Despite its common natural occurrence, the issue of mold is one which generates concern for a wide variety of people. Building occupants often believe mold can harm one’s health. Builders, property managers and others see mold as a significant source of liability. For insurers, payouts for mold claims have been a very significant problem.
This problem is compounded by the unpredictability of why and how mold appears in buildings, conflicting scientific evidence about health effects related to mold, and the confusing nature of the qualifications and competency of professionals who perform mold related services.
What we call “mold” is actually just the visible growth of simple fungal organisms. Structurally, molds are not much different from the mushrooms typically found in the grocery store. Each consists of two structural components: mycelium and spores. Mycelium is the actively growing part of the fungus, and is typically white or grey and very fragile. It is composed of approximately 90% water, is heavy, and does not become airborne easily unless dehydrated. Mushrooms are composed primarily of compressed mycelium. When we observe mold growth in buildings, though, it is typically masses of spores that are visible. Spores come in a wide range of colors from white to black and every color in between. They are extremely small and rapidly can become airborne. Spores function as the “seeds” of fungi. A single large mushroom can contain 2-4 million spores. Basically, fungal mycelium and spores are everywhere and make up a large part of the soil as well as natural airborne particulate matter. Some studies have shown that a gram of typical garden soil commonly will contain over 300,000 fungal cells. Fungi are extremely important to the ecosystem, as they rot plant materials back into nutrients which provide fertile soil. Bacteria provide the same function on animal-based materials.
Mold in Buildings
Given the amount of plant-based materials used in building construction, it is easy to understand the susceptibility of buildings to fungal growth. Wood, paper products, carpeting, drywall, glues and bonding agents, and many other organic materials used in construction provide a food source for fungi. Given the natural abundance of fungal spores and food sources in buildings, the only realistic way to prevent mold growth is to control moisture. At normal moisture levels, spores cannot germinate and give rise to colonies. However, when moisture intrusions occur in buildings, mold colonies rapidly can appear. Actively growing mold is very sensitive to drying and will die rapidly once materials are dried. However, spores can be produced in very large quantities and will remain long after moisture conditions have been corrected. Spores are extremely resistant to drying and can remain viable for many years under dry conditions. In buildings, dried spores are likely to become airborne and present inhalation risks for building occupants.
Mold Professionals and Services
In water intrusion or mold claims, the adjuster is faced with the daunting task of selecting or approving competent professionals to eliminate the mold or moisture problems and restore building conditions to normal.
Mold services are roughly placed into two categories—assessment and remediation. Assessment involves collecting data to evaluate biological and structural conditions in buildings. Remediation involves removing damaged or contaminated material, and sometimes includes reconstruction as well.
Like oil and water, these two services do not mix. In 2007, the State of Florida passed legislation which will license mold professionals as well as home inspectors. As specified in this legislation, the performance of both services on the same project will constitute a criminal offense. Repeated offenses will be punishable as a felony. This legislation will not be enacted until 2010, however. (We’ll take a closer look at this and other legislation in Part 2 of this article in the Fall 2008 issue.)
The conflict of interests which exists between assessment and remediation is universally recognized within the industry and is often cited in written references. While not regulatory in nature, the mold industry has widely adopted a set of guidelines published by the International Institute of Cleaning and Restoration Contractors (IICRC) known as the IICRC S520 Mold Remediation Specification. This document specifically, and in multiple references, states that the performance of assessment and remediation services constitutes a conflict of interests. Despite being well established as a severe conflict, some contractors still engage in both services and likely will continue to do so until it becomes a criminal offense in 2010.
Assessment is the process of determining biological or structural conditions within buildings. The outcome of assessment is often a set of remediation specifications used to restore buildings to original, habitable conditions. Assessment can be divided roughly into two distinct services: building diagnostics and biological assessment.
Building diagnostics is the evaluation of physical conditions in buildings, often in response to a moisture intrusion or mold outbreak. This process consists of collection of measured data or visual observations to determine the cause of existing problems. In cases of mold outbreaks, building diagnostics typically include a moisture assessment to evaluate current moisture conditions, as well as a detailed investigation to determine the source of the moisture intrusion if it is not readily evident.
Visual observations are used on the interior and exterior of buildings to identify structural conditions conducive to water intrusion and biological growth. Exterior suspect areas such as windows and doors, roofing, evidence of standing water against walls, improperly set sprinklers, and protrusions in the building envelope are evaluated. Interior suspect areas include A/C systems, plumbing fixtures and areas suspect for condensation.
