AASHTO re:source Q & A Podcast

What's Going on with ASTM D2434?

February 21, 2023 Greg Uherek, Program Manager of Business Development & Technical Services, AASHTO resource Season 3 Episode 41
What's Going on with ASTM D2434?
AASHTO re:source Q & A Podcast
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AASHTO re:source Q & A Podcast
What's Going on with ASTM D2434?
Feb 21, 2023 Season 3 Episode 41
Greg Uherek, Program Manager of Business Development & Technical Services, AASHTO resource

 Greg Uherek joins us to discuss an unusual situation with ASTM D2434: Standard Test Methods for Measurement of Hydraulic Conductivity of Coarse-Grained Soils. 


Show Notes Transcript

 Greg Uherek joins us to discuss an unusual situation with ASTM D2434: Standard Test Methods for Measurement of Hydraulic Conductivity of Coarse-Grained Soils. 


AASHTO re:source Q&A Podcast Transcript

Season 3, Episode 41: What's Going on with ASTM D2434?

Recorded: February 9, 2023

Released: February 21, 2023 

Hosts: Brian Jonson, AASHTO Accreditation Program Manager; Kim Swanson, Communications Manager, AASHTO re:source 

Guests: Greg Uherek, Program Manager of Business Development & Technical Services

Note: Please reference AASHTO re:source and AASHTO Accreditation Program policies and procedures online for official guidance on this, and other topics. 

Transcription is auto-generated. 

[Theme music fades in.] 

00:00:02 ANNOUNCER: Welcome to AASHTO resource Q & A. We're taking time to discuss construction materials, testing, and inspection with people in the know from exploring testing problems and solutions to laboratory best practices and quality management, we're covering topics important to you. Now here our host, Brian Johnson.

00:00:21 BRIAN: Welcome to AASHTO resource Q & A. I'm Brian Johnson. 

00:00:24 KIM: And I'm Kim Swanson. And we have a guest today that I think, and correct me if I'm wrong, this is his first time appearing, which surprises me, is it not? 

00:00:33 GREG: No, Kim, it's not. I actually appeared in an earlier podcast on I think direct shear. 

00:00:41 KIM: Oh well. 

00:00:43 KIM: Brian, why don't you introduce our mystery guest then? 

00:00:45 BRIAN: Our guest today is Greg Uherek, the Director of Business Development and Technical Services that no director manager of? Manager of Business Development and technical services. 

00:01:02 GREG: That is correct. But I I prefer the director title. Even though it's not accurate, it is the manager. 

00:01:09 BRIAN: Yeah, I I think. You should have your own title that is just Greg. You are The Greg. 

00:01:15 GREG: Yes, that would be the most preferred. 

00:01:19 BRIAN: So, Greg, is a legendary AAASHTO resource employee. If you work in ASTM standards development especially in D8. So, on rock, you probably have met Greg before. He has certainly served in different roles within Ashton Resource over the years and has always been a great source of information for me and others, especially as it pertains to soil and rock. So, I've invited him to join us today to talk about an issue that we're wrestling with now. One thing I want to make clear to our listeners on this one is we are going to be talking about a problem, but we are not going to be giving you any solutions. This is more of us letting you know what's happening, because if you are somebody who runs this test, you may have wondered about some communication you have received from us. Or you may have looked at this standard and wondered what is going on so. We want to just tell you the background information, because it's not going to be well known. 

00:02:19 GREG: Yeah, Brian, that's accurate, we do have some conclusions, but we're still trying to get to the bottom of some of the technical issues with this so. 

00:02:27 BRIAN: The standard in question that we're talking about today is ASTM D2434, permeability of granular soils. Before we get too deep into this, Greg, you want to give us just a quick synopsis of what that test is?  This test essentially measures the hydraulic conductivity. The of course, materials primarily used down to, I think it's 10 to the minus 7th hydraulic conductivity K values. It is granular materials, sands, silty materials are primarily tested with this method. There's another method for finer materials and that's. ASTM D508 four 5084. And that is essentially the hydraulic conductivity for fine grained clay particles that uses some different equipment, a little more involved test, but our main issue with this method, Brian, was that last year ASTM had updated the method. And essentially did a really major revision to it, and I think they were trying to include and expand the types of apparatus. This that you could use for this method and sort of open up the field to other procedural approaches to obtaining the hydraulic conductivity prior to the release of the 2022 version there was method A that was specified for both AASHTO T215. 

