AASHTO re:source Q & A Podcast

Top Nonconformities for AASHTO T84 and ASTM C128

November 30, 2021 AASHTO resource Season 2 Episode 31
Top Nonconformities for AASHTO T84 and ASTM C128
AASHTO re:source Q & A Podcast
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AASHTO re:source Q & A Podcast
Top Nonconformities for AASHTO T84 and ASTM C128
Nov 30, 2021 Season 2 Episode 31
AASHTO resource

We discuss common nonconformities for the Standard Method of Test for Specific Gravity and Absorption of Fine Aggregate and how to resolve them.

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Show Notes Transcript

We discuss common nonconformities for the Standard Method of Test for Specific Gravity and Absorption of Fine Aggregate and how to resolve them.

Related information:

AASHTO re:source Q&A Podcast Transcript

S2 E31: Top Nonconformities for AASHTO T84 and ASTM C128

Released: November 30, 2021 

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

Guests: Christina Mauri, Laboratory Assessor, AASHTO re:source; Ester Love, Quality Analyst, AASHTO re:source

Note: Please reference the applicable AASHTO and ASTM standards, as well as 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’s our host, Brian Johnson.

00:00:21 BRIAN: Welcome to AASHTO Resource Q&A. I'm Brian Johnson and with me is Kimberly Swanson, producer and Co-host. Hey, Kim.

00:00:29 KIM: Hey, Brian, how you are doing today?

00:00:30 BRIAN: Not too bad. Today we have got another top five nonconformities and corrective actions episode with our recurring guests, Christina Mari and Ester Love. Welcome to the podcast, both of you.

00:00:48 CHRISTINA: Brian, thanks for having us back again.

00:00:49 ESTER: Hello and thanks for having us.

00:00:51 BRIAN: Anytime and hopefully we do a couple more of these in the future too, to get everybody up to speed on what this episode is all about, we are going to take one test method today. We're going to talk about in aggregate test this is fine aggregate specific gravity that's AASHTO T84 and ASTM C128. Two very popular tests in the AASHTO accreditation program world because they are required tests for ASTM C1077, which is a highly coveted test in the industry of concrete and concrete aggregate testing. And we’ll get this out of the way, concrete aggregates are just aggregates used in concrete. That question comes up every once in a while, but anyway, I digress. What we're going to talk about is the top nonconformities and corrective actions. That we experienced it during the assessments and in the follow up. So, somebody put together a list of these and I'm going to ask Christina question right off the bat here.

00:01:55 BRIAN: The top one, not the top one, but the top several because they are redundant in our list that no one can see other than us right now. So, that's probably not too helpful. But the top nonconformity is about the temperature of the contents in the pycnometer.  That's the container that's used in the test.  The temperature was not adjusted to the test temperature after the elimination of air bubbles and before.  The mass was determined that seemed to come up all the time.  Christina, why is that?

00:02:28 CHRISTINA: So, this one happens a lot and it's important because this test method is used to determine specific gravity at a certain temperature, and so if we're not taking the temperature and verifying that it's about 23 degrees C, they're not.  Correction would have to be applied in calculations, which is not what this test method covers, and I think most often people.  My want to assume.  That it's at that temperature because it's near room temp and so they don't verify that with the thermometer or adjust the temperature of the content just because they think hey, close enough, it's room temp.

00:03:01 BRIAN: When laboratories are running this test, are they taking this water from a bath or is it coming out of the tap or why?  Why might they be confident that it's at the room temperature?

00:03:12 CHRISTINA: Generally it should be distilled water, I believe from a jug.  Often I see that's like sitting on the bed.  So in their room, they might assume that that.  Water is already at.  Room temperature.

00:03:24 BRIAN: OK.  That makes sense.  I can see why somebody would get complacent then.  If it's sitting at the same temperature, that if they've already determined it should be, you know, they've determined that's temperature.  Once they agitate it, I could see why they might think.  Oh well, I don't need to do that again, but can that temperature change even in that?

