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What is Post Remediation Verification?

Hello and welcome to this week's live stream. I'm talking to you today about post remediation verification, and you're probably thinking why is this relevant to me? Well, think of post remediation verification as a test or an exam that occurs at the end of a water damage and mould remediation project. And it's something where you'll be very interested in the results, because you want to make sure that the post remediation verification passes your property. And I'm going to be going through some of the situations and some of the factors and the features of PRV, as it's shortened, and why this is really important to your building, and why your insurance assessor is probably going to insist on the PRV, and why you need to read a copy of this at the end of the mould remediation exercise.

But before we start, I'm going to show you a quick video. And I'm going to preface this by also saying that earlier in the week I did a PRV on a property for an insurer, and this is the fourth or fifth time that I've been out to this particular property to do a PRV. Because guess what? It keeps failing, and really that's a disaster for the client. The client is still out of her home. She's been in temporary accommodation for the better part of a year and a half now.

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Now, this was a water damage breach which occurred in her kitchen, which damaged some of the timber framing and plasterboard in her home. Unfortunately, the contractors that the insurance assessors sent out to begin with were really, really slow, and you could almost say weren't very good at their job. And so here we are some 18 months later, doing successive post remediation verifications on this property, because unfortunately the results of the remediation demonstrate that mould still remains in some places, as we've gone through the PRV, at quite high and hazardous levels.

In any case, as I said, I've just completed the PRV testing earlier this week, and fingers crossed for everyone's sake it's going to pass. But I'm going to show you a quick video to put all of this in perspective, and then I'm going to go through some of the key facts about PRVs.

In this quick video, I'm going to be talking to you about something called post remediation verification, and explaining to you why this is really important and in fact fundamental to any mould remediation job for water damage that might take place in your home.

I'm standing here in this home today, which has been extensively stripped out and remediated using media blasting in order dislodge all the mould fragments which were attached to the wood due to unexpected water ingress, which then took hold and grew all over these timbers, and then eventually the plasterboard. So basically post remediation verification is a scientific way of quantifying what the mould levels are on surfaces, and also in the air.

And so we'll be going through some of the methods, and why you must insist on this from your insurer or for any mould remediation job that you have done in your property. So you don't end up in this situation whereby the whole home has to be essentially deconstructed to remove all the mould. But even if that happens, you must insist on post remediation verification. And I'll be going through what this data should look like, and what you must make sure you have in your hand in terms of accurate scientific information. Thanks for watching.

Okay, so why is this important? Well, it's important because the prevalence of damp in the built environment has been estimated to be somewhere between 10 and 50%. That means that up to one in two buildings suffer from water damage at some point in their life. And when there's water damage there is a high probability that there's going to be mould following. And in these situations sometimes the mould growth gets out of control, and you might need to get in professional restorers to deal with the after effects of the water damage.

And in fact, the World Health Organization have produced guidelines for indoor air quality that cover dampness and mould. And this is a particularly useful document, which talks about a lot of the qualitative and quantitative approaches to water damage restoration, as well as the reasons and all of those individuals that might be highly susceptible to mould.

But before I get into post remediation verification, I want to highlight a paper that came out in 1954, some 65 years ago, by Dr. Kate Maunsell in London. And she wrote this very elegant paper that focused on the topic of what happens in a home when it's undergoing, as she put it, redecoration. Essentially this is renovation. So imagine someone is publishing a paper 65 years ago, and they are focusing on the great increase in spore production, fungal mould spores, which occur during this redecoration or renovation event. And essentially this publication is the first document that I was able to find that was linking fungal spore cross contamination which occurs during remediation.

And I think that this is really fundamental to highlight at the outset as we get into discussing some other key points about post remediation verification. Now, you have to look at this essentially a little bit like a test. So there is a macro micro view, or lens that you need to look at at your post remediation verification. And obviously there needs to be a visual inspection which occurs at the property. There also needs to be a focus on ensuring that the water which caused the mould in the first place is actually gone, and that structural drying has been successful and has not created further problems.

There also needs to be an assessment of whatever cleaning tasks, such as HEPA vacuuming, microfiber damp wiping, use of low grade disinfectants or vinegars, and how effective this has been at actually cleaning surfaces and porous and semi-porous items as well. And then there needs to be a careful look at what methods have been used to analyze the air and/or surfaces.

So, what do the standards organizations say about this? Well, I've talked before about the ANSI S500-2015, and we're going to be looking at a particular section of this, which is section 13.4.4. And the ANSI standard, this is specific for water damage restoration, and I'm going to highlight some important statements embodied in section 13.4.4, which state that a PRV needs to occur when the following elevated risk factors are present. And an independent environmental professional, called an IEP, should be retained by at least one of the stakeholders in order to examine the property. And they're going to be examining the property to assess whether or not some of those occupants have expressed a need to identify a suspected contaminant.

So these are the criteria that need to be considered where contaminants like mould spores, or fragments, or sub-micron cell wall debris from microbiological unwanted growth within the property have been aerosolized. And the key word within 13.4.4, when contaminants are believed to have been aerosolized, because so many problems in remediation occur due to cross contamination. And where there is a need to determine that the water actually contained contamination. And this is particularly important where there are allegations of sewage being the dominant water which caused concerns.