00:04:03 GREG: Which is AASHTO’s permeability test. And ASTM D2434 and they were essentially identical. Both of them had a diagram of a permeameter. That was really the same piece of apparatus that was used for both methods. One of the changes made in the new version of 2434 was that they eliminated that diagram. And replaced it with kind of a general-purpose generic looking diagram and really changed a lot of the procedural steps as well. And some of it was just a sort of they became more generic in their approach to some of the steps in the method. So, suffice it to say this kind of created a lot of questions on our end and is one of the reasons we're doing this podcast to sort of let you know where we're at with it. And where we see it going in the future in terms. On site assessments. 

00:05:07 BRIAN: I'd like to back up a little bit and when we talk about this test method, can you explain what happens in this test just so people can get a visual understanding of what this test is beyond hydraulic conductivity and permeability, you don't have to get too detailed about what the apparatus. What's like? But just what is this test doing? What do you? What's the technician doing with the material and what's the outcome? OK. So essentially, you're taking material. Still, you know the permeameter is the vessel that's used and there are different versions of it. It can be a solid walled device, or it can be flexible walled. Both of those are allowable in this new method, so we're through into a a vessel of some sort. We're trying to. To compact it to some degree, to represent what we might see in a natural setting in the field, and that's why we're running the test. 

00:06:05 GREG: We want to know what happens when this in place material is subjected to moisture. How quickly does water pass through that material? And in some cases, you want water to pass very quickly through material. That's why we use granular materials under pavements for exams. Simple in some cases you don't want either very little or no water to pass through that material. An example of that would be using like a clay liner under a landfill so that landfill was subjected to the weather. And what you don't want is water going through that. Landfill material passing through the soil underneath it and going into the water table so you can compact and place a clay liner that it's essentially a fine grained material that holds that water and keeps it from. Being dissipated into the soil underneath it. 

00:07:03 BRIAN: Right, but this one is for the coarse. The coarse. They're like this, the sandy materials that you want to see flow. 

00:07:11 GREG: Right. 

00:07:11 BRIAN: So you describe you got a vessel, so a vessel, imagine like a glass or the fiberglass container you can see through it, right? And the technician? Takes that sandy material and they put it in the container can you? Can you go through that process? 

00:07:27 GREG: Essentially, you put it in a container at the bottom of the. Container there's a. Filter disk. There's one placed on top as well. You're essentially want to pass water through that sample and. Time the calculate the amount of time it takes to go a certain distance. Typically, there's a large tank of water that's above the height of the vessel with the material in it, and you could adjust the height of that up or down to create a different head pressure on the material and you typically will run three trials at different heights. And you simply just once you open a valve, that water is free to flow into the material. And the water that comes out the bottom of the sample is captured, and the volume is calculated. And so you can calculate the amount that flowed over a certain period of time. And that's how you come up with your K value, which is typically, and I think meters per second. 

00:08:31 BRIAN: Thank you. I was, I was trying to think something that was easy to understand, and I think that that does it and it and I was trying to think like from a practical perspective if you don't though you know head pressure think about water towers like and water pressure. So if you live in a flat area, you may have a water tower in your town where you've got all this water in this huge tank and the flow of that water and gravity helps create pressure in the lines that gives you a nice powerful shower head that can give you a good shower or whatever. So that's the concept of head pressure anyway. 

00:09:11 KIM: So fun fact I learned very recently in the last five years, what water towers did? I thought it was just to hold water. So thank you sharing that knowledge Brian for everybody. But yeah, for most of my life, I thought they just stored water and it was had nothing to do with pressure. I was misinformed. But that was an aside for. The topic at hand when we were discussing the standard and that we wanted to do an episode on this, I. Googled it because. I don't know what you're talking about and I see that ASTM D2434 again was updated in April of 2022 and we are now into 2023. So, I'm curious about kind of the process that led up to you know, after it was released to now that we're noticing. Or felt the need to share that there's a problem. What was that process to get to where? We are here recording this episode. 