00:03:41 BRIAN: Well, I'll call it a flask.  The test method says pycnometer, but we'll use flask just because people that's a little easier to to see when you're hearing that word, what happens during agitation that might cause that temperature to change from what was put in the container originally.

00:03:57 CHRISTINA: One, if your flask is cold and you add your room temp water to your flask, your water is.  No longer in.  Room temp.  Then you're agitating your flask with your hands, which are not room temp, so you're transferring heat from your hands to.  The last so your temperature is automatically going to increase, but then also just the process vegetation.  So I think that is, yeah, that's something.  That's overlooked a lot.  You're definitely varying the temperature during that agitation process in a couple.  Of different ways.  So definitely need to check that after you eliminate your air bubbles and.  To 23 degrees C and you.  Can do that by, you know, putting it in a water bath or.  Running it under some cold water and taking your temperature.

00:04:40 BRIAN: And now if they don't get it at temperature.  Is there a correction?

00:04:42 CHRISTINA: So, there is a temperature correction, but according to T84 and C128 you should be calculating the specific.  Gravity at 23 degrees.  So when you're taking your final measurements, your mass determinations it needs.  To be at 23 degrees.

00:04:59 BRIAN: So Ester, given that information that we just heard from Christina, what is the laboratory to do to resolve this non conformity?

00:05:08 ESTER: But the lab wanted to resolve something like this.  It is a procedural, since they're not checking, so it would be to retrain their technician on that test method.  If it's something that's continuously happening, they'd want to submit a corrective action report.  So if you want to remind yourself to make sure that you're taking that temperature so it doesn't happen again, or maybe it's the first time it was presented to you.  If you have a data form or a data sheet, you can add taking that temperature to that sheet so that way it's a good reminder to take the temperature or you can put a sign up.  In the lab.  That just says, hey, take the temperature after you agitate the sample.

00:05:49 BRIAN: Yeah, that sounds good. Now the next one, we're going to talk about is also procedural. So that's going to be another similar outcome from Ester's perspective. But Christina, let me ask you about this one.  The nonconformity is in the procedure used to fill the pycnometer water was not added before this sample was introduced as specified, so we're talking about.  Filling up the flask or pycnometer before weighing the sample.  Or before agitating it, how what?  What are we talking about here?

00:06:19 CHRISTINA: Alright, so for this nonconforming, this is discussing the first step of the procedure where it describes how you.  Should add a little bit of water to your pycnometer.  Throughout your scale and then start adding your sample.  And that's just so that there's already water at the bottom of your pick number before you add your.  Sample and that's just to help saturate.  Your sample because.  If you throw 500, you know grams of aggregate into the body of the pycnometer and then try to get water all the way down to the pycnometer. It's going to take a long time.  And a lot Of effort.

00:06:48 BRIAN: One other thing I always thought with that issue is that it's very hard to dry pycnometer with a long neck and a lot of times you have moisture in there anyway.  So it seems like it's good to do the tearing of the of the balance with the water in it before you add the sample so you can get your 500.  Plus or minus whatever is .5 grams. What? What's the tolerance on that?

00:07:12 CHRISTINA: Tolerance on that is 500.  ± 10 grams.

00:07:18 BRIAN: 10 grams.  Geez, that's a lot of variability there.  That's fine though.

00:07:22 ESTER: I also know the water being introduced first helps cut down on dust so you don't lose any of your fine particles also.  I don't know if this is a good analogy to use, but when I've been baking a cake and I put my dry ingredients in first and then I try to add the wet, it takes a lot longer to get those cake clumps out, so it's the same concept if you're using a soil.  When you add your water and afterwards you get a lot of clumping in there that you got to try and smooth out that you.  Can't and a pycnometer with a narrow neck so.  It's good to have the water in first, whether you're baking or testing the fine ag of your specific gravity.

