Posts filed under ‘Indoor Air Quality’
Fungal Data Interpretation – Part II – Effects of Tossing a Moldy Apple Pie into the Trash Before Mold Air Sampling
This post is the second blog posting in a series based on information presented in a webinar by Dave Gallup, co-founder of EMLab P&K. The topic of the webinar was Fungal Data Interpretation. The two-hour presentation covered many interesting topics that are relevant to mold inspection and testing companies as well as the general public that are facing mold problems in their home or business.
One of the first points that Mr. Gallup made is the interpretation of the sample data that EMLab P&K provides must be combined with the on site mold inspection information. Trying to interpret fungal sample data from a mold inspection and testing project without also having field inspection information from a qualified mold inspector is highly problematic. In this blog entry I will focus on the second of several normal household scenarios that can drastically impact fungal sample data and could lead to incorrect interpretation of that data.
Scenario – “Effects of Tossing a Moldy Apple Pie into the Trash”
A group of EMLab P&K scientists studied the impact on fungal distribution in a normal home after the occupants tossed a mold apple pie into the kitchen trash. Here is the data set:
- The first air sample was collected in the home before tossing the moldy pie.
- The air sample contained numerous types of mold spores. I will focus on just one type, Penicillium/Aspergillus types (Pen/Asp).
- The spore counts of Pen/Asp found in this first air sample were within “normal tolerances” — they were lower than the corresponding spore counts found in the outdoor baseline sample.
- The second air sample was collected during the act of tossing the moldy pie
- The spore counts of Pen/Asp were significantly elevated compared to both the outdoor control sample and the first sample collected before the toss.
- This is how the data looked:
- Pen/Asp types: before tossing ~13 spores/cubic meter | during tossing ~ 1,000,000 spores/cubic meter!
If the on site inspector did not notice that there was moldy food in the trashcan (apple pie in this case) or had not asked the homeowner if they had recently performed any housekeeping activities such as cleaning out the refrigerator of moldy food, incorrect conclusions could have been made with respect to this project. For example the airborne Pen/Asp types prior to tossing were ~13 spores/cubic meter. After tossing the moldy pie into the trash, the spore counts of Pen/Asp were drastically elevated (over one million spores/cubic meter!). If the inspector did not know about the moldy food, these air sample results would be cause for real concern and unnecessary steps would likely follow (more testing, invasive exploration for mold, and the like). Armed with the knowledge that the client recently threw away moldy food, the inspector could either take that into consideration when analyzing the sample data or, better, not collect the sample for several hours after.
Many people place too much emphasis on the mold sampling aspect of our business. It is a useful tool, but it is only truly valuable in conjunction with the on site, visual inspection data.
The Basics of Mold Remediation – Part III of III – Final Cleaning of the Containment and Affected Areas
See my posts “The Basics of Mold Remediation – Part I of III – Containment of the Affected Area” as well as “The Basics of Mold Remediation – Part II of III – Gross Removal of Mold Growth and Impacted Materials” for background information important for understanding this part of the mold remediation process. At this point in our process, the mold impacted area has been isolated from all non-affected adjacent living spaces. This was accomplished by establishing containment of the area, which included the installation of HEPA Filtered Negative Air machines and installation of physical barriers which, in turn, would have created a negative pressure environment. Gross removal of all impacted non-structural materials would have occurred as well as the removal and cleaning of mold growth from all of the structural materials. The next step is to perform the final clean of the work area.
Part III of III – Final cleaning of the containment and affected areas.
Now that the nitty gritty portion of the removal has been accomplished, the work area has typically seen a fair share of debris. Not only does the removal of building materials create lots of dust and debris, but the disturbance and removal of the mold source itself typically creates very large quantities of microscopic mold spores. So, how do we make sure we account for all of those spores that we can’t even see with our naked eye? Well, the simple answer is by cleaning everything, and doing it very well. That means every crack, crevice, cavity, ceiling, wall, floor and the air itself must be cleaned.
