John Maher: Hi, I’m John Maher. I’m here today with Robert Weitz, owner of RTK Environmental, an environmental testing and consulting firm. Robert is a certified microbial investigator. Today, we’re talking about checking, testing, and removing mold. Welcome, Robert.
Robert Weitz: Thank you for having me, John.
John Maher: Robert, how do you check for mold?
Robert Weitz: Checking for mold in that terminology is really doing a visual inspection. We want to walk through a dwelling or an industrial/commercial building, and we want to visually see if there is any mold? Has there been any water intrusion or dampness or humidity that may cause mold and thereby may show itself.
Now a lot of the times, there’s hidden mold – and we’ll get into that in a moment of how to test for that – but really checking for mold is a visual inspection.
John Maher: Okay. So then, how do you test for a mold? Is that different?
Robert Weitz: Well, yes. Testing for a mold can be done in a couple of different ways. Once we see mold, if we do, then we can take an actual sample of that mold, either a bulk sample or a tape lift – it’s called – which is a microscope slide that has the sticky surface on it that we can actually press into the mold. And then, we can identify under a microscope what type of mold it is and what the concentrations are. So that’s one part of testing for mold.
Another part of that process would be to take air samples. The advantage of air samples is they help us to see what we can’t see. We want to identify what are the spores in the air, what kind of spores do we have? Have those spores cross-contaminated or migrated to other parts of that structure that may need to be included as part of a mold remediation plan?
We can do surface samples. Sometimes, we can take a swab sample if it’s difficult to access an area. But the swab samples, quite honestly, they tend to crush the mold spores, so it makes it more difficult to analyze and to see what kind of spores they are. So we find that the tape lift samples works much better.
John Maher: Does the air sampling or the air testing tend to show the types of mold spores that might make me sick?
Robert Weitz: It will do that, yes, with the two types of mold that are out there – one is called the toxic spore type and the other is what’s called an allergen. So, it does make a difference because one of the two can make you more sick sometimes, depending upon whether or not it’s toxic or not.
It really doesn’t make any difference whether the mold needs to be removed or gotten rid of. Regardless of the type of spore, we still need to get rid of the mold and the spores and to clean the area, so we get the air levels back down to normal.
John Maher: What are the methods that you can use to remove mold?
Robert Weitz: Removing mold is done by a remediation company. We work in concert with that sort of company. We do not do any remediation ourselves. RTK is totally independent in that respect. We have no conflict of interest. Our report is never biased in one direction or another, because we don’t do the work. So, the report that we provide is going to be straight and clear. It’s going to be based specifically on what we saw and what the testing results are.
When a remediation company comes in, they’ll do a bid based on our report and our recommendations. Mold can be removed in a number of different ways. Sometimes, depending upon the surface, it can be cleaned, and very often, sealed with what’s called an anti-microbial sealer. It can also be removed, meaning that the component that it’s growing on would be completely removed.
This would be the case, particularly, in a wall material, particularly sheet rock, because that is a paper material and mold loves to grow on that, but also hardwood floors that are put together with a tongue and groove construction.
Even though you may not see it, there can be mold in between the tongues and grooves, and is very likely in a water intrusion. So, the remediation method would be to remove the component completely but then, the underlying structure would be cleaned (unless that material is rotted) and then sealed with a specific sealer that will seal in the remaining roots or what are called hyphae that may remain in that structure after the cleaning is done.
John Maher: And obviously, any kind of issue that might have caused the mold in the first place will need to be taken care of. Any leaks in your pipes or flooding issues that you might have due to certain problems with your home or your business, those things will need to be fixed as well.
Robert Weitz: Absolutely, you really need to deal with that initially before mold remediation even occurs. If you have a pipe break, obviously, the pipe needs to be repaired. If it’s a humidity condition, like we’ll see very often in this part of the country, that would be in a basement where airflow is restricted and you have a high humidity level because it’s underground, we can just have an issue widespread from just a high humidity level.
So there’s all different types of exposures. In an attic, for example, we may just have lack of ventilation. Sometimes, attics aren’t vented properly and that can create a build-up of hot, humid air and those spores are going to attach itself to those surfaces, and they’re going to grow there because they like that wet cellulose material.
John Maher: So, one of the things that you might be able to do to start – especially like you said, in a high humidity environment – would be to set up some sort of ventilation, so that the air’s moving, and maybe a dehumidifier?
Robert Weitz: Exactly, yes. Mostly, in a basement, we would set up a dehumidification system, not us but a separate company. And that would help to keep the humidity levels down. We like to see levels down below 50%.
A lot of times, we’ll go into basement areas where there is widespread visible mold, and the levels may be 70% or even 80% and mold just loves that. It will grow very quickly in an area like that. Again, referring to an attic, the attic typically will have a lack of ventilation and that’s what causes the mold to grow. So simply by putting in any one of the number of different methods of ventilation will help to prevent that growth in the future.
John Maher: Great. Well, thanks very much for speaking with me today.
Robert Weitz: Thank you very much, John. It was a pleasure.
John Maher: And for more information, you can visit the RTK website at rtkenvironmental.com or call 800.392.6468.
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