00:07:57 BRIAN: That is a really good analogy.  I actually made a cake yesterday and I was really out of practice.  I did exactly what you just said, though, Ester, where I had all my wet ingredients together into a nice slurry, and then I added my cake batter into it and mixed it up and it mixed up really nicely.  But I'll tell you why I screwed it up.  I pulled it out of the oven and instead of letting it sit for a while, I tried to take it out of the pan.  It was an absolute mess.  It just went it.  It crumbled everywhere it was.  It was a.  It was a very nice consistency of the cake.  I have to say it probably because of exactly what you were talking about, but my impatience to eat the cake really kind of ruined it.  But that did not stop me from putting frosting on it. It looks like a three-year old made.

00:08:50 ESTER: You just crumble the cake all at once then and mix your icing and you make.  Cake pops.

00:08:55 KIM: I was just going to say that and then for the people that that are listening to this so everybody.  Everyone else, while Brian was telling the story, was shaking.  Their head like.  No, don't do that.  Don't take it out right away.  So we knew where it was going before Brian.  So next time and then the next year that you make a cake, just remember the patient part.

00:09:15 BRIAN: I will and it's not going to be too long because I can't put an end to this cake.  Situation like that.  So I'm probably going to do that either tonight or tomorrow night.

00:09:26 ESTER: This all just went way out of hand.

00:09:27 KIM: It did. I'm.

00:09:28 ESTER: It escalated really quickly.  Trying to think of how much.  How much are we keeping?  Of this and how much?  We're not. We're we'll, we'll.

00:09:34 BRIAN: Yeah, we can.  Keep going with analogies.  I think that's I think that's totally fun.

00:09:38 KIM: At least I can.  Partake in that conversation.  What you're actually talking about I have.  No idea so.

00:09:45 BRIAN: All right.  Well, that well, that situation is procedural.  So again, Ester was talking about how people resolve procedural nonconformities already in the first.

x One so with.

00:09:57 KIM: The procedural nonconformities Ester has mentioned just retraining.  How do laboratories know if that's been effective?  Like, how do laboratories show that they've actually retrained somebody for the accreditation?

00:10:12 ESTER: I don't want to answer this one.  Not that I don't.  Know it's just sometimes we accept that just the sentence that says the technician has been retrained on the test method, but I don't want to put that in a podcast because then everyone's just going to send sentences that say.  The technician was retrained, but we would accept that.

00:10:34 BRIAN: Yeah, she's right.  We would.  You know, a first-time offense retraining is appropriate.  What we'd really like to see is an official retraining with a competency evaluation record that would be ideal, but we would accept for a first time issue that's not having other loose ends with it.  We would accept that.  There's a lot of things that are more than just procedural that appear to be procedural, which is why I'm not going to say across the board that that's acceptable because sometimes it's so loaded.  Conformity and that usually causes some frustration from the perspective of the laboratory, when it is a compound issue, and that retraining isn't sufficient.  But yeah, I'd agree with what Ester said, though.  Typically, just a simple retraining is sufficient resolution of that nonconformity.

00:11:28 KIM: Thank you.

00:11:29 BRIAN: All right, third one, I can't wait to hear about this one because I was not familiar with this nonconformity in my years of assessing.  Records were not presented to indicate that a comparison had been made to ensure that the results of mechanical agitation fall within the acceptable limits of manual agitation listed in table one.  Christina, what is this madness? Who's using a mechanical agitation device for C128. I have never seen it. Maybe it's.  Common in a state that I just haven't been.  Into for assessments.  Are you familiar with this nonconformity?

00:12:02 CHRISTINA: I have seen.  This like once or twice, I will see people put their pycnometer filled with sample water onto like the rice vibratory apparatus.  And again, that's perfectly fine as long as you.  Can show that.  That does not degrade your sample, so you do that.  Through a mechanical manual comparison, but.  I rarely see this.  I guess it's not that common, but if you aren't doing it, you would need to do that.  Comparison and I.  Guess that it's not happening as often as.  It should if this.  Is one of the top nonconforming.

00:12:33 BRIAN: Is there any thoughts on?  This one.