However, we can now have a look at the companion standard, which is the S520, and again the S520 focuses specifically on mould. This is the after effect of the water in the S500, and under section 15 of this standard they have similar but slightly differently worded criteria. They state that a post remediation verification can include both subjective and objective criteria, and examples of subjective criteria include, but are not limited to, visual inspection and odor detection and characterization.

Objective criteria can include, but are not limited to, moisture mapping, the visual inspection, estimates of temperature or indoor relative humidity, and again the key word in this sentence is environmental sampling. And this is where the quantitative measurements occur, such as viable Petri plates, viable surface contact plates, tape lifts, spore traps, and maybe even other swab type tests.

As well, the S520 states that the post remediation verification for the client is a measure of assurance that due to the sampling, testing, and analysis limitations that are inherent to a multi person job in the built environment, that the structure and systems and contents, that is the elements that require remediation, have been returned to a condition one condition.

Now what is a condition one? Well condition one is normal fungal ecology, and this is defined as an indoor environment that may well have settled mould spores, fungal fragments, traces or actual growth whose identity, location and quantity are reflective of a normal fungal ecology. So in a sense we need an estimate of what is normal, and what has been successfully remediated. And it is recommended that the criteria used to establish this change between the before condition and the after condition are going to be well documented in the post remediation verification.

Now, beyond the S500 and the S520, there is a new works document which has been posted on the ANSI standards webpage, and this is entitled New Guide for Post Remediation Verification Following a Fungal Remediation Project. And this is a very interesting document, because it is going to provide additional guidance for all stakeholders involved in mould remediation and water damage restoration, to ensure that there is a more objective set of criteria used in applying and implementing practical post remediation verifications at your property.

Now, I want to spend the next few minutes talking about what a post remediation verification report should include. And essentially this is a risk assessment document, and so therefore there does need to be a combination of both qualitative and quantitative information, because the aim of this is to determine the probability of an adverse effect on human health through exposure.

And this needs to include an assessment of not just the actual known impacts of the water damage, but the potential presence of hazardous materials and pollutants. This is particularly important because you don't want to be in a situation where mould remediation has just covered the four walls and ceilings and floors. What about the voids, or what about the ceiling cavity? So if there's been a top down water event, it's not sufficient to simply remediate inside the room. You need to focus on all building elements, and really it needs to be approached strategically.

And so this is the whole point of including this sentence about potential presence of hazardous materials or pollutants. So from my perspective, your best case scenario is that you will have very similar or same-same ingoing and outgoing data sets, making it very easy to compare and contrast what was present before remediation to what has resulted after remediation.

And sometimes this is not always possible, because there is a gray area regarding what should or shouldn't be included in this PRV. But certainly for high risk groups, or those who have put their hand up to their insurance assessor and stated that, "We need to know before remediation occurs what our levels are." In those circumstances, it's a great idea if the data sets match as closely as possible before and after.

And this is really important, and this leads me on to the next point that I want to make, that the post remediation verification needs to be a legitimate document. It needs to not contain obvious bias. And what I mean by bias is that again, if there's been a top down water damage event, through the roof for example, and if there is a failure to contain any information regarding the roof void, I would say that the post remediation verification has overlooked testing something which is a very significant area of a home that might need remediation.

And so there are lots of examples of this, and in fact some years ago I was brought in to do a post remediation verification on a property, and the remediators asked me to sign off on the remediation of the garage before they even began on the main part of the home. And their explanation for why they wanted me to do a post remediation verification in an incremental fashion, was that they wanted to prove to the insurer, and also to the owner, that they do a very good job, and they wanted to just make sure that they had some ticks on the ingoing.

And in any case they weren't very happy when I said that that's not a good idea, because in your scope of works you're planning on using the garage as the location for decontaminating a lot of the porous and semi-porous personal contents from in this home. So again you want your PRV not to include sample bias, and it would be great if the reports compared like with like, because you want a true and fair estimate of the before remediation and the after remediation back to normal results. So in any case, I would like to close out by playing you a video.

Hello, my name is Dr. Cameron Jones from Biological Health Services, and behind me is a spore trap apparatus. I'm using these spore traps in order to do an indoor air quality and mould inspection. The reason I'm doing that is that the purchasers of this new property are going through the process of extensively stripping it out and gutting it. You might be wondering why they are doing this.

Well, the wife has unfortunately been diagnosed with multiple sclerosis, and her integrative medical practitioner does not want to see her move into a property that has a known or a suspect water damage or mould problem. And I'm going to take you into the area which has just been stripped out, which is the bathroom area, and they found a lot of mould here. So they've stripped this out, and the process of restoring this property is currently underway. Now this is really important that companies like ours become involved in these cases, because we need to make sure that the reinstatement of the property doesn't cover up known problem areas.

For example, a lot of this wall insulation could easily have become wet, and there's evidence of moisture ingress through the roof. And so obviously that needs to get stripped out now, rather than just resheeting it with fresh plasterboard. So the point of this video is to emphasize that when you don't know what the water damage history is on a property, and when there is an immune compromised status of one of the family members, it's better to be safe than sorry. And that may entail extensive strip out in order to get access to remediate the property. Bye for now.

So in conclusion, post remediation verification is the test that you want your home to pass. In any case, my name is Dr. Cameron Jones. If you've got any questions, post them in the comments below. I'll be happy to answer them, and bye for this week. See you next Thursday.

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Dr. Cameron Jones

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