Because of the potential for health risks from mold, clean-up should be attempted only after it has been determined what type of mold is present. In addition, certain safety precautions need to be taken to ensure your health and reduce the likelihood of recurrence. If you are at high risk for illness from mold due to another factor, there are additional considerations.
Another issue for mold clean-up is how extensive the problem is that you are facing. If you are cleaning an area of approximately 10 sq. ft., it’s likely that you can handle the job effectively. However, larger areas are more problematic and should only be undertaken by professionals.
Some items may be damaged so badly that they must be thrown out and replaced. But, what about irreplaceable heirlooms and valuables? There are specialists in antique furniture repair and restoration, painting and art restoration and conservation, and tapestry cleaning. When contacting a company, be sure to ask about their process for mold clean-up, experience, and references. Also, because mold that is left to sit untreated has the potential to spread to other areas, be sure to ask how quickly they can begin. Ask if there are any steps you should, or shouldn’t, take before they can begin the job.
If you have any reason to suspect that the mold problem is occurring in your HVAC system, it’s best not to run the system until its checked by a professional. Running the system with mold inside could spread the mold spores throughout the building creating a larger problem.
InterNACHI (International Association of Certified Home Inspectors) wrote a guide addressed to home inspectors on air sampling due to mold.
Sampling, Site Visits, Interviews and Questionnaires
Determining the exact cause and extent of mold damage may be done by several different methods. Some or all of these may be used by the mold remediation expert. Both indoor and outdoor samples may be taken as controls. Higher mold levels indoors than outdoors is indicative of a mold problem.
Site Visit: It’s critical that your mold clean-up professional visit your property prior to making any judgments or estimates. This will allow him/her to assess the extent of the damage, the success of any repairs, and check for other contributing factors that may need to be resolved prior to clean-up beginning. In addition, visually inspecting the areas will give the technician an opportunity to view the visible mold and make a preliminary guess as to what type of mold is present.
If an inspector or expert is not confident in their health or safety in the visit, it may be postponed until protective gear is obtained. If the damage is too extreme and hazardous, the expert may decline to enter at all.
Interviews and Questionnaires
Depending on their sensitivity, people react to mold in different ways. And, some people may be more observant visually and in their sense of smell. By talking with various occupants it may help ensure that all areas where mold growth is occurring are inspected and treated if necessary.
In a home environment, talking with family members and making notes may be all that is required. However, in a business environment where there are many employees that may be impacted by the mold, the mold expert may ask that questionnaires be completed about what has been seen, smelled, or experienced by the occupants. By doing the questionnaires, it ensures that the occupants concerns are addressed fully to provide documentation for the company and the property owner.
Mold sampling may be done to determine if there are active mold spores and to help determine areas of high concentration. By taking samples, it can also be determined what types of mold are present. While actual mold growth can be seen, mold spores are not visible to the naked eye. There are several methods of taking samples:
- settled dust samples: collecting spores that have settled on a given area
- air samples: collecting samples that are airborne
- dustfall collector: collecting samples as the spores drift down through the air
- surface collection: scrapings of existing mold
Many sampling methods use a collection media so that the type of mold can be easily grown in the laboratory to determine the type/s.
Mold sampling can provide insight into a mold problem, but may not give you a complete picture. For example, by doing air and dustfall collections, the mold tester may get different results depending on the conditions at the time the sample is collected. Differences in time of day, temperature, location, relative humidity, and air flow can all impact what is collected. And, samples must be taken from several areas in order to be more accurate.
Air sampling is usually the preferred method of collection. Collections are often taken in the middle of living space at a height of 3′-6′ from the ground. Outside doors and windows will be kept closed to avoid outside contaminants or wind. Various methods may take different amounts of time. For the pump type of air collection, 5-10 minutes would be adequate to obtain a sample.
Surface samples of existing molds are easier to obtain with less variance in relation to the conditions under which they are taken. However, surface sampling may not give a complete picture of the types and level of mold spores in the air and only show what is currently on the surface. This can lead to an inaccurate picture of the problem that exists.
Sampling is only as good as the effort that is put into collection. If sampling is done only once, or only in certain areas of the building, that might not show all the mold spores that are present at other times and conditions.
If you choose to hire someone for clean-up, ensure that the company has the experience to do the job effectively and completely. Check for references and ensure that they do the clean-up in accordance with EPA guidelines.
- The process for professional clean-up will begin with your call to a mold remediation company. You will be asked a series of questions to aid them in determining the extent of the problem you are having and their course of action.
- The mold remediation expert will visit your site and do an inspection. In addition to taking note of visible molds, s/he will do an assessment for invisible molds. The company will also want to make sure that the problem that lead to the mold growth has been repaired or corrected.
- Barriers will be established, if possible, to prevent the spread of mold spores during clean-up. Barriers may be physical or may be air pressure to keep air from exiting an area or entering another area. HVAC systems and other fans will not be used during the clean-up period.
- Workers will use protective gear as needed to ensure their health and safety during the clean-up.
- Air filtration and purification systems, like cleaners with HEPA filters, will be used to remove the mold spores from the air. These will be used while the clean-up is in progress to ensure the spores don’t travel to other areas of the building.
- Cleaning will typically use antimicrobial and antifungal products to kill existing mold and reduce the likelihood of regrowth. While cleaning will be attempted to save property when possible, some materials or property may be damaged to the extent it must be destroyed. Drywall, wallpaper, insulation, and carpeting are examples of materials that may need to be destroyed. Cleaning of salvageable property will be done using various cleaning methods and odor removers.
- Restoration of areas that have been severely damaged may be undertaken by the same company, if employing professionals. Or, the work may be contracted to other building professionals. The extent of the work needed and cost will depend on the severity of the mold problem.
Follow-up Following Remediation
It’s wise to have sampling done following remediation to make sure the problem has resolved satisfactorily. It will never be possible to eliminate mold from the environment completely, but sampling can show a satisfactory decrease from previous levels and species.