00:10:06 GREG: So, the method was approved, it was validated and finally approved in April of 2022, as you said. We don't have a lot of laboratories that we accredit for this test method. I think in total there's around 70 or 75 labs in the country. So it was a while before we kind of got caught up with those changes and realized the significance of them. And I think it occurred. Initially, when an assessor visited the lab and they were running this test. And we started to look at some of the changes and quickly realized that they were significant and that we had maybe needed to pull back just a little bit and reevaluate if that method was how close it was still with ash, toes version and reevaluate the technical requirements. So that we could. Give the proper guidance to our staff. 

00:11:01 GREG: So sometime in I think the third quarter of last year, maybe September or October, I believe we informed laboratories that were credited for this test or I think all of our customers that. For the time. Being we were. Going to not going to perform the. Assessment for D2434 until we were able to work through some of these technical questions. You know, we want to make sure if we're in a lab evaluating testing labs capable. We want to ensure that the assessor that's there is is able to properly evaluate the equipment and fully understands the procedural changes before we perform an evaluation of course. So at that point, we kind of pulled back. I had some discussions with some of the folks at ASTM, specifically the subcommittee. That was responsible for developing this revised method, and one of the things that came out of those conversations was. 

00:12:02 GREG: That the new requirements and the new diagrams were not meant or intended in any way to prohibit the use of the equipment that was previously specified. Because if you look at the diagrams, they're very, very different and some of the requirements for the permeameter itself. Their goal was clearly to expand the requirements to allow for different types of devices to be used. So one of the big conclusions from this was that. That the equipment most all the labs have been using and that conformed previously to AASHTO ASTM, that equipment is still in spec. It should not be an issue as far as we can tell at this point. There are some other types of equipment that are have been added to the standard that we're still. Sort of evaluating. And I guess I'll just add now, ASTM has a method A and a method B. 

00:13:03 GREG: So method A is rigid wall permeameter. And that means the wall of this vessel was solid. It's typically metal. It doesn't have to be metal. It could be, you know, plexiglass or something, but it's not going to flex. And there's two types of those. So they have two methods, one is. A single ring permeameter and the other is a dual ring permeameter. The use of a door ring permeameter is new in the method, so that's one of the new requirements that is not covered or discussed in the ash toe method. But essentially a dual ring Permeameter has a ring inside the base plate of the vessel, and that ring is used to separate the flow of water on the outer portion of that vessel from the inner portion. And the reason you want to separate it in some cases. Is that? Certain course materials are going to give you sort of a turbulent flow on the outer portion of the mold. So as that there are voids along the side of the mold, and again the mold doesn't flex, so you're kind of stuck with whatever voids when you put the material in that vessel and it can give you some really.  Erroneous results. So the use of a dual ring permeameter is to hopefully resolve some of those issues with certain material types. 

00:14:30 KIM: OK, so my understanding. Of what you've just said is that when the they made changes to the standard. In 2022. And the intent was to broaden the types of equipment that could be used. So it wasn't so limiting. However, a possible unintended consequence of that is that they made changes. That at first looked like it was kind of limiting, but you they weren't what was previously accepted was no longer accepted, but with other discussions since then that you've kind. Of realize that they are acceptable, but it is just not necessarily clear about that. 

00:15:09 BRIAN: That that's exactly what I thought when we looked at this. So we had an assessor that performed an assessment using the worksheets that have been updated to the new language of 2434 and the conclusion the assessor drew is that this did not, in fact describe the existing equipment that we had always seen, so that that raised the question with us and we like we got. To figure this out.  So then I went back and looked at at the ballots to see how this happened. Like, how did we get such a drastic change? To the method because when I looked at it, it no longer defined the equipment that had existed prior and was approved prior and not just that the graphics or the figures did not show that apparatus anymore. So when I read it, it was written generally enough that I could see.  Like after looking at it again after getting after I got an explanation back from the committee. 

