More airborne mold spore count report or number questions & answers-set-2:
This article series discusses the possible significance of different levels of indoor airborne mold spore counts and mold test reports.
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These questions and answers about how to interpret the mold count returned by various mold tests were posted originally
at AIRBORNE PARTICLE & MOLD COUNT NUMBER GUIDE - topic home. Be sure to see the advice given there.
to editor Hi, I have been trying to find a source that lists what are considered to be safe and reasonable mold airborne counts for a home. Do you have this or can you direct me to a resource. Appreciate your help. - P.P. 5/17/2013
Sure:
Please be sure to review ALL of the articles I suggest below - otherwise you would be in danger of a possibly harmful or costly misunderstanding
In the article listed just above we state:
The third article points out that airborne mold counts are close to junk science because of the range of variability that encompasses several orders of magnitude.
Furthermore, since among the 1.5 million or so mold genera/species there is wide variation in particle size, probability of growing as an indoor mold, and toxicity, it is rather unreliable to consider only "mold count" without knowing something about what mold is actually present in the building as well as what molds are being detected in a test.
Generally we might include airborne counts as PART of a building screen for harmful mold levels, interpreting it based on what we know about how the measurement was made, the building leak history, and other critical observations. In general there are count levels (you'll read above) considered to be consistent with generally low levels or homes that have probably not been flooded, but I warn that even a low airborne mold sample could contain low levels of particles (such as Pen/Asp spore chains) that would be a strong suggestion that even at a low count there is a high probability of an important hidden harmful mold reservoir that simply was not detected by the "air test".
An optional fourth article to see is
Let me know if any of that material is unclear or confusing and I'll do my best to help further.
I saw your website and it is very informative. I work in a library that I believe has mold due to water leaks, although there are no outward signs of mold. An air quality test was recently done and it showed some fungi spores such as Bipolaris and Cladosporium, but the outside air quality was shown to be much worse and I do not see how that is possible.
A comparison was made between the outdoor and indoor air and their conclusion was that "The bioaerosol results in [Anonymous] Library for total fungal spores did not identify an amplification or biodiversity of fungi between the indoor and outside sample."
No recommendation was made because I assume they feel that the indoor air is a minor issue when compared to the outdoor air. I have been having high blood pressure when I am in the building, but my blood pressure goes down to a normal level when I am outside, so I do not see how the outside air could be much worse than the inside air according to the test results. If I sent you a copy of the results via email, would you be willing to look at it and to see if this test looks legitimate? - Anonymous [data on file] 1/22/2014
Send me the report and I can comment. Keep in mind no remote analysis is a substitute for an onsite expert. I will take an initial look and comment pro bono. ...
[Reader provided a copy of an indoor IAQ inspection and test reports provided by an industrial hygienist. The hygienist performed a visual inspection, tested CO2 levels, and performed some air tests for mold. - document on file]
The details of the tests and lab report do not find evidence of an indoor mold contamination problem.
None of the species found in the actual "test" included the more problematic indoor spores that are most common in buildings where there is a serious mold contamination issue - such as in the Aspergillus group (highly airborne, small particles, breathed deeply into lungs, pathogenic or toxic) nor of the mycotoxin group such as Stachybotrys chartarum that is often found on wet drywall.
While the hygienist cites that there are no mold exposure standards, that is not quite the case. While I argue vigorously that a simple quantitative standard for mold exposure would be junk science (individual mold spores vary enormously in size, toxicity, airborne or other exposure pathways, so we would need hundreds of standards), nevertheless, experts have shown that there are general indoor mold levels that strongly indicate that a building has been subject to leaks and / or that there is probably an actionable (that is large) mold reservoir in the building.
See MOLD EXPOSURE STANDARDS for details.
And even when indoor mold test counts are low, on occasion one may find subtle clues that mean one could infer by looking at mold genera/species found indoors (which certainly were not matched to the outdoor spore mix) provide a very weak or low-level suggestion of water intrusion or leakage - that is, we see some mold growth that might be associated with water leaks.