Moisture screening can be performed by spot checking small areas with moisture meters, or by screening large areas with thermal infrared imaging cameras. Moisture meters are small devices which are placed in direct contact with surfaces. Wet surfaces will register on the meter, and will lead the technician to narrow in on the source of the moisture and provide an estimate of the level of moisture intrusion. The weakness of this procedure is that the meter only assesses small areas and must be in direct contact. To completely assess even a small structure is a daunting and impractical task.
Thermal infrared imaging is an amazing technology which uses a video camera sensitive only to infrared light. Surfaces of differing temperatures clearly show up in the camera as contrasting colors or shades. Wet surfaces have different temperatures than dry ones and can be clearly distinguished in the camera. Large areas can be scanned rapidly and direct contact is not required. Although very expensive, many professionals have purchased infrared cameras and undergone extensive training to use them properly.
Many other procedures such as long term humidity measurements, assessments of exterior coatings, and roofing analysis also are employed. Numerous stress tests can be employed as well. These involve using calibrated spray racks to apply water to building exteriors, then observing the effects from the interior. The American Society for Testing Materials (ASTM) has many standardized procedures for these evaluations.
In selecting a professional to provide building diagnostics, the adjuster must balance the expertise needed and the available budget. Many people provide building diagnostics. They range from building trades people and contractors, to structural engineers and home inspectors, to environmental scientists. Highly technical structural experts, such as structural engineers, may possess the highest level of competency and thoroughness for building evaluations, but also may have a commensurate price. For obvious problems, such as a leaking A/C drain pan, an engineering firm may be overkill. Frequently, a generalized inspection from non-engineers may result in a recommendation for a detailed inspection by a structural engineer when obvious causes of problems do not exist. Environmental scientists such as chemists and microbiologists often perform building diagnostics, but their most technical areas of expertise lie elsewhere.
This involves collecting and interpreting data relating to biological conditions in buildings. Biological assessment frequently includes sampling, which is the process of collecting materials from buildings for analysis by a testing laboratory. The most commonly employed procedures are air and surface sampling. In air sampling, a vacuum pump pulls a known volume of air through a small device which traps airborne particulate matter. The device is forwarded to a testing lab for identification and/or quantification of biological organisms present. Surface sampling utilizes swabs, clear tape, or other devices to directly lift biological particles from surfaces. After analysis, the laboratory forwards a report to the client with the results. The meaning of the lab results should be summarized by the technician, but results frequently are not interpreted at all. This occurs when those performing biological assessment lack educational background or knowledge about biological organisms. Some labs will provide limited conclusions based upon the results. However, no one from the lab is ever present at the property, so site-specific conclusions cannot be made.
In selecting a contractor to perform biological testing, the adjuster should consider the educational background, general knowledge, and experience of the contractor. Many building contractors and home inspectors have included biological testing in their services. As with building diagnostics, the expertise of the biological contractor may be reflected in the fees. People with a significant academic background in biology, microbiology, chemistry, or other technical disciplines may be the most qualified to perform the sampling and interpret the laboratory results in a meaningful and site-specific manner. Professionals with scientific expertise also may possess the greatest credentials when legal disputes or contentious issues arise and mold reports undergo intense scrutiny.
One of the most confusing areas related to contractor competence is certification. Numerous certifying organizations and certifications have been created in recent years. In Florida, no certifying organizations or certifications related to mold have regulatory or law enforcement authority. None of the certifications are licenses, nor are they issued by governmental authorities. Some other states have mold licensing and regulation in place, but Florida’s new mold law will not be enacted until 2010. Until that time, the mold industry in Florida will remain completely unregulated.
Some mold certifications are deliberately misleading. In one case, a company will print a mold certification for nothing more than payment of a fee. Other certifications are the result of short courses often lasting only one day and requiring no educational prerequisites. Some certifications require more rigorous prerequisites.
To better determine the qualifications and experience of a mold contractor, it is strongly recommended that a resumé, CV, or other evidence of actual qualifications and academic background be obtained prior to hiring. The reality of one’s qualifications becomes readily apparent through this process.
In part 2 of this article, we will discuss remediation, health effects and legislation related to mold services.
is a microbiologist and owner of International Microbiology and Mold Group
in Palmetto, FL. He can be contacted at email@example.com