00:16:05 BRIAN: I can kind of see. How it doesn't outlaw the old equipment, but to me it still doesn't really clearly define it either. So, I think there's still a an improvement that needs to be made. But basically like when I was looking into this, I went back and looked at the ballots and there was some confusion. There was some unusual balloting that I saw that raised the concern with me. And I voiced that concern, ASTM. So, the way it. Worked is they're working on a new standard. To replace 2434, that would be more broad I guess, and they worked on it for a while, worked on it for a while and at some point they decided that instead of doing that, they would ballot this as a change to 2434. So all this new standard language, but what was balloted was a track. Changes version of the new standard as a replacement to 2434 as we formerly knew it. 

00:17:03 BRIAN: And as a voter, when I see that I look at the ballot, I'm not doing a cross comparison of the old version to the new version because typically what you see is the old version with track changes on it with all the proposed changes. But if I when I look at the ballot and I see this new standard that looks like it's the old standard with track changes. I'm just looking at those changes and saying OK, well, that's not such a big deal. And I might say it's OK not knowing that it did. It wasn't actually the old standard. So in my view that was. The problem D18 already had this understanding that this is what was happening. Everybody was on board with it, so it wasn't a big deal to them. And if I was a real like expert on 2434, I wouldn't have had that question. I would have known it was a new standard, but you know, like I get a lot of ballots. I am not an expert on every standard test method that we look at and every practice, believe it or not, the hundreds of them that there are, so something like that could certainly slip by somebody like me without batting an eye over it. 

00:18:11 BRIAN: So like, I thought that wasn't great. I also think that it it wasn't great that they removed the old figure that clearly showed the apparatus that was always acceptable and was intended to still be acceptable. So like in trying to generalize it, it raised some doubt in our mind whether we should be able to continue to accredit for dead 2434. Without expecting to see new apparatus at the laboratory. So we did put the brakes on it for a couple labs that had gone through the process while we were. Figuring that out. And now that we know that it wasn't really intended to be changed, that accreditation can continue. We've kind of come full circle now that we've figured out what was going on. Like I said, still some work needs to be done on the standard we believe. To make it more clear, but there shouldn't be a disruption to the accreditation for those labs that had 2434 before based on what we know. 

00:19:09 KIM: Thank you for that clarification and a couple of things. Know I was. Thinking about and so perhaps our listeners were thinking about during this conversation. As well is. That I know we have a process for updating the assessor worksheets and the tools that we use internally when standards are updated. So in my first thought was then. How did? This get this. Far, you know, like be how did we not notice this sooner in that process. But I do think that you kind of touched on that already, but is there anything that you? Want to expand on that? 

00:19:40 BRIAN: We have people on staff who do that right, so we'll have a designated person and an assessor more than likely who will review the changes, update the worksheets that we use to reflect the new language and at the time that that happened, it may have been clear to them that the old apparatus is just fine. You know, like that's entirely possible. I do not know the answer to that question, but obviously when it got in the field and somebody was actually trying to follow through on whatever that apparatus was, it was presented. Things weren't lining up, and that caused the question. So I think it was probably that or it's possible that that person wasn't really that familiar with the test who was updating the worksheets. They were just. Seeing the the text. Based on what they saw and you know not everybody has expertise on our staff on every single test method. So that could have happened too. It's an unusual situation that's like that. I think that's one thing I really want to make clear. Typically things aren't valid in this way and we probably should have noticed. That this happened, but for some reason or another we didn't. 

00:20:51 GREG: I completely agree with what you just said and also kind of reiterate. If everyone does the.  Best they can do with the ballots. But you're inundated with ballots, and sometimes they come in big bunches. You don't have unlimited time to review them. And I think. A lot of folks, if you're somewhat familiar with the test, you may, you know, quickly review the redlined version and as long as nothing seems really. You know, out of out.  Of line you just you know you. Vote affirmative and move on. And I think that's kind of what what may. Have happened with this standard. Because frankly, I mean, and this is just my opinion, but there's a method B that was written into this test method. And it's clearly written, but it's combined with requirements for method A. So when you read the standard as a whole, it's really confusing. : It really is. You know, and had. I been at the subcommittee meeting I, you know, I haven't attended this one for a while in person. 

00:21:53 GREG: You know, that would have been something I suggest. I would have. Suggested probably that take this new method and just create a totally separate test method. Don't try to add to the existing method. And it ended up complicating a lot of things. 