The risk in any air test is that the airborne spore level can vary by several orders of magnitude depending on how the test is conducted. So absence of evidence of a mold problem when we rely principally on an air test is *not* proof that no problem is present.
But absence of such evidence, when combined with an expert inspection of the building for visual clues suggesting an actionable risk of a hidden problem reservoir (such as mold contamination in a ceiling or wall cavity) can add up to a conclusion that the expert could not find any justification for more invasive or extensive inspection steps.
I cannot comment on how expert the visual inspection was at your building. The reliability of that step depends largely on the particular experience and building-science knowledge of the inspector.
I can comment that comparing indoor air with outdoor air, while a very widely used practice, is rarely actually useful. Too often the genera/species are so different that simply comparing "spore counts" is nonsense - as comparing apples and oranges. The hygienist's own report makes this same pont.
I can add that sometimes, even very low levels of certain problematic mold spores in an indoor sample (such as Aspergillus spores in chains) can be detected by an astute lab technician and interpreted by an astute investigator as reason to look further for a building problem. At InspectApedia.com we have published a series of articles about these sources of error or of discovery should be considered by hygienists or other professionals who inspect or "test" buildings for mold or other similar contaminants. Two you may want to read are
ACCURACY OF AIR TESTS for MOLD and ACCURACY vs PRECISION of MEASUREMENTS
The first article introduces the huge variation in airborne particle levels from minute to minute in a building as well as other sources of error that can overwhelm mold test accuracy.
The second article is interesting because a careful read of a typical mold-in-air test will show that sometimes data is being given where only a single mold spore of a given genera/species was actually detected. At that excruciatingly small count level one should not get excited about the translation into percentages. For example if indoor air contains "25% of toxic mold type X" and then we read that only four spores were detected in the whole sample, and one of these was type X, then such numbers are of little import. The devil is in these details.
In sum, nothing in the report you provided points toward an actionable indoor mold contamination issue nor documents a basis for more invasive further inspection or testing. That's not to say that the building is guaranteed "problem free" but it is reasonable to opine that an expert has examined the building and found no evidence that justifies further such action. For a more thoughtful look at how we decide when expert building investigation is probably warranted, see MOLD / ENVIRONMENTAL EXPERT, HIRE ?
If you are still convinced by your own experience that the building is responsible for personal health complaints then you will want to confer with your doctor and document his/her opinion, or that of a referred expert in environmental medicine, that your complaints are environment-related, caused, or aggravated.
For example, your doctor might cite other reasons for elevated blood pressure (your complaint) than an environmental one. Mold contamination itself is not usually blamed for high blood pressure, but in my opinion stress, including environmental stresses or even simple anxiety could be relevant factors.
If that conclusion is indeed reached, then next would be an examination of all environments where you spend the majority of your time, to see what can be found, if anything, that should be addressed.
Finally, I recommend caution against becoming a victim of a "capture error" - that is, don't let a specific fear that has come to mind (mold contamination) prevent you from looking more thoughtfully and broadly, and with medical advice, for the cause and thus recommended actions around a medical or health complaint.
On 2018-12-01 by (mod) - just had an air test for mold - what does it mean?
Unfortunately is a building screen for mold contamination and air test by itself - with no inspection and no extremely-high airborne mold count - is quite unreliable and the results that you quote probably meaningless.
A thorough inspection for visible mold, building leaks or leak history, and similar clues would probably be more useful and more reliable.
That's because a relatively low mold count risks a false negative- missing a mold problem. Mold counts vary by 4 orders of magnitude or more depending on test conditions so 1 "dead Stachybotrys spore" (how on earth someone knew that is mysterious) has no meaning - it could be 1 or 10,000.
