Mold Remediation Guide: Mold Is a Real Threat
Introduction: Mold Is a Real Threat
As a mold remediation professional, you know mold is more prevalent than the average person might realize. Although exposure to certain types of mold is harmless in small doses, large mold colonies that develop in moist, low-airflow areas can cause serious harm to anyone who occupies a building with mold.
This fungal life form grows in multicellular structures called hyphae. Hyphae have a thread-like shape and can be used to differentiate mold from single-cell fungi, which are called yeasts. When mold spreads into groups of multiple hyphae, it is called a colony.
Mold emits small airborne elements called spores as a means of reproduction. Trace amounts of mold spores are nearly always in the air you breathe outdoors, but in an enclosed environment like a building, the presence of large mold colonies can create high concentrations of mold spores that will eventually make their way into the respiratory tract of nearby humans.
The potential severity of a mold infestation is what makes the removal process so crucial. In this guide, we’ll discuss best practices for the mold remediation process — and the entire industry as a whole — you should follow to maintain your status as a trusted, knowledgeable professional.
Health Effects of Toxic Mold
Exposure to spores can have moderate to serious health effects on people. These effects are magnified for immune-compromised individuals and can include respiratory agitation, respiratory infection, allergic reactions, rash, cold-flu type symptoms and in extreme cases even death.
The spores that molds emit contain natural poisons called mycotoxins. These toxins disrupt human cellular structures and processes — for example, protein synthesis, DNA and RNA synthesis. In more severe cases, neural effects have been reported, which include degradation of eyesight and color differentiation, deterioration of the visual field and reduced cognitive function.
In 1999, a Mayo Clinic study concluded that most chronic sinus infections were caused by exposure to fungal irritants. At the time, it was estimated that such infections affected 37 million Americans every year.
Of the more than 21 million Americans living with asthma, approximately 4.6 million — nearly a quarter of all those affected — are believed to suffer from the condition because of exposure to mold. While this study was focused on fungus exposure in homes, rather than commercial buildings, the estimated cost of medical expenses incurred due to these cases was $3.5 million.
Sick building syndrome or SBS is a term that is commonly used to describe general illness in workers in a space that is believed to be contaminated. It is specifically used to describe a situation where the time a given employee spends in the area shows a correlation with their health condition.
Mold in Residential Settings
When purchasing a home, the last thing a buyer wants to encounter during the inspection is mold. However, it’s a prevalent issue that many homeowners face. In homes with mold, the infestation is usually in basements and other areas with high condensation and minimal airflow. These types of areas need to be checked when debating on purchasing a property.
Even if the home doesn’t appear to have mold currently, it is important to know if any mold remediation work has been done on the property in the past. If so it should be clarified when, where and why the mold appeared.
Even with these precautions during the buying process, many homeowners will discover mold down the road and find themselves in need of remediation services.
Mold in Commercial Settings
Anytime commercial real estate is purchased, it is important to check when the space was last inspected for mold, and what, if any, mold remediation work was performed. When checking the property, buyers should look for areas with little airflow and high condensation. Mold will tend to grow where there are pockets of stagnant water or humidity.
While the federal government has no established standard for mold remediation, states with humid climates such as California, Texas, Maryland and Indiana have set up standards for the presence of mold spores in building airflow. The state mandates mold restoration in situations where this limit is exceeded, and failure to comply could result in eviction from the building.
Even in a state without mold laws, allowing a known toxic substance to grow on a property while the public is using it is a violation of habitability standards established in most property-use contracts. No business owner is going to rent a space if they know it contains toxic mold.
Many commercial property owners will require mold remediation services to keep their property habitable and help it to hold its value.
Correcting a Mold Problem
Mold can, and does, develop in places many might not think to look, which is why it’s important that property owners inspect a building on a regular basis. Unvisited maintenance rooms, damp stairwells or HVAC ducting where water pools are some examples. If a mold problem has taken foot, the mold removal process is straightforward, but it requires diligence.