00:22:08 BRIAN: I wonder about that too. If the way things worked out with the Hydrometer. I mean we have other another episode on the Hydrometer that was an exercise that was. It was. It was unusual in that there was a new standard to or two new standards to replace an old standard, and that old standard was really lacking in certain details. But the committee decided to to split it up and make 2 new standards and thought, OK, well, people would just won't use this old one anymore. 

00:22:37 KIM: Right. 

00:22:38 BRIAN: We'll sunset it. But that's just not, you know, you do your best, you know. And you come up with these plans and you think everything's going to work out but you. Can't control everything. So little did they know a lot of this best valuing agencies really like the old version. That was a little incomplete and are going to continue to require it. And we just, we actually just looked at the data yesterday and we've got over 800. In our program that are accredited for that old version that was sunset in in the committee, thought would just disappear, but it didn't happen that way. And I wonder if that experience led to the decision not to make a new standard in this case. Maybe it had nothing to do with it, but it makes me wonder if that might have been a thought in the leadership's mind. 

00:23:21 GREG: It could have been Brian. I think that's a good possibility.  I know that the technical contact had been working on this for five or six years, I believe. I think it went through a number of iterations with the ballot and yeah, something that happens too is. Just sometimes when things are rebalanced 3-4 or five times, if you previously reviewed the ballot and voted affirmative or negative in some cases you see it again and you tend not to unfortunately go through it in the same detail that that maybe you did the first time. And so you end up with something that maybe there are still some questions and things that can be clarified.  And one of the things we hope to do is give some feedback to the subcommittee as we go forward and evaluating this in the labs, seeing what kind of questions the labs have, see what their struggles are with, you know, understanding the requirements perhaps and then pass that on to the subcommittee and hopefully, you know, improve the standard where it needs. 

00:24:29 KIM: So because this is an ASTM standard, I believe so. Correct me if I'm wrong that they can be updated and revalidated at any time. It is not like the Astro standards, which are only published and updated. Once a year, so the ASTM can have in theory multiple versions of a you know ASTM D2434-22, ABC or whatever it goes after that. So there isn't necessarily the restraint if there are.  Changes needed. It can be balloted sooner rather than later if needed correct. 

00:25:10 GREG: That's right, Kim. So, you know, if we come up with some recommendations and get them off to the subcommittee, you know, as quickly as they can make the changes to the standard. And turn it around and and put a ballot out. It can be done and it's actually happened with different standards. There's been two or three updates during the course of a single calendar year. That's not ideal, but if if the end game is to make some improvements or fix things that are kind of broken or clarify them, you know. It's it's leading to a better standard in the. But yeah, you you sort of seek to make changes on a quarterly basis to a standard, it's tough for. People to keep. GREG: Up you. Know with the changes. 

00:25:54 BRIAN: And I I'd like to see the inclusion of that old diagram or a version of that old diagram, just to make, or the figure just to make. It clear to people that that was intentionally. We supposed to conform to the requirements of the. Then in the new the new language that was you should not make it so that that's been outlawed, because that was not the intent. From what we heard back from D18. 

00:26:19 KIM: D18 is the the subcommittee that this standard falls on, correct in the ASTM structure. 

00:26:25 GREG: The ceremony, Kim, I think. Is D18 04. 

00:26:27 KIM: Committee or force. But it's the head. 

00:26:29 GREG: Is it some? 

00:26:29 KIM: OK, you're just throwing out jargon, if you? Weren't familiar. I just wanted to stand by with. 

00:26:34 BRIAN: I love that you use the word jargon because one of the 18's favorite things to talk about is jargon. So yeah, the 1818 is a is a committee. 

00:26:34 KIM: That one. 

00:26:43 BRIAN: And like Greg said, the individual subcommittee was what? 

00:26:47 GREG: I think it's O four D 1804. 

00:26:50 BRIAN: You've got the subcommittee they vote on, so like that is part of the process. The subcommittee votes on these changes. If they approve it, then it goes up to committee level and then the whole committee has to approve it and then it becomes a standard. 