See AIRBORNE MOLD COUNT VALIDITY
and AIRBORNE PARTICLE & MOLD COUNT NUMBER GUIDE
On 2018-11-30 by Bruce
Just had a air test for mold, the house has been vacant for a year people in and out for the two weeks prior the indoor air count was total of 1135 m3 and out 1824 m3 1 dead stchybond spore was found . No mold visible to the inspectors and no leaks should i be concerned
On 2017-12-15 by (mod) - mold remediation done for Stachobotrys
Lisa
Of course given the significant inaccuracy of all airborne mold tests means that we cannot assert any absolute conclusion.
It is perfectly normal to find a few mold spores of the same genera/species as dominated the mold cleanup job.
However in general, unless the ascospores (Ascomycetes) were dominant in the area that was being cleaned they are more-likely to be visitors from outdoors.
Take a look at a more-reliable visual approach beginning at MOLD CLEARANCE INSPECTIONS - https://inspectapedia.com/mold/Mold_Clearance_Inspections.php
That article continues with at CLEARANCE PROCEDURES where we give details of when, where, and how a post mold remediation job inspection and test should be performed, and also with WHEN TO STOP LOOKING FOR MOLD
On 2017-12-14 by Lisa - Should I be concerned about the low levels of Stachobotrys and high Ascospores?
Hi there,
We had some mold remediation done for Stachobotrys in our bathroom shower wall of our bedroom.
The contained are came up clear, 1 raw spore in the other section of the bedroom, and a count of 12 at the other end of the house in the family room. Some of the workers and my husband did walk through the house and could have had it on their shoes.
We also had high ascopores of 1600 to 1800 in both areas, but 0 to low penicillin/asp and Chatomium, 0 Basidiospores, and 0 Fusarium
Should I be concerned about the low levels of Stachobotrys and high Ascospores? Regarding the ascospores, both area were by sliding glass doors with entrances to the backyard which is full of dead leaves.
The mold remeciation company is asking if we want more tests and remexiation done. Thank you for your help!
On 2017-12-04 by (mod) - Aspergillus/Penicillium in large amounts in the crawl space
Tammy,
Yes if the results are accurate the situation will almost certainly need to be corrected. I would want actual reliable visual information and not just a "test" that is neither diagnostic nor prescriptive.
On 2017-12-04 by Tammy
The Potential buyer of my home has identified Aspergillus/Penicillium in large amounts in the crawl space underneath my great room. Is that a concern?
On 2017-09-16 by (mod) - counts in your mold test report could certainly indicate an indoor mold problem
Eric,
Those counts in your mold test report could certainly indicate an indoor mold problem because the absolute count was high.
The comparison with indoor and outdoor mold counts ONLY makes sense and is ONLY useful IF we know for sure that we are looking not just at the same general "type" or "genera" of mold but at the very same mold species.
The underlying theory was that we were going to try to avoid calling out as an indoor mold problem mold that just happened to blow in the window around the time an indoor air test for mold was performed.
Since getting mold identified down to the exact species is often beyond reasonable cost or test scope, we're not sure what to make of such count comparisons, even though everybody loves to obtain them.
On 2017-09-16 by (mod) - air tests for mold have a lot of variability - additional on-site information is needed
Mandi,
I am sorry to say that "air tests" for mold are unreliable: the actual count can vary several orders of magnitude depending on how a test is conducted, so a number of 270 could be 2.7 or 27,000 in actual truth. Worse, an air test does not tell us what needs to be cleaned, nor where the mold reservoir is, if there is one that needs action.
So the number is not very helpful without a competent onsite inspection to find the problem mold reservoir OR to tell you that enough looking in the most-suspect areas means that further action isn't justified.
The next time you hire a "mold inspector" my advice is to withhold payment until you are satisfied that you understand what is meant by the report you receive. An inspector who won't provide that help is ... not helpful.
On 2017-09-16 by Mandy Janicki
This is our second mold testing. Caldosporium came back at 270/m3 and penicillium/aspergillus came in at 1300. We are set to move in a few weeks. They said they will clean the vents to help remove the rest of the count. Not sure if this is a good number or not.
On 2017-09-15 by Eric
My son was away from his apartment for a few months and upon his return he discovered there had been a leak and the unit had mold.