In this guide, we’ll explore the most important things to know when combatting toxic mold in a commercial space, such as:
- How to recognize and assess a mold breakout
- The mold remediation process
- The equipment you’ll need to remedy it
- How to put a mold remediation plan into action
- How to ensure the problem doesn’t come back
There are hundreds of different types of mold, but the toxic varieties that can cause issues in buildings and homes typically fall into a relatively small group. We’ll start by looking at the most common toxic mold types and what’s involved in an initial mold evaluation.
Read on below or download the PDF version.
If you have questions concerning what’s in this guide or would like to inquire about buying mold remediation equipment, please contact us or call (855) 345-3555 to talk with an Aer Industries expert.
Table of Contents
Chapter 1: Evaluating Mold Problems/Pretesting
Nearly any building material can become a host for mold growth. Areas most commonly affected by mold will always be those with high moisture and humidity levels.
This explains in part how mold colonies develop without property owners knowing. Utility closets, stairwells or HVAC rooms located close to working areas can become infected, and the spores released by the resulting mold will travel into the work area of personnel located nearby.
Mold is attracted to softer, more porous materials like wallpaper, wet sheetrock, and wood. However, if enough moisture is present, colonies can grow on harder, less porous surfaces including concrete. Air conditioning and heating insulation that absorbs high levels of moisture due to its location is a prime home for mold colonies and should be disposed of and replaced if mold is discovered.
Soft rubbers and plastics used to seal windows can also serve as a home for colonies, which can spread to window glass with the right conditions.
How Severe Is Your Mold Problem?
Finding mold growth in a building is never a good thing. Let’s look at some cases where mold-testing equipment was used to determine the presence of mold and explore the steps taken to remove it.
At any time, it’s likely there is some form of mold growth in a given building, particularly if it’s located in a humid climate. If colonies cover less than about 10 square feet, or a 3 ft. by 3 ft. area, it may be easier to eradicate it. Mold growth of any kind, though, even if it is only covering a small space, should be treated right away (read about how to stop mold growth here).
Mold Evaluation Standards
If workers are complaining of excessive allergies or exhibiting more severe symptoms of potential mycotoxin exposure, it’s time to bring in mold testing equipment and evaluate the area.
The American Industrial Hygiene Association (AIHA) and American Conference of Governmental Industrial Hygienists (ACGIH) have established standards that should always be followed when testing for mold. The AIHA’s document “Recognition, Evaluation and Control of Indoor Air Mold” is considered the gold standard for adequate mold evaluation, and any professional performing mold remediation should be sure to follow the guidelines outlined in this document.
In “Designing an Effective Mold Sampling Strategy” the AIHA outlines the suggested experiment design to determine whether remediation is needed in a building. While mold spores are always present in outdoor air, the ACGIH stated in 1987 that when spore concentrations inside of a workspace exceed 1/3 the outdoor level, remediation action is necessary.
Different types of mold can be toxic at different levels of spore concentration. This is because of variables like spore size and toxicity.
A building is generally considered contaminated if spore presence in indoor air exceeds 10,000 spores per cubic meter (SPM) of air. The National Allergy Bureau holds that average outdoor counts of airborne spores typically range from 0 to 6,499 SPM. A concentration of over 50,000 is considered very high and will incite symptoms in nearly any human who exhibits mold sensitivity.
When measuring mold saturation using solid samples, rather than using mold air sampling equipment, the quantitative unit of measure is colony-forming units per gram (CFU). Note that air sampling is considered to be a more accurate method of testing because mold exposure on a particular surface might skew test results when performing this type of screening. Often, it is recommended to use air sampling in addition to testing specific surfaces.
Standards for CFU concentration categorize areas that produce fewer than 10,000 CFUs as low contamination. Areas of 10,000 to 100,000 CFU are medium, and areas of greater than 100,000 CFU concentration are considered highly contaminated.
Using Mold Testing Equipment
While not post-testing after mold remediation is almost never an option, there is some debate as to whether pre-testing is necessary. Of course, after the job is done it’s essential to do a thorough check to ensure the mold infestation has been completely taken care of. But if mold is obviously present in property, why conduct a pre-test?