00:27:03 KIM: Gotcha. And you talked. Briefly as well, you mentioned AASHTO T215. If I recall correctly that that is was the equivalent to this. Is there any changes in the pipeline for that or how does that work now that they are not necessarily the same? 

00:27:24 GREG: Well, as far as I know, there's no changes being proposed for ballot in the ashtone verse. There are two methods in the Ashton version, method A and method B. Method A is as far as I can tell, pretty much equivalent, and that's the single wall permeameter to the method a that's written into the new ASTM Method 2434, again under method A, they do have. Two Permeameter is listed. One is the single and one is the dual. The dual ring permeameter is not recognized in Ash totie 215. But it's a new alternate method in the ASTM. But as far as the solid wall permeameter it is, I believe the same in AASHTO and ASTM so. I do think that the old diagram that Brian mentioned should and could be easily added back into the ATM method as an alternative diagram for that piece of apparatus that you know clearly depicts what manufacturers have been selling. To labs and what almost all. Of the labs use. So when they changed the diagram and removed some of the like the spring that's on the top of it is gone and some of the other pipettes and the and the presentation of it is just completely generic.  It it opens up a lot of questions. 

00:28:56 KIM: So is this one of the instances where they tried to be kind of more inclusive by being vaguer, and it turned out just to be more confusing. 

00:29:03 GREG: I think so, Kim, I think that's what happened. I wasn't present at those meetings. That's where I'm bled to believe they were thinking. Let's not limit this as long as they have these essential components to the permeameter, it'll meet the requirements for the method. 

00:29:21 BRIAN: That is a challenge for standards development is you want to be really specific enough so that somebody knows what they're supposed to do, what they're supposed to buy. Manufacturers know how to make it. Or what they should be making, but when you you you know, if you just say a vessel like that could be anything, right. Like, it's really a challenge for the the standards developer to be specific enough that someone can look at something and say yes, that is what that is. So you don't want to be so vague and broad that. Anybody could make it out of anything like that. I don't think that's really what you want. I think you want to see standardized equipment like when you see it. You're like, hey, that's what that is. I know, I know what that is. It's defined clearly in here. I have seen it in various committees where it's so broad that it's hard to tell what you're even looking for. 

00:30:12 BRIAN: So Kim mentioned jargon earlier and I didn't really. I touched on that, but there is actually a a policy in D18 where they do not like to see jargon in their standards. And I think it's a really good idea that they do that because it's so pervasive in every industry for people to use.  Terms that are not widely understood or they're just special words that only the committee members use, or only people who are on the inside use, and you really want to not have those in standards at all. If you can avoid it. So that's it. I I have to hand it to D A-Team. But I I do laugh every time I hear somebody mention jargon in D A-Team because they they do. Talk about it quite a bit. 

00:30:54 GREG: We do.  It's one of our favorite topics. But again, as you said, it is it, it's a good topic. So we like to be clear as we can. One last thing and I and I'll just mention this because it was part of the changes. Method B is the flex wall permeameter and so this typically would use like a flexible membrane, very similar to which used for triax test or for D5084, which is the clay permeability we talked about earlier. And you know one thing that. Because it's it, it eliminates the side wall leakage effects because now you have instead of a rigid wall where water is kind of becoming turbulent and flowing along that outer wall, that flexible membrane is kind of pulled tight against the parts. So now you don't have these large voids and you're really removing that leakage effect. 

00:31:53 GREG: Typically with method B they would then apply a confining stress to recreate field conditions, and that also measure pore pressure. So, it's quite a bit more complicated I have not. Encountered any labs that run this version? Or that have. Tested permeation this way so I'm curious to see how many labs may really be performing it now that it's sort of in a standard and covered in some detail. Currently though, we are not offering accreditation for Method B, it's method A only. Is that correct Brian? 

00:32:29 BRIAN: We are not specifically stating that they are performing method A or method B currently. 

00:32:36 GREG: And and that's maybe something we should look at doing, I just don't know if there's going to be many, if any labs that want to or that do perform method B I'm just not sure. I think it's used in. Research quite a bit. But typically that's not going to be the labs that are seeking accreditation for the method. But I think right now we it's possible that we may just evaluate method a in the labs moving forward. 