The owner of the building repaired the unit and gave us the below information regarding its mold testing. Is it safe for him to return to the unit?
Air samples were taken Friday (9/8/17). The results (reported in total spore count per cubic meter (spores/³cm)) are as follows;
Exterior of the building: 22,350 spores/³cm.
Inside #109: 13,293 spores/³cm (0.5947% of exterior).
On 2017-08-07 by (mod) - culture plates won't detect all mold genera/species but the car company told you to take a walk
Denise
I understand why you'd be frustrated and annoyed, as would I with people who more or less blow you off to avoid trouble for themselves - at least that's what it sounds like. Even though the tests you performed, especially if you used culture plates, are innately inaccurate, the worst inaccuracy is when such tests do NOT find evidence of mold - a false negative - when in fact there is a mold problem to be found and removed.
If your car smells like mold, which can happen if interior padding or carpets or headliner etc get wet, the solution is to find and remove those components, clean the surfaces, then air out the car, then restore it. Sometimes those costs are prohibitive.
I'm not aware of a government agency willing to step in to this individual consumer problem, especially with our current government's view of reducing government size, services, and protection. You can complain to your local better business bureau, and you can register what you believe is a health concern that could affect other consumers facing similar car leaks
by notifying the US CPSC by reporting that under some situations your car is an unsafe product - https://www.saferproducts.gov/CPSRMSPublic/Incidents/ReportIncident.aspx
- however I think the CPSC would reviewer might think that without a sufficient number of complaints this particular issue may not be an innate design or materials hazard in the car itself.
That leaves applying the lemon law which, depending on where you live, can be effective at demanding a new car if you've asked and failed to have a serious health or safety or other hazard corrected at least three times without success.
Keep me posted.
Also see CAR SMELL - Mold DEODORIZING https://inspectapedia.com/odor_diagnosis/Odor_Diagnosis_Car_Mold.php
and be sure to see also CAR MOLD CONTAMINATION https://inspectapedia.com/mold/Car_Mold_Catastrophe.php
both easily found again (if you lose these links) by searching InspectApedia.com using our on page search box to find "CAR MOLD"
On 2017-08-07 by denise marcoccia
My vehicle had a faulty evaporator core. It took Infiniti almost a year to determine where the musty mold smell was coming from. They removed the evaporator core but did nothing to remove the mold.
The service tech said it was really "bad" I did mold test before and after and it is worse now level are 2600 asper.penicillium, 40 stachybotys, 200 basidiospores, 40 ascospors, 40 ganoderma. I'm allergic to Penicillin, my health over the last year has been horrible barely getting to work 2 days a week.
Car company saying the results are "inconclusive" and there was no mold..they never tested for it. The manufacturer Nissan says it's the dealers responsibility the dealer is saying it's the manufacturer's responsibility. Neither are doing anything.
Can you advise a government agency that might get involved? I am just over guidelines for lemon law...
On 2017-07-12 by (mod) - mold testing is not useful in some situations
Janet,
Unfortunately mold testing is not at all useful for the situation you describe - and its results would not change what action is or is not needed. Furthermore, while elevated levels of Pen/Asp (IF that's what's really there, which is arguable), are a health risk to building occupants,
If I can be frank in my OPINION, everything you were told (or that was reported to you and that you report to us) points to someone who doesn't know mold from molasses.
One can't say based on a "test" that a building needs to be demolished, and nobody in their right mind could to argue that based simply on detecting 31 physical mold spores of Aspergillus indoors that a building needs to be smashed up.
Depending on the test performed and how it was conducted, the data could be wrong by up to 4 orders of magnitude.
One does not "treat" mold - "treatments" like mold killers are the incorrect approach, don't fix the problem, and risk leaving harmful particles in the building.