With consideration to mold remediation professionals, pre-testing should never be optional, especially in certain situations. If failure to conduct a pre-test resulted in negative consequences, the remediation company would take most of the fall, as it would be a huge liability issue. Pre-testing also allows you to see exactly how bad the problem is in an outside professional’s opinion. Knowing the severity of the mold will provide you with a better roadmap for the necessary remediation steps you’ll need to take for your client.
Scenarios when pre-testing should never be optional include:
If there are medical conditions about an occupant of the building that could make them more susceptible to having a negative reaction to mold exposure.
If there is the potential that other rooms within a building could also have mold, it’s a good idea to test those other areas in the property, as cross-contamination could affect the amount of work that needs to be done.
If you can’t see the mold and need to verify that it’s there and determine a cause, pre-testing will help you decide on a remediation plan.
If the client, insurance carrier, testing company or remediator requests pre-testing.
If the parties involved don’t agree about how they want to proceed with remediation, pre-testing can prepare an accurate picture of what should be done.
There are many reasons to get an assessor’s mold report from a third-party tester and assessor for both pre- and post-testing. The biggest one is that as a certified mold inspector, it would be a conflict of interest to perform the analysis yourself — you shouldn’t have any influence on the results of your work or collected samples. Whether the property owner has the testing done separately, or you do your own sampling and send it out for testing, this is an important step to maintaining a trusted reputation as mold remediation professional.
When choosing a laboratory, make sure to use one that’s accredited by the American Industrial Hygiene Association. Other factors to consider include convenience, cost and turn-around time. Most inspectors pass their lab costs on to the customer, and your customers will notice if you aim to give them the best deal. As a mold remediation professional, it would be beneficial for you to refer to and stay updated on AIHA and ACGIH standards for specific methods for sampling and assess testing labs accordingly.
Mycotoxin in Mold
Testing mold properly is crucial because it allows us to identify any toxins growing in the specific types of fungus and respond accordingly.
Mycotoxin is the common denominator between all toxic mold varieties. Fungi and specifically the mold variants mentioned in this chapter produce mycotoxins as colonies increase in size, with larger colonies of mold generating significantly higher levels of mycotoxin.
Health effects caused by exposure to mold spores are the direct result of mycotoxin exposure. This type of toxin resists decomposition and is unlikely to be broken down by the human digestive system. An individual’s age, health, genetics, and other factors will determine how sick exposure to mycotoxins will make them.
High levels of exposure can cause mycotoxicosis, a condition characterized by the toxin hindering the body’s internal processes. Mycotoxins can stunt macrophage activities and inhibit protein synthesis, which explains the lung damage often seen in individuals who work around large mold colonies. Symptoms of mycotoxin exposure can be both acute and chronic.
Categories of Toxic Mold
Toxic mold species can be broken into five categories for legal purposes, Stachybotrys, Aspergillus, Cladosporium, Penicillium, and Fusarium. Within these categories exist hundreds of additional sub-species of mold, and there are many other mold species that are not classified as toxic, but they can cause considerable damage to your building, and maybe even allergic reactions.
Each of these varieties displays different characteristics that allow you to recognize them, and some types of infestation are more dangerous than others:
Stachybotrys Chartarum, also known as black mold, is a greenish-black mold that is frequently associated with “sick” buildings. While there is some argument over whether this mold is responsible for high-profile pulmonary hemorrhage cases in infants and its overall effects on humans, it is a definite mycotoxin producer and should be treated as very harmful if spotted in a building.
Researchers identify this mold by its ridged structure. While it initially spreads through a slime droplet, when the mold colony dries out, it can become airborne. This creates a high risk of exposure for people working close by a colony of S. Chartarum.
Both commercial and residential properties run a high risk of developing Stachybotrys infestations because of this mold’s attraction to construction materials. Stachybotrys is often introduced to buildings through groundwater exposure when a layer of dirt is left on drywall. This mold grows well on gypsum wallboard and cellulose materials such as wallpaper. It has also been shown to inhabit natural-fiber carpet, paper pipe insulation, wood, and wood products.
Stachybotrys can spread through the HVAC system in a building if it dries out, giving it the potential to spread rapidly.
This type of mold has been shown to cause dermatitis in animals and painful lesions in workers who handled straw where the mold was growing. It has also been associated with inflammation of mucus membranes, fever, cough, bloody rhinitis, headache, and fatigue.