00:12:35 ESTER: I agree with Christine.  It's not something that I ever saw as an assessor.  Very often, if you were going to be resolving that, we'd want to see a record showing that comparison, as Christina said, just to make sure and ensure that the sample is not being degraded with the mechanical agitator.

00:12:53 BRIAN: I'm going to kind of answer partially answer my own question as to why this why something like this would be in a.  Standard because what happens sometimes is, especially at a state the Department of Transportation, they're really trying to ensure consistency in the testing from a production facility like a QC, like a quarry laboratory, and then a third-party testing lab like the OR Department of Transportation.  So sometimes they'll put some requirements in the standard.  Like, use a mechanical device and set it for this much time.  Or some way to ensure repeatability of measurement.  But and I don't remember whether it's C 128 or 284 that had this requirement in table one. Do you Christina which standard required this was it   AASHTO, ASTM?

00:13:47 CHRISTINA: So actually both standards.  Require it.  It's in both of the standards and.  It is in table one of both standards.

00:13:54 BRIAN: OK.  So yeah, so a lot of times those things are added just for consistency of application.  But like we said, it doesn't happen a whole lot.  So it must be kind of.  I'm going to guess it's a regional or state.  Specificity situation where they actually are using it because it is a pretty small amount. We're looking at 28 nonconformities like this over in an entire tour, which isn't a whole lot, but it did still make.  The top five.  Next one, we're going to talk about is.  The volume of the pycnometer presented this is specific to the fruit jar.  It's like a canning or like a canning jar.  You know, like one of those ones that you might have, like Pickles or tomatoes or Peppers or anything else.  Ester, what's your favorite thing to pickle?

00:14:48 ESTER: Eggs. 

00:14:50 BRIAN: Yeah, pickled eggs pickled I of course you got to use the bigger container for.  That right because you need the beats.  And the and the.  OK, so the non yeah, the non-conformity is that the volume of the pycnometer presented which was a fruit jar fitted with the pycnometer top cannot be reproduced to ± 100 cubic millimeters. The pycnometer was filled with water to a line.

00:14:58 ESTER: Anyway, back to our pickling jars.

00:15:18 BRIAN: Marked on the jar rather than to the top of the pycnometer.  That happened almost as much as that last one that I wasn't familiar with.  Christina, do you see this one a lot.

00:15:30 CHRISTINA: I have seen this one a handful of times I would. Not say a lot.  But I've definitely seen it in person, and I'm about it's been happening.

00:15:38 BRIAN: OK, so when you write this up at a laboratory, what is the response usually from the technician?

00:15:45 CHRISTINA: Oh, we put a mark on it with a Sharpie, and that's what we.  So that's basically what I hear and I say, OK.  Right.  But is that like repeatable?  Did you get that Mark?  Yeah, so something else.  Sort like that.  Is that is that like a precision mark, you know, or could you eyeball it with your, your sharp or something like that?

00:16:04 BRIAN: Ester, have you seen this on the on the other end of it on when you're looking at corrective actions to address the non-conformities, have you seen this one come up?

00:16:12 ESTER: I actually have not seen this one come up as of yet.  So, while does happen?  It has not happened with me.

00:16:19 BRIAN: You know, if we're talking about repeatable measurements, so what would you consider this?  Would you classify this as a procedural one or something where you'd expect to see some kind of record to resolve the non-conformity?

00:16:31 ESTER: I would classify this as both the procedural and that they didn't know that they needed to calibrate that to a precision mark, and also I'd want to see a record that they did make that change.  So it does need to be calibrated up to and overflowing the pycnometer top just for repeatability.  It's not, as Christina said, you not always accurate to just get it up to that line.  You don't know that you're getting it.  The water filled.  Is it above the line below the line in the middle of the line so.  It's just more consistent to have it at that Pinon meter top that I would want to see procedural and a record for this.