An inspector whom you hire has a legal duty to report his or her results to you and to NOT report results to others except if s/he thinks that there is an immediate life safety threat to those others (unlikely as they're not living in the home) so your inspector has behaved unprofessionally, improperly, unethically, and possibly illegally as well as incompetently. Just sayin'
What's actually needed is a thorough inspection by someone who knows more than your "mold tester" and who will
- find the mold reservoirs
- define the extent of cleanup needed
and then a handyman (for small areas under 30 sqft of contiguous mold) or a professional cleaner for larger areas who will
- remove it or remove materials that can't be cleaned, like drywall
- clean the remaining surfaces
- fix the cause
- restore everything
On 2017-07-11 by Janet
We are in the process of selling our home and the buyer during a home inspection found signs of dried mold and active mold (moisture barrier was not fully dispersed during remodel).
We immediately stated that we would pay for the mold testing as we had no idea this was an issue or we would have addressed it immediately and felt that we wanted to make sure everything was right. The Air analysis in the Living Space on the main floor was Normal, The basement stated Problem with *Indoor Problem Fungi - Aspergillus 31 Raw Count, 208 Spores/m3, % of Total 25% **Non-Problem Fungi Penicillium/Aspergillus 51 raw, 342 Spores/m3, % of Total 42%
. The inspector will not call us back however spoke to the buyers (who did not pay for the test) and stated that these numbers were extremely dangerous and could never be treated with success. They would be better off tearing down and rebuilding. I am not a brain surgeon but can't help but think something is not right here.
On 2017-07-06 by Bob Kenworthy - sp
We recently moved to our new home and found it had been flooded for several month prior to our arrival. Needless to say, it was a major loss. My question is this: After removing EVERYTHING, to include all insulation, walls, ceilings and floors, the mold remediation team took air samples immediately after completing deconstruction.
There is a LOT of dust and the entire house is open to the outside. The air samples taken show Penicillium/Aspergillus types ranging from 31,000/m3 to 53000/m3 in the room where the last deconstruction was done. The mold team did spray for mold on the rafters, floor joists and wall studs just prior to taking the readings. Is it possible that all of the dust and debris in the air is causing artificially high numbers?
The lab doing the analysis reported Sample Clarity and visibility as Moderate, with all other tests for Cladosporium species spores, Basidiospores, "Marker" spore types, (Chaetomium) and "Other" spore types, (Other brown, Smutes, Periconia, Myxomycetes), returning counts similar to outside samples.
I am thinking I should do a better cleanup and spray everything with Total Solutions Lemocide before rebuilding just to be safe. Your thoughts or suggestions would be greatly appreciated!
On 2017-06-23 by BarbB
Daughters bedroom was tested and 150000 per cubic aspergillosis and penicillin air borne spores were found and my daughter has had years of respiratory sickness and asthma diagnosed 2015 I'm at a loss...
On 2017-05-27 by (mod) - what does a total spores per m3 of 1820 mean? Not much. level of airborne particles in a building varies by 1-4 ORDERS OF MAGNITUDE
I'm sorry to say, almost nothing.
"Mold Tests" especially air tests for mold contamination are not reliable in part because the level of airborne particles in a building varies by 1-4 ORDERS OF MAGNITUDE depending on when where and how a test is conducted. So 1820 could be 1.82 or it could be 1,820,000 spores/M3 of air.
What's needed is a visual inspection to find where there is mold, to define what cleaning is needed, and what caused the wetness and thus the mold growth - as that must be fixed or the cleanup won't be effective; and if there is a large area of more than 30 sqft. professional cleaning is needed.
On 2017-05-26 by Anonymous
this basement has been wet, the test result is that the total spores per m3 is 1820, what does it mean
On 2017-03-17 by (mod) - out of context a mold count number doesn't help tell us much at all
Out of context the "number" means absolutely nothing.
We have no idea what inspections were made, what mold is or was present, what sort of test was done, what number or reporting scale is being used.
You are entitled to demand that whomever was paid (probably plenty) give a useful interpretation of what they found. Or get your money back and hire someone useful.