The first step in the final cleaning is typically a complete HEPA vacuuming of the entire space. Every surface within the containment area will be HEPA vacuumed to gather any dust, debris, and yes, lots and lots of mold spores. The vacuums used are not the typical vacuum you can find at the hardware store, but specialized HEPA vacuums that prevent those microscopic spores that are being sucked up from being re-distributed throughout the space.
Once the area has been HEPA vacuumed, the remediation contractor will typically perform a wet wipe of the area at this time. They will use a cloth that is wetted with some sort of antimicrobial agent or cleaner, and every hard surface will be wiped down. The rags are kept wet not only to aid in the cleaning process, but to help in picking up mold spores and preventing them from becoming airborne.
At this point, some remediation contractors may choose to repeat the previous two steps, and HEPA vacuum the entire space as well as do another wet wipe to ensure that every surface has been accounted for. And after all, it’s better to be safe than to be sorry, or at least that’s what they say.
During all of the previous cleaning efforts, the HEPA filtered negative air machines have been running the entire time. As a result, airborne mold spores have been pulled out of the air and into the filtration device. As the cleaning has become more and more detailed, the airborne mold spore quantities should have been continually getting smaller. Unfortunately though, the quantities of airborne mold spores at this time will typically still be in excess of actual clearance standards. So, at this time the negative air machines are swapped out for HEPA filtered air scrubbers. Instead of air continually being drawn out of the space and as result unconditioned air being drawn into it, the air within the space will now be recycled through the HEPA filtered air scrubbers. As the air is continually pulled through the HEPA filters over and over again, it will become “cleaner” as more and more of those microscopic mold spores are trapped within the HEPA filter. This process is usually continued for a minimum of 24 hrs, and depending on the amount of contamination in the space may go on for multiple days.
At this point, the remediation project has come a long way. We have gone from a mold contaminated area, to what we hope is considered to be a “normal” living space. But, to truly verify whether the space has been returned to normal a Post Remediation Verification Inspection should be performed. This should be performed by an independent mold inspector who has no financial ties with the remediation contractor. They will perform a visual inspection of the space to ensure that all of the impacted materials have been removed and/or cleaned, test the moisture content of the building materials to ensure that everything has been adequately dried, and ensure that the area has been properly cleaned. If the visual inspection is adequate, then they will perform ambient air sampling of the work space. This will test for the presence, types and quantities of mold spores within the space and will be compared to an outdoor sample taken at the same place and time. If the sample is within clearance standards, the project will be considered successful, and the mold remediation project complete. All that is left at this point is reconstruction of the space to return it to a normal living space. After all that we have gone through, that should be a walk in the park…
Yesterday, I had the privilege of attending a webinar presented by Dave Gallup, co-founder of EMLab P&K. The topic of the webinar was Fungal Data Interpretation. The two-hour presentation covered many interesting topics that are relevant to mold inspection and testing companies as well as the general public that are facing mold problems in their home or business.
One of the first points that Mr. Gallup made is the interpretation of the sample data that EMLab P&K provides must be combined with the on site mold inspection information. Trying to interpret fungal sample data from a mold inspection and testing project without also having field inspection information from a qualified mold inspector is highly problematic. In this blog entry I will focus on the first of several normal household scenarios that can drastically impact fungal sample data and could lead to incorrect interpretation of that data.
Scenario – “Effects of Vacuuming”
A group of EMLab P&K scientists studied the impact on fungal distribution in a normal home after the occupants vacuumed their carpets. Here is the data set:
- The first air sample was collected in the home before vacuuming the carpet.
- The air sample contained numerous types of mold spores. I will focus on three types: Basidiospores, Cladosporium, and Penicillium/Aspergillus types.
- All of the spores counts found in this first air sample were within “normal tolerances” — they were all lower than the corresponding spore counts found in the outdoor baseline sample.
- The second air sample was collected during the act of vacuuming the carpet
- All of the spore counts were significantly elevated compared to both the outdoor control sample and the first sample collected before vacuuming.
- This is how the data looked:
- Basidiospores: before vacuuming ~70 spores/cubic meter | during vacuuming ~ 800 spores/cubic meter.
