronic sinus infections (afflicting 37 million Americans) are a result of molds.

A 300% increase in the asthma rate over the past 20 years has been linked to molds. (according to 1999 USA Today Cover Story)

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Molds (sometimes referred to as black molds, even though mold can come in a variety of colors) can cause a wide array of adverse responses in humans depending on the type and quantity that is present. However, these are not the lone factors when considering the health affects to mold exposure. Since dose and human response can be highly individualistic, the sensitivity of the person exposed is also an important consideration. For example, infants and young children, the immune-compromised, and the elderly are at an increased risk of experiencing adverse health effects related to mold exposure.

There are many routes of exposure to molds including dermal contact, ingestion, and inhalation. The health risks associated with mold exposure include, but are not limited to: allergic reactions, irritation associated with volatile organic compounds (VOCs), invasive disease, mycotoxicosis.

Allergy

Allergic reactions are elicited when a substance such as mold that is not harmful in itself causes an immune response in susceptible individuals. The most common symptoms of an allergic response to increased levels of mold range from runny noses, itchy-watery eyes, coughing, sneezing, and throat irritation to more severe symptoms caused by chronic conditions such as sinusitis and asthma.

Irritation

Fungi produce Volatile Organic Compounds during the process of degrading substances to obtain nutrition. The VOCs are the cause of the typical “moldy/musty” commonly associated with fungal contamination indoors. Exposure to high levels of VOCs may irritate the mucous membranes and the central nervous system leading to symptoms of headaches, decreased attention span, difficulty in concentration, and dizziness.

Invasive Disease

This type of disease is uncommon. It is an opportunistic infection caused by exposure to microorganisms that don’t normally produce disease in healthy individuals, but affects those persons with abnormally functioning immune systems. For example, those with HIV/AIDS or those receiving immunosuppressive drugs such as transplant or chemotherapy patients. Some common fungi that have been associated with invasive disease are Aspergillus, Cladosporium, Mucor, and Rhizopus.

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Air Purification to Reduce Amount of Spores Inhaled:

You may want to use an air purifier to minimize the airborne particulate, which allows mold spores to disperse to other areas of the home/house or building.

HEPA air filters are the most effective type of filter at capturing allergens such as mold spores. The Surround Air Multi-Tech air purifier uses a HEPA, in addition to a germicidal UV to destroy harmful mycotoxins created by mold.

FEMA MOLD REMEDIATION FACTS

Extensive disaster-related damages may result in public facilities becoming inundated or exposed to wet and humid weather conditions for extended periods of time. The limited availability of repair and restoration contractors may delay clean-up activities. In addition, the disruption of electrical power can inhibit the use of water extraction, pumping and drying electric equipment. As such, the damaged structures and their contents may remain waterlogged until power is restored and remediation can begin. Such water saturation may cause growth and propagation of mold on structures and interior contents, causing health-related problems and increasing the cost of repairs. The following guidance is provided to assist Public Assistance staff and applicants (entities that meet the requirements of 44 CFR 206.222 - State, local governments, Indian tribes or authorized tribal organizations, and certain private non-profits) with the remediation and/or repair of their damaged facilities... read more

Killing Toxic Black Mold - How to Remove Mold Safely

Killing Toxic Black Mold - How to Remove Mold Safely - Video

How do I get rid of mold?

It is impossible to get rid of all mold and mold spores indoors; some mold spores will be found floating through the air and in house dust. The mold spores will not grow if moisture is not present... read more