00:17:13 BRIAN: Yeah, now currently R18 requires any volumetric measures to be included in the annual standardization records.  But that I do want to mention that there is going to be a ballot out for R18.  We've got a lot of input from the laboratories in the program about that, that that is not a very popular requirement.  So the ballot is going to include removal of that from the annual list so that it doesn't mean they have.  They don't have to do it anymore, but they wouldn't have to document it.  In the manner that other equipment calibration, standardization and checks are required in the AASHTO R18 tables. So, we'll see what happens when that goes out the ballot though, because that has to get approved by all the DOTs.  So, we'll see what happens, but that'll take us to our last item that we're going to talk about.  And I was surprised.  Well, I guess I kind of screwed up because this is a multi-nonconformity.  So this one came up twice in our list.  So it actually is more common than it should have been #3, but this is related to the SSD condition.  Determination for this test and filling the cone and using the tamper.  So Christina, what goes wrong when people are doing the determination of saturated surface dry condition in fine aggregate testing.

00:18:41 CHRISTINA: Well, a couple of.  Things could go wrong I suppose, but for my list of finding what seems to be going wrong more often than the other, the other items is that.  So when you're feeling your cone, I guess some people are trying to strike.  Off after the Crown is filled, but that does not in either ASTM or AASHTO, so that should not be done when you're filling your cone, you.  Should just immediately apply your tamps.  The second nonconformity on the list regarding the cone, the slump test, this nonconformity is describing that some people out there are using the provisional cone test to perform their slump test on materials that easily slumps.  The provisional contest is used for only materials that are cohesive or don't easily slump.  So, if you have normal sand and that will slump readily and you should go ahead and use the.  First cone method.

00:19:37 BRIAN: Don't you run into?  Issues where people have trouble judging that.  SSD condition.

00:19:43 CHRISTINA: Yeah, we do.  And I'm surprised that this isn't on the list, but a lot of people will claim that the material is at SSD when it has either, you know not slump enough or is just a pile of dry sand on the on the counter.  So, I do see that a lot.  So, I'm surprised that it's not on this list.

00:20:01 BRIAN: One thing I wonder about with that is it is such a subjective determination of, you know, how moist is the SSD condition.  So, the people who are really experienced at the test, they often are able to determine it really easily, but it can be really challenging and I do.  I have to mention that sometimes technician nerves cause some issues.  I find that this one is the most difficult for an assessment for a technician because not only do they have to kind of.  You really have to baby this stuff.  You've got a pan with sand laying out and it has to get dry but not too dry, and sometimes there's a fan on it.  It kind of mess around with it and you know, play around with it, trying to get it to be the right consistency and have it be homogeneous.  But you're also at the same time.  Asking the person to do other things.  During the assessment, often to get everything done in time.  So, I think that's a really challenging activity for people.

00:21:02 BRIAN: So, I wonder if the absence from this list is mainly because assessors really have a hard time wanting to write that up, even if somebody kind of struggles with it because they kind of understand what that technician's going through and.  Maybe give some leeway, as long as they understand what that SSD condition is supposed to look like.  In the end.  Christina, what do you do?  You agree with that?  Or do you have?  Any other thoughts about that?

00:21:26 CHRISTINA: Yeah, I absolutely.  Agree with that.  A lot of the time in.  Let it go, and then we'll come.  Back and you know, oh, we just missed it.  But we were doing something else.  So we'll talk about it and the technician will describe well it.  I would have come back before and it would.  Have looked like this.  And this is what we would have done and there's no way.  I could be like, Oh no, sorry.  You know, but definitely nerves come into play in timing just because in an assessment we are on a, a a schedule and we have to follow it.  So we don't necessarily always have time to.  To really saturate our sample and start over.

00:22:03 BRIAN: What do you think about that, Ester?

