 extension engineer at North Dakota State University, and we want to go through a little bit on using moisture meters to determine when it's safe to rebuild in your flooded home. And it's important for us first to remember that using that moisture meter is not the first step. We need to do the flood cleanup, we need to open the structure and dry it out, and then once it is dry and we're considering rebuilding, that's when we use our moisture meter. And so that period of waiting is very, very critical and important. When we're looking at using our moisture meter, it's important to remember what we're measuring. The moisture meter is determining the moisture content of the wood or giving us a relative measurement of the moisture content of other materials. It's not measuring mold growth. Mold growth is going to occur in wet materials, but this meter is strictly looking at moisture content and not at mold growth. To do mold testing, you need to have it trained professional, collecting samples, doing an analysis that is very expensive, and generally that's not required or recommended. If you see mold, smell mold, you need to use the normal steps that are covered in the NDSU Extension Service, flood recovery information or other appropriate information to do that cleanup and removal. So what we're going to be looking at today is the moisture meter itself. In the NDSU Extension Service has moisture meters available in our county offices that you can use, and we're going to go through the steps of using that moisture meter. The unit that we have that we're going to be using is just a little moisture meter made by a protometer that has pin probes on the end. With the meter, this type of meter, you just turn the meter on and it indicates the moisture content on a dial or scale on the meter. If this is going to be our home or our wall cavities that we're measuring the moisture content in, what we do is physically push the probe into that wood and measure then that moisture content. This is a model of a home and it's very dry and it indicates that we've got moisture contents of less than 60%, which is what we would expect in a dry home. Now for our demonstration purposes, we're going to show using this meter in a variety of different ways on different products. It's intended for measuring moisture content of wood and so what I have done is to put, soak some wood in water to obtain the higher moisture contents that we would typically see in a flooded environment. And so I have here a piece of wood that has been soaking and again, what we would do is just take and push that probe into the surface and measure what that moisture content is. And if it has been in a very damp environment, what we would expect is that moisture meter will be in excess of 20% moisture as is shown on this scale. If we're at moisture contents over 20%, that is wet enough that we would see decay occurring in that wood and so that indicates that we need to leave that wall cavity open, continue drying until that wood moisture content gets lower. Now in this sample of wood, it's not a uniform moisture content so if we go to this other location, that ends up between 16% and about 19% moisture. That falls within the yellow band in this meter indicating that it is in that warning zone or danger zone, not wet enough for decay, but it is enough moisture that if we were to enclose the wall cavity, we would end up with mold growth occurring likely on materials in that wall cavity. It's important that we don't just go by looks or feel. We might have a piece of wood that looks dry, maybe even feels like it's dry, but when we actually do the moisture check on it, we'll find that there's a lot of moisture in that wood, so it is very important to be actually checking that moisture content. Now if we're under that moisture content, as I was showing here earlier, then we're below that 15% moisture, that's where we would want the wall cavity to be. When we have air dried down below 15% moisture, that would indicate that we're dry enough. Now this drying may take weeks for it to happen, and so it's not something that we would expect to occur in just a couple days. This meter can also be used on other materials. For example, if you have a sheet of drywall or sheet rock, we would do the same thing, push the probe into that, and this is indicating about 14% moisture. This is a relative reading. With wood, we're going to get an exact reading. It'll tell us 15% moisture. This we should consider a relative reading, meaning that it is within the range that's a green zone and would be safe for use in our construction. If it was into that red zone, that would indicate that it is wet. Another feature of these meters is that we have an external probe that allows us to get into places that might be difficult to reach. We just plug that probe in. It has pins on the end, electrode pins just like we would have on the end of the meter, and now we can go in and reach spots that we might not be able to easily reach with our meter pushing it in directly. It's very simple to use, but it'll give us very important information. It tells us whether that structure is adequately dried for rebuilding. We don't want to be enclosing the wall cavity or we'll end up with mold growth, and even though it's within the wall cavity, we still have air exchange occurring that brings that moisture or that moldy environment into the living space. So I would encourage you to check out one of these moisture meters, either from the NDSU Extension Service County offices or your local office, or they might be available through form a contractor or someone else. If you're having someone else do the work for you, I'd encourage you to make sure that they're checking the moisture content of those building materials to make sure they're dry before that wall cavity is closed.