Stachybotrys Contamination

Generally, sampling for Stachybotrys involves a combination of surface sampling and air sampling. This is matched with a thorough visual inspection to search not only for mold but evidence of water intrusion as well. Many professionals start with bulk or swab samples, progress to cassette air samples, and follow with culture samples where the media has been selected based on the bulk or cassette sample results.

It is important to remember that air samples represent only a short window of time and that Stachybotrys spores do not become airborne as easily as other molds. Therefore the general consensus is that few, if any, such spores should be found in indoor air.

Samples should be collected by, or under the direction, knowledgeable professionals. Improper collection practices can endanger the individual conducting the sampling, spread the contamination, and lead to false results. Stachybotrys in particular is prone to wide variability in measured airborne levels.

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Risk Assessment

Providing general guidelines on interpreting medical tests or sample results is difficult due to the large variety of factors that influence Stachybotrys growth and spread, as well as the variability of symptoms between individuals. Because of its toxic potential most experts recommend that all Stachybotrys exposure be avoided by immuno-compromised individuals. This includes infants, individuals with significant lung disease, people undergoing chemotherapy or other cancer treatment, many of the elderly, and people who are HIV positive.

Whatever the health status or symptom level, exposure to suspected Stachybotrys should be minimized as much as possible. While certain situations do demand building evacuation pro rata corrective activities, oftentimes temporary solutions can be employed. When determining the best course of action in a Stachybotrys case the parties involved should consider the number of people involved, extent of the exposure, description of symptoms, sample results, history of the problem, location of the mold, type of activity in the building or area of contamination, type of air handling system, and public relations. In all situations the best information should be used to develop a plan of action that protects the building occupants without creating unnecessary panic until the mold, an underlying source of moisture is corrected. Interim plans to reduce immediate risk until permanent repairs can be made may involve:

• Isolation of the area or room where mold was found by shutting the door(s) and sealing around the jamb with painter’s tape.
• Isolation of supply the affected surfaces with plastic sheeting and tape.
• Isolation of supply and/or return air vents in the area where mold is present.
• Shut down of the heating, ventilation, and air conditioning (HVAC) equipment that serves the area impacted by Stachybotrys with necessary heating or cooling provided by alternate or temporary sources.
• Rearrangement of work/leisure activities away from the affected areas.
• Utilization of air cleaning devices that integrate high efficiency (HEPA) and activated charcoal filters.
• General cleaning using a vacuum with HEPA filtration.
• Installation of pleated filters on the heating or ventilation system
• Use of N-95 filtering face piece when disturbing any items in the area where mold is visible (see next section for information regarding precautions for actual mold cleanup).
• Temporary evacuation

The choice of any actions to deal with Stachybotrys on an interim basis should be made with the ultimate goal of mold cleanup also in mind so that duplicative or counterproductive actions can be avoided.

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Control of Stachybotrys Contamination

Currently no single set of regulations rules, or even industry guidelines exist which clearly defines mold remediation procedures. Nevertheless, there is considerable consensus in the healthcare community and restoration industry regarding the:

1. Importance of eliminating active mold growth inside buildings.
2. Necessity of using trained and experienced professionals for the remediation of extensive mold growth or mold contamination in high-risk situations such as hospitals, nursing homes, air-conditioning ductwork, etc.
3. Need for work practices that minimize the spread of contamination during the cleanup/ removal process.
4. Removal of porous building materials (ceiling tile, drywall, etc) that have been water saturated and now support mold growth.
5. Use of personal protective equipment by individuals conducting the cleaning or removal activities.
6. Isolation of the work area or removal of occupants while the remediation work is in progress.
7. Benefit of sophisticated engineering controls such as negative pressure enclosures, air filtering machines, isolated entry chambers, upgraded respiratory protection and the like of large scale mold remediation projects.
8. Importance of proper application of mold killing and mold removing cleaners (Calbrite).
9. Need for a complete cleaning of the work area so that it is visibly clean of all debris and dust.
10. Value of post-work visual inspection prior to the reinstallation of drywall or other finish components.

Despite this general consensus of idea, the specifics of implementation must be determined for each project. Before starting any mold control activity, particularly one that disturbs Stachybotrys, a number of important questions should be addressed:

1. Who will conduct the mold control project?
2. Are pre-work samples necessary?
3. What criteria will be used to determine a successful conclusion to the project?
4. What engineering controls will be employed?
5. What form of isolation, if any, will be used?
6. What cleaner will work effectively?
7. What materials are to be removed?
8. How is debris going to be packaged? Disposed?
9. What cleaning techniques will be employed? In what sequence?
10. What tools, supplies, and equipment are necessary?