00:33:04 KIM: Question which is topic adjacent with Method A's and Method B's and any standard is that? Saying that you're going to get the equivalent results when you run method A and you'll get the same results or equivalent results.  Or is it just a different way and you're going to get different numbers and you do different things with those results? 

00:33:28 GREG: Yes, great question, Kim. You know it can go both ways in some cases. Method A&B really are going to yield very similar results. But in other cases, because it's a, it's really a different method and the results aren't going to be similar. So it's very important to recognize which method was performed when that test was run, and sometimes there are differences in equipment.  Yeah, most of the standards have some type of a precision statement sometimes. It is recognized when a different procedure is. Certainly in this case with the perm, the difference between a flex wall and the rigid wall, those results aren't going to be the same. They're just not. Going to be so they're two very different test methods. 

00:34:16 KIM: And then you the. Engineers, or whoever uses the results, do something. Very different with those. Results for method A and method B. 

00:34:25 GREG: I don't know if they do something different, but they should know which method is being performed so they can compare apples to apples. 

00:34:33 BRIAN: I don't love method AB. Whatever like I really like when it's standard is is has a one. One way of doing things where possible because it makes it easier for comparison’s sake. I also don't like a proliferation of state or local methods that are kind of like, but not exactly the same as a standard test method, because then you know we look at our proficiency sample program and we are having all these laboratories test them and we're making an assumption that they're running. A certain standard test method, but if there are a ton of these different versions out there that people would run in their localities. And they're running that because they run it all the time and they and they don't run the AASHTO or ASTM, whichever has been specified then all of a sudden that kind of messes the data up or has a potential for messing the data up. And then there are expectations for repeatability of test results that is not accurate. : So I really think it's better if you have one way to do things. 

00:35:40 GREG: I agree. I agree, Brian. And and this this one is a good example where you're talking about method A and method B used completely different equipment. It's completely different and the procedure is different. But what they did is they tried to combine both procedures into one section. So that say if you're using method B, do XYZ. If it's method A instead, do it this way and you I think it would have been better if they just separated method A&B completely. But they they combined it and and the text and that just added to the confusion I think. 

00:36:23 KIM: What are the? 

00:36:23 BRIAN: Next steps for internally we need to make sure our staff knows that the old equipment is going to work and I think we've already done that standard development, you know for ASTM like to see them work on this standard. Hopefully get that figure put back in there so or some version of it so that it's really clear to people that that's going to conform for the accreditation program. We already have kind of taken care of that by not taking away anybody's accredited. Because we thought that they weren't in conformance anymore, but we did kind of hold. We we did tell people to kind of hold off, so our responsibilities get back to them and say no, everything's fine. You're OK to continue being accredited based on what you presented, because I think in the cases I think we had two laboratories that were in this situation and I believe they. They did run 215 which is the equivalent of D2434 and and they're they're fine to continue along with their accreditation. So I think we're good there, but I think some work needs to be done on the ASTM side and I think they'll probably be some more communication with them. And you know, luckily we've got Greg in those committee meetings and. And as a sounding board for people so that you can kind of help facilitate that. 

00:37:38 GREG: And also I think we'll need to decide internally if we're going to a credit for method A&B. Or just method A at this time. Anyway, I think there's quite a few questions that surround the method B that we may want to hold off for a short period of time, but we'll we'll have those discussions internally and and make decisions and communicate that. To the laboratories as well. 

00:38:04 BRIAN: Thanks, Greg. I appreciate your time today. Thanks for taking us through. This story. The It's a little it's a little different than what we're used to dealing with, so I hope if you are performing this test that this was of interest to you. If you want to get involved with ASTM to help move this project along, it is very easy. Go to astm.org and find out how to be a member. Join the committee, join the subcommittee and see if you can make some things. 

00:38:30 KIM: And I will stand corrected that Greg was a guest on season one, episode 18 about. Direct share so. 

00:38:37 GREG: I thought so. Thought so. 

00:38:38 KIM: I was. I just. We've done too many. So I stand corrected. So thanks for being a returning guest Greg. 

00:38:44 GREG: Yeah, both. Thanks Brian. Thanks. 

00:38:44 KIM: Thank you. 

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