The answer is complicated only in that there are several correct ways to remove mold and you, as a property owner, always have a say in the means used when the public is not at risk. There are several private and governmental organizations that publish guidelines for mold removal. The most notable are the Environmental Protection Agency guidelines: A brief Guide to Mold, Moisture, and your Home and Mold Remediation in Schools and Commercial Buildings (EPA), the American Conference of Governmental Industrial Hygienists Bioaerosols Assessment and Control, (ACGIH), The New York City Department of Health's Guidelines on assessment and Remediation of Fungi in Indoor Environments (NYC Guidelines), the Institute of Inspection, Cleaning, and Restoration Certifications S-520 Standard and Reference Guide for Professional Mold Remediation(IICRC S-520), and our states own minimum standards: Texas Department of State Health Services, Texas Mold Assessment and Remediation Rules (TMARR). In short, there are many accepted means to remove mold--some better than others and some certainly better in specific situations. Bottom line-if you won't be performing the clean-up yourself, find a state licensed assessment consultant and remediator you trust and solicit their input before finalizing your decision.
When determining the best remedy for your mold issue you must first consider several issues to best determine the means of removal. Remember, all structures but the finest clean rooms have mold in limited quantities. It is only when quantities are abnormally elevated that mold removal is required.
- What measures are required to protect the workers?
- What controls are required to protect the occupants and, are any occupants in a high-risk group?
- Do the remediation operations have the potential to cause appreciable levels of mold to become airborne? If so, is this airborne mold a concern to the property or the occupants?
- Does the mold remediation need to be performed in a manner that minimizes disruption to your business or household activities? If so, are you willing to sacrifice complete isolation of the occupants and structure from the airborne mold if required?
- Will economics play a role in determining the means of removal?
- How likely is hidden mold to be found during the work outside the known established perimeters?
These and other questions are important to consider when making decisions related to mold clean-up.
When contemplating the various methods of mold removal you can generally classify the general modes into the following three groups yet the actual techniques specified often combine methods.
- Cleaning/Surface Agitation Abrasion
- Chemical Treatments and Encapsulants
When an object is contaminated by mold, it is not automatically destined for disposal. More often than not, non-porous items such as smooth glass, metal, plastic, finished wood, painted walls, etc. can be cleaned.
The decision to clean or replace non-porous items is more often financial than it is technical since they can almost always be cleaned (how much labor/cost to clean vs replace).
Porous items on the other hand present greater complexities regarding cleaning. Clothing and other fabrics, carpets, upholstered items, unfinished wood, insulations, unfinished or rough masonry, ceiling tiles, paper products, etc. are all more challenging to clean. It is a generally accepted practice to dispose of porous items of limited value when mold growth has occurred on the item in lieu of mold contamination simply being imposed on the item due to proximity. The decision to clean or replace porous items is first technical then financial since some of these items would require very expensive remediation to be returned to a state of usefulness.
Many of these porous items can actually be cleaned but the value of the item must be weighed against the cost and or time required to perform the cleaning task. Would it make sense to spend $10 cleaning 20 pieces of paper used as a note pad? Not likely! What if the papers were hundred dollar bills or priceless art? Your child's first report card? Your original diploma? A quilt left to you by a deceased loved one? An original legal document with irreversible impact on the outcome of a major case? These are the never-ending decisions required of persons or entities plagued by mold colonization or contamination.
When the decision to clean any item is made, it's then time to determine the best means of cleaning. At 877QuicDry (877-784-2379), we utilize several methods of cleaning.
- Air washing: High pressure dried air applied directly to the surface of the contaminated item.
- Abrasive blasting: Usually sand, soda, or dry ice particles introduced into an air stream and projected onto the surface of a contaminated item.
- HEPA (High efficiency particulate air (or arresting)) or remote vacuuming: vacuuming contaminated object and either capturing the mold particles or exhausting them in a remote safe area outdoors.
- Wet wiping: This involves simply wiping down and rinsing a contaminated item.
- Steam cleaning: Steam can be very useful in dislodging mold.
- Irrigation/Rinsing: Some easy-to-clean items can simply be rinsed off.
- Mechanical abrasive processes: This would include wire brushing, grinding, sanding, etc.
- Filtration: Most of the cleaning processes above are performed in conjunction with HEPA air filtration via the utilization of hepa air scrubbers.
Since cleaning alone introduces no added chemicals or other contaminants into the environment, it is favored over various treatments when viewed from a purely technical basis. The balance again is the intense labor costs associated with detailed cleaning vs simply performing a quick clean then applying a biocide and/or anti-microbial coating. We will discuss these two treatments in the following section.
The decision to perform detailed cleaning or treatment is one of the most crucial aspects of a mold remediation project. It involves both the quality of the work and the cost. This decision should be given diligent consideration and should not be made by either the mold assessment consultant or the mold remediation contractor without due input by the owner or other responsible party.
There is a gradual movement within the industry to push cleaning in lieu of treatment, where the structure is concerned. The reason is that the coating and treatments used can be as detrimental as the mold itself to persons with chemical sensitivities. Other concerns of treatment are whether they meet specific building criteria regarding flame spread, smoke development, and vapor transmission where applicable. In addition to the tasks of the remediator, the consultant must be capable of producing realistic clearance criteria (levels that will be considered acceptable upon final testing) for porous items and the adjacent air where applicable.