00:22:05 ESTER: I agree, I've seen this happen a couple times.  I think sometimes technicians get state methods mixed up with their ASTM or AASHTO methods and it's good to have a little leniency, something that's often forgotten though too is that.  If it does go past SSD because in reality when you're in the lab, sometimes it can take half a day for these things to dry the SSD so you don't have time to just focus on that for, you know, 4 hours.  So you're going back and forth, but.  You do have an allowance to add water and cover it for 30 minutes and then try again.  You can do that one time with both test methods that something to keep in mind, and if you do get it past SSD.  I agree with Christina and Brian on these, that it is a difficult.  Thing to get to SSD and not get past it or be just under it, or making sure that you have it correctly.

00:23:07 ESTER: Another thing I've seen, you can test your sample to see how close it is to SD by tapping the countertop, but I have seen people tap the countertop, it's slumps and they say oh, it's ready.  That is not allowed.

x So keep that in mind when you're testing for your SSD.  If you tap it and it slumps, that does not mean that it's ready.  That means it's close to being ready, and you might need to just.  Give it another test.

00:23:31 BRIAN: So, what kind of corrective actions would you expect to see for something related to this?  Do you need to do you need to see a video of them demonstrating it properly, or is a written confirmation getting faster?

00:23:44 ESTER: I would love to see a video, but I think a written confirmation would be all that we would need in reality so.

00:23:51 BRIAN: Most people are confused about how far to to take it with the corrective actions.  And there are times where we've requested videos for demonstration, and particularly that comes up in the masonry concrete sections where they may have made mistakes or or just shown a complete lack of understanding of the of the test method requirements.  So they may have 8 procedural steps in a row on the same activity that should take about 30 seconds to complete.  So rather than saying, OK, they said that they know how to do this.  Now we would say, OK, well.  Seem like you're pretty far from knowing how to do that during the assessment.  So then we want to see a video for that, but that necessarily isn't going to happen every time they have a procedural non conformity.  But those are the five that we have on our list today for fine aggregate specific Gravity, AASHTO T 84 and ASTM C128. Kim as you listened to all these discussions, what came to mind for you?

00:25:00 KIM: Ester and Christina.  What did you expect to be on this top five list that wasn't?

00:25:06 CHRISTINA: Our times.  In an assessment I will see.  A lab that I signed up for both AASHTO and ATM, but they will only be following the AASHTO version, so they'll take.  A companion sample in the beginning.  Of 500 gram sample for their moisture content and so then at the end of the test they will remove the sample from the pycnometer and throw it in the oven.  That the moisture.  So I see that.  A lot, and then again that would only be an ASTM only finding. : I think that that's one.  I see very frequently not.  I'm kind of surprised it's not on here.

00:25:37 KIM: Ester, what about you?

00:25:39 ESTER: Those are some of the bigger takeaways that we already addressed.  If I had to say something, it would probably be reporting it to the nearest .01 rather than to the nearest .1 for the bulk specific gravity, and AASHTO requires it to be reported to the .001, so we are reporting would be something to look at when it comes to those test methods.

00:26:03 BRIAN: One other thing I was thinking about is we were talking about this test in particular.  Is that this is one that gets included in the suspensions.  Related to proficiency sample testing quite a bit.  So there are certain tests that show up a lot on the suspension list.  This is one of the main ones.  So Christina.  Why do you?  Think this one might be so common for repeat low ratings on proficiency sample tests.

00:26:32 CHRISTINA: I don't actually know, but if I had to, you know, go off my, my, my gut, I would say temperatures were adjusted or the sample was not agitated long enough to eliminate all of your bubbles.

00:26:44 ESTER: I agree with both of those and I think I would add that maybe the SSD is not where it needs to be because that is such a fine line between over and under.

00:26:56 BRIAN: Kim, anything?

00:26:58 KIM: No, I think you covered it. I kind of followed along and I.  Think I don't have any other.  Ohh Ester has something though.

00:27:06 ESTER: I think there's one more thing that we could bring up and that would be that little caveat that AASHTO has.  where, you can have the 500 gram sample for AASHTO you can. [CHRISTINA: I just said that.]  Oh, did you?

00:27:22 CHRISTINA: Like a second ago.