Keep in mind that "counts" particularly airborne mold counts can vary by 4 orders of magnitude ("1" might be "1000") depending on test conditions.
On 2017-03-17 by Barbara
I was told by board member that a report number of. #7 from an inspection was low and wasn't serious. W
This is in a club house at the Complex. What does this mean?
On 2017-03-10 6 by (mod) - the spore number isn't helpful unless we know what spores
Tam:
The absolute number of spores may be less diagnostic than what is the spore mix; for example if Aspergillus or Penicillium are the dominant particle in an indoor sample I suspect the cleanup may have been incomplete.
An on-site expert should review the work that was done, the success of it, the clearance inspection and test, and then the building history and actual condition for possible mold reservoirs.
On 2017-03-10 by Tam
We had a flood in our basement, there was some mold, then company left wet dry wall which created more mold, asbestos was also found and remediated.
They did an air clearance test that passed, said it was safe to go back. I continued to become more unwell as time passed, after remediation/reconstruction.
We had an independent person come into do another air sample and found slightly elevated mold spores upstairs but not downstairs where the house was remediated, in comparison to outside. We know the company did not cover the vents when remediating, left vapour barrier open and turned on the furnace!
So I assume they created airborne spores.
Q -Why would the count be higher upstairs now than down? I recently spent 5 days in hospital with sever asthma complications so trying to problem-solve in anyway I can. Thank you!!
On 2017-01-13 by (mod) - mold counts tossed over the wall are not nice
Brian
OPINION: If the people you hired to make "measurements" are not going to explain what the results mean, you should start by asking for your money back.
I do not assume anything about the crawl space from just your brief text. Sure mold spores might be mixed in with dust, but in a crawl space if there's mold contamination it's probably going to be found on organic surfaces (wood, paper, framing, subflooring) and sometimes in insulation. If the crawl area has ever been wet the risk of mold contamination there is greater.
Nobody in their right mind would pretend to give instructions to protect your workers from a brief e-text and a questionable mold report. Sorry.
On 2017-01-12 by Brian Pruden
5 air samples were taken in different locations in a crawlspace under a large building with a dirt floor and came back with readings of 16,000, 2,800, 400, 3,700 and 6030 Count/M3 of Aspergillus/Penicillium.
Visual inspection did not detect any mould reservoirs. The crawl space is dry and dusty and its assumed the spores were part of the dirt dust. Does this represent a hazard to workers and if so what should be done to make sure workers are safe.
On 2016-12-02 by Priscilla Palacio
We found penicillin, aspergillus and cladosporin in our home but most concerning is we found 38 spores stachybotrys and 17 chaetomium in bathroom. mold guy said not to worry, probably blew in window.
if that's true why not in whole house? SHOULD we move? REMEDIATE?
On 2016-12-01 by Nicole Smith
My mother passed away and when we moved her belongings we discovered mold on her walls and carpet . We had it tested and came 300,000 particles per..they said it was very high and toxic . The mold was Aspergillus.
My mother lived there for 5 years and lost 50 lbs, was in the hospital numerous times for dehydration and once with pneumonia . Could this high level of mold be a cause of some of her health issues ?
On 2016-11-01 by CHRIS - should I be concerned about these mold levels?
SHOULD I BE VERY CONCERNED ABOUT THE LEVELS? IM YET TO SEE ANY THIS HIGH ON HERE
garage mold exposure levels spores/m3 is 290,000. basement is 21,000 and kitchen is 6,900. garage raw count is 508. also has basidiospores180m3 and cladosporium 360m3 raw 4 basement 21,000p/a raw 477 clad. 1,400 raw 16 kitchen/a 6,900 clad. 710 raw8. how bad is this?
On 2016-10-11 by Priscilla
My indoor air mold sample had <1 chaetomium. and a host of other molds 1200 for penicillin and aspergillus.
i'm very concerned about my safety and my family. the mold guy said it's not significant number. how serious is it? my apartment was very small 1 bedroom. i got itchy, sneezing, headache, nausea whenever inside apartment>
...
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