Cleaning a significantly contaminated structure to a level that will pass stringent clearance criteria without treatment is no easy task. The same is true of many special contents. Wood studs are very porous and are being recontaminated constantly by abrasive sanding and grinding. This is a point where the owner, consultant, and remediator should discuss the issue providing as much information as possible for the owner to ultimately lead the group in making that decision.
A $3000.00 mattress may be capable of being cleaned, but how clean is clean? A reliable method of testing is as complicated as setting the clearance criteria. Its our opinion that this confusion or lack of regimented standards is responsible millions of dollars in unnecessary disposal of mattresses, upholstered furniture, and other similar items but at the same time we entirely understand the complications and liabilities related to saving and cleaning them. Again, the owner should be educated and then lead the team in making the final decision. We have successfully cleaned and tested mattresses, carpets, and many other items previously slated for disposal. Always balance all the options and costs before making a final decision.
This process is as simple as the title suggests. After reviewing the other options of cleaning and treatment, disposal is often a cost effective alternative. You must weight the value of the product against the cost to remediate it. If a new room of nice carpet is worth $700.00 dollars and the cost to cover it and eventually remediate it is $400.00, the carpet is still worth saving. If that same room of carpet is eight years old and the useful life of the carpet is considered, the value may lie with replacement. To complicate issues even more, the expensive cost of large scale remediation can exhaust an owners funds. The decision may not lie totally in the value but also in available liquid resources or cash flow. Again, it is critical to allow the owner a major role in making these decisions. Too often, the owner is not adequately consulted.
Methods related to disposal fall into two general categories: Disposal in a contained setting and disposal in an open setting.
Disposal in a contained setting is performed by placing removed building components or contents into double sealed plastic bags which are ultimately wiped-down prior to being exposed to uncontaminated portions of the structure before being placed in a refuse container.
Disposal in an uncontained setting such as a structure that has been flooded and is contaminated in all areas can be performed very much like standard demolition except with added emphasis on environmental controls and personal protective equipment designed for worker safety. No special packaging or disposal in typically required in this scenario.
Mold requires no special disposal manifests or transportation packaging, and is subject to no special landfill regulations. In fact, it is actually crucial to the ultimate decomposition of landfill waste. Remember, mold is everywhere in our natural environment, especially in our landfills.
We discussed the pros and cons of treatments vs cleaning and disposal in the previous two sections so we will focus simply on the treatment types in this section.
It is important to note that all these products have the potential to be hazardous to the health of the person applying the treatment and other persons nearby. Proper PPE is always required during the application and immediately thereafter.
It is our opinion that no single product or combination of products exists that can effectively be applied to a mold contaminated structure that will address all concerns. There are products that can be applied to render the mold non-viable, to halt growth of active mold, and to inhibit mold growth in the future. None of these products remove the actual contamination and, where applicable, the associated toxins.
Ozone: There is ongoing discussion about the merits of ozone in mold remediation. We have extensively researched this topic and feel it is unsubstantiated. We do use ozone for odor remediation but even then in a very controlled fashion. Ozone is an irritant and threshold limits do exist for human exposure. It should be used cautiously.
These chemicals are often the consistency of water and are applied by a variety of methods including rag or sponge, pump-up sprayer, fogger, hand spray bottle, and more. Most require contact with the contaminated surface a minimum of one minute in liquid form which can require a substantial wetting for items like wood framing members. The primary argument against biocides is that they add unnecessary chemicals to the process. There is also a potentially valid concern that the actual spore is not always rendered non-viable through specified contact with the chemical since the spore is not in a state of germination. The argument for these chemicals is that it kills the majority of the mold and leaves the remnants unable to grow or reproduce.
Anti-microbial Sealants: These sealants do have useful applications in remediation. They are designed to not support mold growth on their surfaces. These sealants not only control mold growth but also perform a very cost controlling feature of encapsulating mold spores that could otherwise become airborne. This can be a considerable cost savings to the project. In that process the coating would also be acting as an encapsulant. If the moisture source is eliminated, the visible mold is removed, and a thorough anti-microbial sealant is applied, its hard to argue that the remaining encapsulated mold fragments, spores and associated toxins pose any appreciable risk to health or property.
We generally support the use of specific anti-microbial products but only to the extent that the owner or responsible person can be certain that persons exposed are not chemically sensitive and moisture trapping is not an issue, in which case we oppose its use.
Most will not argue the merits of anti-microbial sealants on mold removal projects but potential downsides are as follows:
Most persons specifying means and methods would prefer to not specify the addition of any unnecessary chemicals or chemical compounds.
Moisture migration issues:
Applications of anti-microbial coatings can impede moisture migration. Some marginal moisture issues never manifest into fungal problems because the evaporation of the moisture is equal to or greater the relating production. If a coating were applied to a component under this condition, that component has the potential to experience decay, corrosion, or other problems as a direct result of the application of the product. Manufacturers often attempt to design the products to allow for some moisture migration but even this is subject to exact application standards regulating mil thicknesses which are difficult and expensive to control and verify.
One example of this condition would be moisture migration through an older concrete slab without a vapor barrier. This home could have survived many years without decay of the untreated sill plate until a sealant is added. Of course the anti-microbial sealant has no mold on it but the sill plate could easily develop fungal decay within it due to increased moisture content of the wood caused by the coating's impedance of moisture out of the plate.
Flame spread and smoke development: All manufactured building components are subject to regulations which define flammability and smoke development under specific conditions. Each product added must conform to these regulations.