A Stachybotrys infestation should be handled as a serious health issue and treated by mold remediation professional with the proper safety equipment. Building materials infected with the mold will need to be removed from the premises, and airflow to and from the area will need to be carefully managed.
Aspergillus mold grows in several different varieties, including Aspergillus Flavus, Aspergillus Clavatus, and Aspergillus Parisiticus. The most dangerous Aspergillus variant, Aspergillus Fumigatus, can have life-threatening effects.
Like Stachybotrys, Aspergillus is happy to take root in numerous common building materials and can become a problem especially during a hospital renovation or construction. It has been known to grow in sheetrock, specifically where walls are damp, and in cellulose materials like wallpaper.
Aspergillus can be recognized by its semi-transparent grayish color. It grows in different circular colonies and lacks the texture and sheen of Stachybotrys.
It can also consume carpet and acrylic paint. It can grow on UFFI, leather and HVAC insulation or filter material, and even such mundane materials as bird droppings, potted plant soil, plastic, and rotting wood.
It is easy to understand how a mold with such a broad appetite can pose a threat in many different settings. In addition to building materials, the mold’s bio-deteriorating qualities can lead to food spoiling, and people should never risk consuming foods that might be contaminated with this mold.
The most serious form of Aspergillus is Invasive Aspergilloses. If you have an allergy to Aspergillosis, specifically allergic bronchopulmonary aspergillosis (ABPA), the allergy isn’t usually life-threatening. However, Aspergilloses can be life-threatening to those with compromised immune systems.
Aspergilloses cause ear, nose and lung damage. The most severe effects are due to the deterioration of the respiratory system, which can lead to bleeding in the lungs. Remediation of an Aspergillus outbreak will require the use of dedicated mold remediation equipment and should be overseen by a professional.
Exposure to this strain of mold might make you uncomfortable, but Cladosporium isn’t potentially deadly like some of its relatives.
You’re more likely to smell this mold before you see it, but when colonies do become visible, they can appear as green, brown or black spots. Visible colonies are usually only seen in areas of high moisture. Cladosporium is one of the most common mold varieties, and all of them have similar effects to air quality.
Thankfully, most of the effects caused by Cladosporium infestation can be treated by over-the-counter drugs. Those who suffer reactions, should, of course, steer clear, but even though this mold doesn’t pose the threat some other strains do, its habit of colonizing an area after another mold is already present should be an indicator that it’s time for an inspection.
Molds that Cladosporium often follow include Penicillium, Aspergillus Versicolor, and Wallemia Sebi. All three of these are mycotoxin producers and should be handled with care.
Exposure to high concentrations of Cladosporium can cause an allergic reaction, and this mold is well known for triggering asthma attacks. Difficulty breathing and tightness in the chest are other symptoms of the small spores released by this mold, which can make their way into the lungs of nearby humans.
Cladosporium is commonly found growing on moist materials like wet insulation, food, damp painted walls, and even dead plants.
If the name looks slightly familiar to you, that’s because this mold is directly responsible for the wonder-drug Penicillin. First discovered in 1928 by doctor Alexander Fleming, the drug was a revolutionary step forward in the fight against bacterial infections.
Penicillium mold, however, doesn’t carry the same infection-treating powers as the medicine derived from it. Some Penicillium varieties are mycotoxin producers and can trigger allergic reactions in people sensitive to mold. Different strains exist that consume citrus, apples and other fruit, making this mold the most common cause of fruit spoilage. It has been known to colonize on leather objects as well.
There are more than 300 known species within the Penicillium genus, and depending on the species and length of exposure, it can have severe effects on humans. While the primary form of exposure for many people affected by Penicillium is through consumption of spoiled food, this mold can also release airborne spores.
Of the Penicillium varieties that can grow indoors and become airborne, several produce mycotoxins that can cause organ damage. When people are exposed to these toxins in large quantities, the results can be kidney and gastrointestinal damage, even lesions, distension and hemorrhage. A small number of Penicillium species can produce neurotoxins.
Bright colors differentiate Penicillium from other mold strains. It is easy to recognize as colonies usually appear yellow or blue-green.