- Cladosporium: before vacuuming ~80 spores/cubic meter | during vacuuming ~ 1,000 spores/cubic meter.
- Penicillium/Aspergillus types: before vacuuming ~110 spores/cubic meter | during vacuuming ~ 1,100 spores/cubic meter.
- The third air sample was collected in the home 30 minutes after vacuuming.
- All of the spore counts were still elevated as compared to both the sample collected prior to vacuuming and the outdoor control sample, though not quite as high (about 50% as high as the during vacuuming sample) as the sample collected during vacuuming.
If the on site inspector did not notice that the carpet had been recently vacuumed (i.e. seeing the vacuum “tracks” in the carpet or notice the dusty smell or see the vacuum sitting out) or had not asked the homeowner if they had recently performed any housekeeping activities such as dusting or vacuuming, incorrect conclusions could have been made with respect to this project. For example the airborne Penicillium/Aspergillus types prior to vacuuming were ~80 spores/cubic meter. A half hour after vacuuming, they were ~500 spores/cubic meter which is approximately 6 times higher. In absence of the vacuuming, this could indicate a mold problem which would entail further investigation such as invasive investigation and could concern the homeowner. Armed with the knowledge that the client recently vacuumed, the inspector could either take that into consideration when analyzing the sample data or, better, not collect the sample for several hours after housekeeping activities.
Many people place too much emphasis on the mold sampling aspect of our business. It is a useful tool, but it is only truly valuable in conjunction with the on site, visual inspection data.
In my next posting related to Fungal Data Interpretation, we’ll see the impact on the airborne fungal distribution when a moldy apple pie is tossed into the trashcan!
Mold in attic areas can be challenging at times in regards to determining the exact cause and source of mold growth. However, there are some common conditions that we routinely find during our Mold Investigations that contribute to mold growth in attics.
Penetrations in roof systems are common sources of water intrusion into attic spaces. Improper flashing, deteriorated rubber boot flashing, missing or improperly installed flashing around chimneys or other penetration points, and inadequate roof repairs are common causes of roof leaks. Also, water seepage occurs when the roof is beyond the end of its life span and failing. Water damage and mold growth is a common result of roof leaking conditions. Annual inspection of your roof by a roofing specialist and routine maintenance can prevent leaks in the roof system, reducing the likelihood of mold growth in your attic.
Inadequate Roof Ventilation
The lack of proper roof ventilation is a conducive condition to mold growth in attics. Without adequate ventilation, moisture laden air remains in the attic area, often times causing elevated moisture conditions at the roof framing and roof sheathing. During cold winter months, condensation can occur on the cold roof sheathing, creating elevated moisture conditions.
Another common cause of inadequate ventilation is when insulation is blown into the attic and care is not taken to prevent the insulation from blocking the soffit vents. Soffit vents are critical in a passive ventilation system in order to move the air from the lower portion of the attic (intake soffit vents) to the upper roof vents (exhaust vents). Adding additional ventilation ports or a powered roof vent can oftentimes improve and correct inadequate roof ventilation conditions.
Bath & Kitchen Exhaust fans vented into the attic
Exhaust fans should be vented directly to the exterior of the home. However, this often is not the case. When the exhaust fan is missing its exhaust duct or the duct has become separated, that exhaust air is vented directly into the attic space, oftentimes contributing to microbial growth.
Missing or inadequate attic insulation
Attic insulation not only is important in energy conservation, but proper insulation levels can also reduce the chance of mold growth in attics. As air travels up through the structure, insulation provides a barrier to slow the rate of conditioned air loss into the attic area. When an attic has missing insulation, the air movement increases significantly and that warm air can cause condensation conditions on cold roof sheathing. The moisture conditions resulting from such condensation is a catalyst for mold growth. Check your insulation and make sure that you have good and even coverage throughout the entire attic, especially at the lower North side areas.
