That's absolutely true. And another example that might be related to what we find with mold or not mold that has to do with humidity because if you have a high mold growth you're going to have a humidity problem. Dust mites, as an example. Dust mites absorb their moisture through their exoskeleton, if you can hold the humidity down around fifty percent or so, you're not enough moisture for the dust mites to absorb the moisture they need to survive, and gradually the dust mites in things like the carpeting and that kind of thing, are going to disappear, over about eight weeks or more.
Absolutely, we can tell by the kind of molds that are in the environment whether or not they have had problems with high humidity, for instance. Because all mold needs to grow is oxygen, food, and moisture. And if you can hold the humidity down below around fifty percent, you're going to retard the growth of almost all mold spores.
But that's just not possible here in Atlanta, unless you use dehumidifiers, particularly during the summertime. So, in most homes, the environment for growing mold is there all summer long. Sometimes from April to November, they have an environment that mold can grow in.
We absolutely try to identify that if we see that there's circumstances, and we often learn why we're there is because that there's a suspected mold problem, whether it be a leak in the wall or whether there has been a leak in the wall. So under those circumstances, if we're looking to see whether that has an effect, we can take air samples inside the wall cavity, we can take samples on surfaces, we take air samples and other samples that might be related to that, we could take bulk samples back to the lab and have them analyzed. So we absolutely can do that and try to help that. But, even beyond that we can tell them the nature of the kinds of leaks and the kinds of problems that are associated with that. For instance, if it's a toilet backup, they could have a sewage type backup. There's guidelines that are published by the EPA or the CDC. If that happens on a carpet, that carpet should be replaced. Anything that's a porous material, if you can replace it, it should be replaced. If it's a material like the plywood on the floor or underneath the carpet or something like that that you can't necessarily replace, then it should be treated properly and sealed and encapsulated and that kind of thing before you put it back together. So we can provide some of that information – about how to properly prepare it as part of our investigation and part of our report.
One of the other things that we're finding when we find damage like that and especially if they've gone in and they've done some sheet rock work or done some other kinds of work. A lot of times we hear stories that, "Well, they've come in and they've done this and I'm still having these health symptoms." The background particulate in the air is a really important part of indoor air quality health and it's a really overlooked part. I don't understand exactly why because there's literally hundreds, if not thousands, of studies globally about the problem that background particulate provide causes for breathing difficulties and other things in the indoor environment. But when you're doing drywall work and all that kind of stuff, the particles, the dust and stuff that's in the air is going to spike. And those can cause serious health issues also especially with breathing difficulties. And the way that you get that out of the air is with filtration. Again, it goes back to what we've found on these HVAC systems, which is your primary source of filtration for the indoor environment. The filters that they have in those are statistically equivalent to no filter at all when it comes to particles as such small as respirable particulate. And that's the one that causes the big damage.
So people can be exposed to this background particulate, either from work that's being done or from deterioration in the indoor environment due to some of the damage that has been done that doesn't show up in most reports – some of the reports will show that it's 1, 2, 3, 4, or 5 on some kind of a scale like that. And some of them refer to it that, whether or not this is likely to cause enough debris on the slide to prevent an accurate count of the particulate. But they're not looking at the particulate itself as a health cause to the individual.
We actually do a statistical count in at least three cells to give an idea of what the background particulate is in the indoor environment. We find that the background particulate indoors is most often much higher than outdoors. And in some cases, much much higher. To give you an equivalent, see, we took air samples from 56 locations that were taken during the code yellow and code red we have because of the fires up north. And in those air samples, about 24% of the samples had particulate levels above 200,000.
What we're finding in the homes, and we're biased towards those that have some problems, is about 25% of the indoor air particulate is higher than 200,000. So in many cases in these damaged homes we go into, the background particulate is high enough that if it were in the outdoor area that they'd have code yellow or code red declared, you know, and nothing has being done about it, and these filters that we have in there, are incapable.
We can do a similar kind of sampling that we do in the carpet for furniture. We have a portable vacuum with a special nozzle and a special gasket that will be able to capture the dust that contains the mold spores. We can vacuum that furniture and we can learn something about it in terms of the quantity of spores that are on there and whether or not they’re likely to be growing at that time or not.
If it's a fabric, we're measuring the dust that has settled down into the fabric. If we're looking at the framing where it's been water damaged in the bottom, there we would maybe take a tape sample or swab to find out whether there's mold growth that associated with water damage. We can learn about that in terms of furniture by taking those samples.
Our database isn't that complete in the furniture side of it as it is in the carpet dust, but we can imply based on what we seen in the carpet dust to what we see in the furniture to give some guidance as to whether or not it's likely that can be cleaned up or whether it should be discarded.
As I've mentioned before, we can imply some things about pest control, for instance, that might be in there. We can learn if there's likely to be some chemical collision in the indoor environment. In some cases, we can read that into it. If we know that, let's say, we know there's visible mold and you have a real low airborne count, but you know it's being suppressed for some reason. We can tell something from the symptoms that the people say is whether or not there can be.
There’s three things that may really relate to mold and that is if you see it, obviously that's an issue; if you can smell it, the odor that's given off, the musty odor that you smell from homes or in homes are the gases that are given off while mold is metabolizing whatever it's growing on. So if you smell that smell, mold is growing somewhere; and the third thing is any kind of health symptoms particularly that are associated with the respiratory system, whether you're having sinus problems, whether you're having any kind of breathing issues.
But it's not limited to that – mold problems go far greater than that for a variety of reasons. One of the reasons is that 70% of those who have asthma also have allergies. They have allergies to the mold spores and when you have, and a lot of people have allergies, you don't have to have asthma to have these allergies, when those get into your windpipe and your respiratory system, you get this redness and swelling just like you would get on your skin if you have your skin broke out some way. And that impairs the mucus system from working properly and those little areas that are rough like that become places where bacteria and viruses can get into your system and cause other kinds of diseases.
There are some studies that suggest that between 10 - 30% of all diseases associated with particulate are associated with indoor air. The other way that it can harm you is that, in sufficient quantities, these spores that carry these toxins, they get down into the, they're small enough to get into the alveolar where the oxygen is exchanged with your blood and your body will break those up and then those toxins go out into your blood and they can go to other organs in your system as well and cause damage elsewhere.
The other thing that we're finding, some recent studies have shown that there was one study that looked at data from 14 states and concluded that 90% of the dust in those homes that were studied contained chemicals that were considered to be unhealthy chemicals. 90% of them contained 1 of 10 chemicals, including one of the chemicals that was a carcinogen, a known carcinogen.
We found that there's about 25 spore types that were positive for that ratio for what we found in the carpet dust. We've done the same thing for allergies and we've done the same thing for respiratory problems and each of them had something in the mid-20s that different spore types were associated but when you look at all the health symptoms that we have found, and we've taken those ratios for all of the different spore types that we've found, about 62 of the 70 spore types that were found in any quantity were associated with, were found more often in homes where there were one of the health symptoms that we track.