Concern about indoor exposure to Mold has been increasing as the public becomes aware that exposure to Mold can cause a variety of health effects and symptoms, including allergic reactions. Bonsai has guidelines for the remediation/cleanup of Mold and moisture problems in commercial, government and residential facilities. Bonsai procedures are designed to protect the health of building occupants and remediators.

Mold can be found almost anywhere; it can grow on virtually any organic substance, as long as moisture and oxygen are present. There is Mold that can grow on wood, paper, carpet, foods, and insulation. When excessive moisture accumulates in buildings or on building materials, Mold growth will often occur, particularly if the moisture problem remains undiscovered or unaddressed. It is impossible to eliminate all Mold and Mold spores in the indoor environment. However, Mold growth can be controlled indoors by controlling moisture indoors.

Since Mold requires water to grow, it is important to prevent moisture problems in buildings. Moisture problems can have many causes, including uncontrolled humidity. Some moisture problems in buildings have been linked to changes in building construction practices. Some of these changes have resulted in buildings that are tightly sealed, but may lack adequate ventilation, potentially leading to moisture buildup. Building materials, such as drywall, may not allow moisture to escape easily. Moisture problems may include roof leaks, landscaping or gutters that direct water into or under the building, and unvented combustion appliances. Delayed maintenance or insufficient maintenance are also associated with moisture problems in schools and large buildings. Moisture problems in portable classrooms and other temporary structures have frequently been associated with Mold problems.

In some cases, indoor Mold growth may not be obvious. It is possible that Mold may be growing on hidden surfaces, such as the backside of dry wall, wallpaper, or paneling, the top of ceiling tiles, the underside of carpets and pads, etc. Possible locations of hidden Mold can include pipe chases and utility tunnels (with leaking or condensing pipes), walls behind furniture (where condensation forms), condensate drain pans inside air handling units, porous thermal or acoustic liners inside ductwork, or roof materials above ceiling tiles (due to roof leaks or insufficient insulation).

Some building materials, such as dry wall with vinyl wallpaper over it or wood paneling, may act as vapor barriers, trapping moisture underneath their surfaces and thereby providing a moist environment where Mold can grow. 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 building occupants are reporting health 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 from Mold growing on the underside of the paper. If you discover hidden Mold, call Bonsai for Mold remediation.

Mold Cleanup Methods

A variety of Mold cleanup methods are available for remediating damage to building materials and furnishings caused by moisture control problems and Mold growth. The specific method or group of methods used will depend on the type of material affected.

Wet vacuums are vacuum cleaners designed to collect water. They can be used to remove water from floors, carpets, and hard surfaces where water has accumulated. They should not be used to vacuum porous materials, such as gypsum board. They should be used only when materials are still wet—wet vacuums may spread spores if sufficient liquid is not present. The tanks, hoses, and attachments of these vacuums should be thoroughly cleaned and dried after use since Mold and Mold spores may stick to the surfaces.

Whether dead or alive, Mold is allergenic, and some Mold may be toxic. Mold can generally be removed from nonporous (hard) surfaces by wiping or scrubbing with water, or water and detergent. It is important to dry these surfaces quickly and thoroughly to discourage further Mold growth. Instructions for cleaning surfaces, as listed on product labels, should always be read and followed. Porous materials that are wet and have Mold growing on them may have to be discarded. Since Mold will infiltrate porous substances and grow on or fill in empty spaces or crevices, the Mold can be difficult or impossible to remove completely.

HEPA (High-Efficiency Particulate Air) vacuums are recommended for final cleanup of remediation areas after materials have been thoroughly dried and contaminated materials removed. HEPA vacuums are also recommended for cleanup of dust that may have settled on surfaces outside the remediation area. Care must be taken to assure that the filter is properly seated in the vacuum so that all the air must pass through the filter. When changing the vacuum filter, remediators should wear PPE to prevent exposure to the Mold that has been captured. The filter and contents of the HEPA vacuum must be disposed of in well-sealed plastic bags.

Remove Damaged Materials and Seal in Plastic Bags. Building materials and furnishings that are contaminated with Mold growth and are not salvageable should be double-bagged using 6-mil polyethylene sheeting. These materials can then usually be discarded as ordinary construction waste. It is important to package Mold contaminated materials in sealed bags before removal from the containment area to minimize the dispersion of Mold spores throughout the building. Large items that have heavy Mold growth should be covered with polyethylene sheeting and sealed with duct tape before they are removed from the containment area.