Gaps or openings in ceilings
Unsealed openings in ceilings, around exhaust fans, can lights, speakers, etc. allow warm conditioned air to escape into the attic area. Sealing all penetrations in the ceiling can be an important preventative step in reducing mold growth in attics.
Finally, we frequently get asked, why is mold in an attic a big deal? While it is true that attic areas are not generally considered living spaces and air communication from upper attic areas to the living space below is relatively uncommon (in most normal situations), attic mold should still be a concern. Why? Because it is possible that if negative pressure conditions exist or occur in the home, air containing mold spores could potentially be drawn from that attic area into the living space. In addition, attic mold is usually an indication of other defects or conditions that could lead to costly repairs down the road. Such as water damage, Mold contamination in the finished living areas, wood destroying organisms and other moisture related conditions. Now go check your attic and if you see unusual staining or mold-like conditions, call a mold professional for a full assessment and appropriate testing.
Part of a proper mold investigation, is collecting ambient air samples in relation to suspect conditions within a home. This helps us determine if there are “suspect” or “elevated” airborne mold spore types and/or concentrations. This not only helps us in determining if hidden mold sources are likely, it helps us determine the overall impact mold is having on the environment and in turn allows us to give proper recommendations for remediation (the removal of mold).
To properly asses the indoor conditions, we must first collect an outside control, or baseline sample. This is necessary because we always have to remember that airborne mold spores are everywhere, so even a home that does not have a mold “problem” will have some mold spores within the air. For a sample to be considered “normal” it should be somewhat consistent with the outside control sample taken that at that same day and time. In general indoor spore counts should be roughly 75% of the outdoor counts and usually proportionately similar in terms of spore types.
We do get asked all the time though “well, why can’t we just use averages from previous samples to determine a baseline?” Great question, and at first glance it does seem like a reasonable method, but in reality it just doesn’t work that way. Averages are used to some degree in the analysis of air samples, but an average is just that, an average. The spore types and concentrations in our environment can swing drastically due to multiple factors that influence our environment. Mold is a living organism, and therefore it reacts to its environment conditions. So, if it has been wet and rainy out and the mold sources are, let’s say happy, then they may not be actively sporelating and releasing mold spores into the air. On the flip side of that, when conditions are dry, mold sources typically begin sporelating in an effort to spread out and find additional water and/or food sources. On windy days, we sometimes see very high spore concentrations. And when there is snow on the ground, we will typically see very low spore concentrations.
As a result of all of these influencing factors, it becomes apparent that averages just do not give us enough information to properly assess indoor airborne mold conditions. To fully understand if there is a mold “problem” within a home, it is important to have as much information as possible. And a big piece of information that helps us do that, is analysis of airborne mold spore concentrations as compared to an outside control sample. If you believe you have a mold problem, consider engaging a competent and certified mold investigation specialist to perform a thorough mold investigation and proper mold sampling.
- Respiratory problems; including difficulty breathing, wheezing, shortness of breath;
- Sinus and nasal congestion and irritation;
- Irritation of the eyes — watery, burning, red;
- Sore and/or dry throat;
- Skin rashes and irritations;
- Problems with sense of smell;
- Typical symptoms normally associated with a cold or allergies; and
- Memory problems, odd mood swings, nose bleeds, body aches and pains, and fevers are occasionally reported in mold cases.
Mold exposure can also exacerbate other illnesses and conditions, including asthma. These symptoms are often worse for the young, elderly, or people with compromised immune systems.
If you have any of these symptoms and you believe they may be related to mold, it’s prudent to engage a mold inspection and testing professional to perform an analysis of your home and/or place of work.
Being in the mold inspection industry, we get asked all the time: “Is it good mold or bad mold”. To be honest, this is a tough question to answer. I think instead of looking at it as good vs. bad, it should really be lumped into 3 categories: Good, Normal, and Bad.
Let’s start with the good, shall we? Molds can be good when they are used for medicines, or in the production of certain cheeses, and let’s be honest, mold that is Outside our home is typically considered to be a good thing. So, most people don’t even notice mold when it’s good, unless they are reaching into the fridge for that stinky wine cheese they love so much.