00:27:23 ESTER: Ohh OK sorry.

00:27:26 BRIAN: Oh, the split sample where you've got the dry.

00:27:29 KIM: Companion sample is, I think what Christina called it.

00:27:32 ESTER: OK, I missed that, sorry.

00:27:34 BRIAN: Look at You Kim, you're ready to to run that test.

00:27:36 KIM: Ohh please no.  That would be.

00:27:39 ESTER: I missed that you said that.  Sorry, but yeah, I.  Think that's one that I know?  I think I'm.

00:27:44 CHRISTINA: I'm surprised that wasn't on there.  I see.  That one a lot.

00:27:47 ESTER: So if I could change my answer from whatever I said before about.  What surprised me?  About not being on there, I would say that the companion sample.  That is allowed this AASHTO.  It has to be 500 grams within .2 grams. Of your 500 gram sample. So the allowance is 500 ± 10.  So if you have 499.9, it has to be 499.7 or 500.1 so.  That is the caveat with that companion sample.

00:28:23 CHRISTINA: Ever seen that written up?  Like has?  Have you ever seen someone take their companion samples out of that?

00:28:29 ESTER: I have.  I don't know that it's a common finding, but I was surprised that it wouldn’t be on there. 

00:28:33 CHRISTINA: Actually like, never really fussed too.  Much about the order.  Of about kind of lost our paying attention.

00:28:40 ESTER: I've also seen where they'll like do that for when they're running, ASTM, but it's like an AASHTO, only caveat.  So I think that's where it gets written up more than. [CHRISTINA: For sure.]  That they're out of that point to.

00:28:56 CHRISTINA: Other than that, like.  The demonstrations that this always go really.  Smoothly I don't.  I don't often write up a lot of findings, so I am kind of.  Surprised that it is one.  Of the more frequently suspended test methods for PSP.  Because you know, those restrictions are always really smooth.

00:29:10 KIM: Do either of you have any advice for laboratories that might be consistently struggling with?  Aspects of this are these standards.

00:29:19 ESTER: Kind of advise them to.  Check their equipment that they're using.  Make sure that you're getting your sample accurately.  That sample size that you're using and going over the steps, make sure you're doing that according to the most current standard.  Just double check those types of things.  A lot of the time it's either the equipment.  So you're missing a step in your.

00:29:43 CHRISTINA: Again I would echo or Ester has currently said, read your standards, make sure they're updated, and then I would also say check your temperatures.  And standardize your flask.  Regularly, if you're not doing that.

00:29:55 BRIAN: Yeah, I agree with that that it seems like that happens a lot as people forget any of these specific gravity tests are just relative termination, so.  Determining that mass of your flask, the flask filled with water.

00:30:07 BRIAN: Doing those more frequently is better because if your scale is drifting, so are your measurements and you really want those to be determined about the same time that you're running your test so that you get the right, you're doing an apples-to-apples comparison.  So that's a good tip there.  And I would say as everything.  Practice, practice, practice.  If you want to get good at it, especially when we're talking about the subjective determination of SSD condition.  Bring people together in your laboratory. Talk about it. Practice. Make sure everybody's on the same page. Make sure you're on the same page with whoever you're trying to compare with.  So that you guys can get the most repeatable measurements possible.

00:30:46 ESTER: Another tip I'd like to add is make sure when you are running your proficiency samples there are directions giving with those, follow those directions.  Don't just open the box and start running your sample.  Read the directions thoroughly and make sure if you're running ASTM or you're running ash toe, you're doing it according to that standard.  The test method don't overlap the test methods.

00:31:10 BRIAN: It's a great tip.  I wish I had that yesterday when I made the cake.  So thank you, Ester.

00:31:14 ESTER: Thanks Brian.

00:31:15 BRIAN: Thank you, Christina, for being our guest on the top five episode.

00:31:20 CHRISTINA: Thanks, Brian. Thank you, Kim.

00:31:22 BRIAN: And Kim, as always, thank you very much.

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