Fungi (mould) are present almost everywhere. In an indoor environment hundreds of different kinds of mould are able to grow wherever there is moisture and an organic substrate (food source). They can grow on building and other materials, including: the paper on gypsum wallboards; ceiling tiles; wood products; paint; wallpaper; carpeting; some furnishings; books/papers; clothes; and other fabrics.
Mould can also grow on moist, dirty surfaces such as concrete, fiberglass insulation, and ceramic tiles. It is neither possible nor warranted to eliminate the presence of all indoor fungal spores and fragments; however, mould growth indoors can and should be prevented and removed if present.
Mould on bathroom tile grout, in shower stalls, and on bathtubs is a common occurrence. Occupants can control this growth through frequent use of household cleaners. Water accumulation in indoor environments can lead to mould growth (and other environmental problems), which has been associated with human health effects. Indoor mould growth can be prevented or minimized, however, by actively maintaining, inspecting, and correcting buildings for moisture problems and immediately drying and managing waterdamaged materials. In the event that mould growth does occur, this guide is intended to assist those responsible for maintaining facilities in evaluating and correcting this problem.
Removing mould growth and correcting the underlying cause of water accumulation can help to reduce mould exposures and related health symptoms.Prompt remediation of mould-damaged materials and infrastructure repair should be the primary response to mould growth in buildings.
The simplest, most expedient remediation that properly and safely removes mould growth from buildings should be used. Extensive mould growth poses more difficult problems that should be addressed on a case-by-case basis in consultation with an appropriate building or environmental health professional such as an Occupational Hygienist. In all situations, the source of water must be identified and corrected or the mould growth will recur.
Effective communication with building occupants is an important component of all remedial efforts. Individuals who believe they have mold-related health problems should see their physicians. Individuals who may have an occupationally related illness should be referred to an occupational/environmental physician for evaluation, following any needed initial care.
The presence of mould growth, water damage, or musty odors should be addressed quickly. In all instances, any sources of water must be identified and corrected and the extent of water damage and any mould growth determined. Water-damaged materials should be removed or cleaned and dried. For additional information on cleaning water-damaged materials and personal belongings, contact 1300 138 366.
A trained building or environmental health professional may be helpful in assessing the extent of the moisture problem and mould growth and developing a site-specific work plan. The presence of a trained professional to provide oversight during remediation can also be helpful to ensure quality work and compliance with the work plan. A trained professional should have, at a minimum, a relevant science or engineering degree and two years of full-time supervised experience in mold assessment.
A visual inspection is the most important initial step in identifying a possible mould problem and in determining remedial strategies. The extent of any water damage and mould growth should be visually assessed and the affected building materials identified. A visual inspection should also include observations of hidden areas where damages may be present, such as crawl spaces, attics, and behind wallboards. Carpet backing and padding, wallpaper, moldings (e.g. baseboards), insulation and other materials that are suspected of hiding mould growth should also be assessed.
Ceiling tiles, paper-covered gypsum wallboards (Plasterboard), structural wood, and other cellulose containing surfaces should be given careful attention during a visual inspection. Ventilation systems should be visually checked for damp conditions and/or mould growth on system components such as filters, insulation, and coils/fins, as well as for overall cleanliness.
Equipment such as a Q-Trak or infrared camera (to detect moisture in building materials) or a borescope (to view spaces in ductwork or behind walls) may be helpful in identifying hidden sources of mold growth, the extent of water damage, and in determining if the water source is
Using personal protective equipment such as gloves and respiratory protection (e.g. disposable respirator) should be considered if assessment work might disturb mould. Efforts should also be made to minimize the generation and migration of any dust and mould.
Environmental sampling is usually necessary to proceed with remediation of visually identified mould growth or water-damaged materials. Decisions about appropriate remediation strategies are generally made on the basis of a thorough visual inspection and sampling. Environmental sampling is used to confirm the presence, type, and toxicity of visually identified mould.
If environmental samples are to be collected, a sampling plan should be developed that includes a clear purpose, sampling strategy, and addresses the interpretation of results. Many types of sampling can be performed (e.g. air, surface, dust, and bulk materials) on a variety of fungal components and metabolites, using diverse sampling methodologies. Sampling methods for fungi are not well standardized, however, and may yield highly variable results that can be difficult to interpret.
Environmental sampling should be conducted by an individual who is trained in the appropriate sampling methods and is aware of the limitations of the methods used. Using a laboratory that specializes in environmental mycology is also recommended. The laboratory should be NATA accredited in microbiology.
The goal of remediation is to remove or clean mould-damaged materials using work practices that protect occupants by controlling the dispersion of mould from the work area and protect remediation workers from exposures to mould. 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 mould remediation, OCTIEF have developed a standard set of guixdelines for remediation. 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 mould 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 mould 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
Relative humidity should generally be maintained at levels below 60% to inhibit mould growth. Short-term periods of higher humidity would not be expected to result in mould growth. 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.
For more information contact us on 1300 138 366 or visit www.octief.com.au