Next, we come to normal molds. When talking about normal molds within the home, there are really two types. Airborne mold spores, and mold growth. When it comes to the airborne type, it is simply a fact of life that there is always some degree of airborne mold spores floating around in your home. They come into the home through any gap, penetration, open door, and even on our clothes from the outside, and are considered to be normal, as long as they did not originate within the home. Normal mold growth within the home occurs on a day to day basis. It could be that “mildew” in the corners of your shower, or that weird looking black stuff you see in your window track. What makes it normal, is the fact that it is growing on a non-sustainable food source, the surface is non-porous and can typically be cleaned away with normal housecleaning methods.
Now, for the fun part, Bad mold. To put it simply, mold growth within the home is considered to be a bad thing when it is growing on a sustainable food source, and is potentially affecting the air with what would be considered “elevated” mold spores which is quite a bit different than the normal airborne mold spores we talked about earlier. The food sources within a home are pretty numerous, and can include: Drywall, wood framing, wood subflooring, debris, contents, etc… What makes this a bad thing? Well, typically when conditions such as these start to occur, the proper removal of said mold is just a bit much for the average homeowner. Not only must the impacted materials be properly removed and/or cleaned, but the airborne spores in association with the mold must be addressed as well. The proper removal of a mold problem is a very technical process, and requires the right equipment, and is just not something that the average homeowner should take on themselves.
The first step a homeowner should take when they believe they may have a mold problem is to have the conditions assessed by a Mold Investigation Specialist. Through a thorough investigation and proper testing, they will be able to tell you if you have a mold problem or not. Or, if you really prefer the terminology, if it’s good mold or bad mold.
There is an abundant amount of information available at our fingertips regarding Mold. Much of it is relevant, accurate and useful information. The problem is that even the experts differ in opinion on some topics. As a Certified Mold Inspector, I see many different situations and unusual conditions in homes, apartments and businesses. I also hear comments and read information that sometimes makes me scratch my head. So, I thought I’d discuss a couple of my favorite Mold myths.
Myth # 1: Only Black Mold is bad.
Mold can present itself in many different colors, and while it is true that the most concerning types of Mold, such as Stachybotrys, are commonly black in color, many types of Mold that do not have a black appearance can cause adverse health effects for some individuals. Most Mold professionals agree that indoor Mold growth of any color is a potential health risk and should not be present inside homes and businesses. In addition, mold growth, of any color, inside a home or business is a sign of a water intrusion problem which can comprimise building materials, both structurally and cosmetically, and can be expensive to remedy.
Myth # 2: Bleach is an effective treatment for Mold
Bleach is comprised mostly of water and adding additional water to a Mold problem is kind of like throwing gasoline on a fire. It appears to get rid of the Mold initially, but all too frequently, the Mold returns in a short period of time and the problem becomes worse than before the initial bleach treatment. The other shortcoming of bleach is that it will not reach or eliminate Mold that is hiding in inaccessible areas. Such as inside wall cavities, under flooring, behind wallpaper, or Mold that is absorbed into porous building materials, such as drywall. In most cases, it is best to leave the removal and cleaning of a mold problem to a professional Mold Remediation Company.
Myth #3: You can just paint over Mold to seal it and prevent re-growth
Simply painting over Mold affected building materials does not provide a long-term fix to a Mold problem. We are often told by our clients that someone treated the Mold with bleach and then sealed (painted) the area. This is most often times just a band-aid unless the initial cause of the Mold growth is addressed and corrected. The underlying cause of most Mold problems is excessive moisture and wet building materials, commonly due to water intrusion, leaks or excessive humidity. If the excessive moisture problem is not corrected, repaired or eliminated, then Mold will most likely return.
More Mold Myths debunked to come at a later date. Thanks for reading.
One of the most common questions our offices receive is “Why do I need a mold inspection? Won’t mold sampling and testing tell me what I need?” From our experiences over the last 10 years, which includes tens of thousands of mold inspection projects across five states, we consider the mold inspection to account for about 75% of the puzzle and mold sampling and testing to account for the other 25%.
Both parts are important, but they must be done in tandem — you can’t just count on one to tell the entire story.
Rather than write abstractly about why you need both an inspection and testing, I thought it would be more useful to provide a number of examples to make my case. This posting will be the first of several hypothetical case studies I’ll present.
Our client, Mr. Brown, is in contract to purchase a new home. He wants to make sure that he has no water intrusion or mold problems that could cost him money to repair or that would cause his family health problems. But, Mr. Brown is concerned about the cost of the inspection and the testing. He believes his home inspector will do a thorough inspection, so he just wants mold testing in a few rooms and wants to skip the mold inspection. We warn him against this decision and try to explain the need for the mold inspection, but he won’t be swayed.
He asks us to collect air samples in a few rooms in the home; including the master bathroom and master bedroom. All of the air samples come back from the lab as ”normal”. Mr. Brown purchases the home and believes everything is ok from a water and mold standpoint. About a month after moving in, he notices a really musty odor in his master bedroom and is seeing some swelling of the drywall adjacent to the master bathroom shower. He hires a plumber to investigate. The plumber opens up the access panel to the shower plumbing and finds the inside of the wall full of mold. Mr. Brown is upset because he had mold testing performed in both the bedroom and bathroom and the air samples were normal. How could this happen?
A proper mold investigation requires both a mold inspection and mold testing. Had Mr. Brown paid for the mold inspection, the inspector would have used their moisture meter around all plumbing areas and places where water and mold are often found — like the areas adjacent to the shower. The inspector would have found elevated moisture and would have observed the staining and swelling of the drywall. The inspector would have recommended a wall cavity sample or invasive testing or both. The mold inspection service would have uncovered the mold problem.
Now, Mr. Brown is faced with a very expensive mold remediation project and repair of the drywall and shower. Since he has already purchased the home, he will likely have to pay for it himself. Had he spent just a little more money for the mold inspection during his due diligence, the responsibility to repair the shower and pay for the mold remediation would have been the seller’s.
That said, Mr. Brown did pay for mold testing of the air in the master bathroom and bedroom. How were those samples “normal”? The mold growth had an active source of water and food. Thus, it was not actively sporulating. And, it was trapped inside a wall cavity. Under these conditions, it is perfectly normal to have an air sample with no elevated spore counts in the air even though there is active mold growth in the area.
Again, this is why you need both a mold inspection — a big part of which is a moisture intrusion investigation — and mold testing.
Do you know the allergen levels inside your home? If you’ve been diagnosed with allergies you may have an increased sensitivity to certain allergens.
Knowing what levels of allergens that are present inside your home is the first step in determining if you are being exposed to allergens that may be causing adverse physical conditions. Minimizing your exposure to the allergens that affect you is a crucial step towards controlling your symptoms.
It may be impossible to completely eliminate all of the allergens in your home, but even reducing them can lead to a significant decrease in symptoms, less need for medication and improved indoor air quality.
What can be done if you are allergic to something in your home?
- We can test your home for many different allergens
- The most common test we perform for allergens is the ‘Allergen Screen’ or ELISA (Quantitative Enzyme-Linked ImmunoSorbent Assay)
- The Allergen Screen will determine if significant levels of some of the most common allergens are found in your indoor environment.
- If allergen levels are found to be elevated, we will provide recommendations on ways to reduce the allergens in your home.
Our Allergy Tests – The Details
The “Allergen Screen” will test for the following four most common allergens: Dog, Cat, Cockroach, and Dust Mites. Keep in mind that often times, you cannot see these allergens with the naked eye. In fact, the allergens are microscopic and can easily float in the air. Some allergens, such as dog and cat dander, are sticky and commonly cling to walls, furniture, flooring, and personal belongings, making them difficult to remove. If you live in a home or an apartment that was previously occupied, there could be high allergen levels due to the previous occupant’s pets. Allergen testing may be the first step to improve your indoor environment and overall quality of life.
Would you like to view a sample allergen report? Sample ELISA Allergy Report