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In our podcast, we dive deep into metrology, calibration, and proficiency testing bringing you real stories, expert insights, and candid conversations from our 85+ years of combined experience. This isn’t just another technical podcast; we’re here to challenge the status quo, discuss industry changes, and tackle big questions like whether calibration labs are failing to train the next generation or if automation has gone too far. Expect lively discussions, industry leaders as guests, and a little fun along the way. As Howard puts it, “Proficiency testing is checking that transition from theory to application. But what happens when techs are just pushing buttons?” And Chuck adds, “We’re not teaching technicians how to measure anymore—we’re teaching them how to press ‘go.’” Whether we’re reflecting on our journeys—like Howard’s path from Air Force electronics to writing calibration procedures for the NFL—or debating metrology’s future, we promise to keep it engaging, informative, and unfiltered.
Chuck (00:19):
Welcome to ChatNAPT with AI chatterbox, Chuck and Howie. Another episode for all Things Metrology. I'd like to introduce my co-host for the podcast. Howard, how are you today?
Howard (Howie) (00:33):
Hey, fantastic, Chuck. How you doing today?
Chuck (00:35):
I'm okay. It's a beautiful day again here in Arkansas, ready to have another chat with you and share all things with ology. I got a lot on my mind. You know, I started writing down things that I've noticed with the people and believe it or not, it's only been a short time, but I've already got 20 things on the list. Well,
Howard (Howie) (00:52):
Look, remember we wanted this to be lively and entertaining. We don't want it to become drudgery where we lose our audience.
Chuck (00:59):
Well, I think the audience would start laughing as much as some of the things that we've seen, because it kind of goes towards the book I written. A lot of the thing is just a continuation of my book that I wrote.
Howard (Howie) (01:10):
I don't know if it's the older you get, maybe I'm showing our age that you grow less patient, especially when people do stupid things that are preventable. Let's just say those types of things. If it's one thing to make a mistake, right, everybody makes mistakes, including me, but for people to do things that are selfish and put others in danger, that's not good.
Chuck (01:35):
That's
Howard (Howie) (01:36):
Not tolerable.
Chuck (01:37):
Our guest today is no stranger to the podcast community. Our guest today is gonna be Dilip Shaw, you know, DI's been around a long time. He's got 45 years of experience in metrology electronics and instrumentation. He's the principal for his own company, equals MC Cube Solutions. It's a consulting company doing training, consulting, auditing solutions for 17 0 2 5 ing uncertainty computer analysis. Mm-hmm . You know, DILP has been around forever, right? I mean he's, you know, done the co-author for the Metrology Handbook. He's been around a SQ forever as well. He's written a number of things. He was huge with that project, with that CCT book. You were part of that project. He was huge with that. He's been very active on N-C-S-L-I. He was very active with A two LA for a long time. He was on the board of directors
Howard (Howie) (02:26):
For that. You'll see Dilla presenting and or providing training seminars at the conferences almost every time
Chuck (02:33):
And every conference. I mean, it doesn't matter if it's, you know, in N-C-S-L-I Embassy, you know, he's a mainstay. He tells me he's retired, but he's like me. We, that old thing from the Godfather three, how do I get out the more they pull me back in? The other thing would, he's got just about every award that's out there as well.
Howard (Howie) (02:49):
Oh yeah. I thought maybe we talked about to him a little bit about those and well deserved. Right. The guy's been around, not just because he is been around forever, but he's been so active.
Chuck (02:59):
I see you're wearing your Kansas City shirt today.
Howard (Howie) (03:03):
Yeah. I'm feeling a little nostalgic. Yeah. Even though we didn't win the Super Bowl this year, we went further than I thought we might. Right. And made it to the playoffs, made it to the Super Bowl. The reason I'm a chief Span is a happy wife, happy life. My wife's from the area. I was never in the football prior to meeting her, even though I was from Chicago, I was really never a bearish fan. I was more of a Covey's fan for baseball and her family pulled me in. Hello Della, welcome to the show.
Dilip Shah (03:28):
Thank you. Thanks for having me.
Howard (Howie) (03:30):
Yeah, we were talking about, you know, your a long illustrious history of contributions to the metrology industry. One of the things we really didn't get into detail is all awards that you've received, which are wonderful. Right. The 2023 William Wild Hack Award from NCSL, um, 2011 Education and Training Award from NCSL as well. 2010 Andrew j Winnington Award from MSC. There's a litany of others that is quite a testament to what we already know just from our experience in being involved with you and observing you over the years. So thank you for everything you do to support the metrology community and help new people learn as well.
Dilip Shah (04:10):
It's always, you know, something fun that you don't think about and that's how it's been down this journey. And so it's always a pleasure to, um, help the community and that's how what I've believed in, you know, you help the community, the community takes care of you.
Howard (Howie) (04:30):
Yeah. And you've done a great job of, you know, putting it into layman's terms for the beginners to be able to understand it and absorb it and retain it. That's really important.
Dilip Shah (04:41):
Yeah. And, and that's one of the important things people don't realize because everybody learns. Everybody has like a different level of learning, but I always learned if things were made simple for me
Howard (Howie) (04:54):
Mm-hmm .
Dilip Shah (04:55):
So I try to do that and what happens is once you get at a certain level, you forget about it. That even I have to be very, very careful about, um, making assumptions sometimes. And then I always get humbled because somebody asked me a question and I say, oh darn, I forgot. I should have explained this a lot simpler, so
Howard (Howie) (05:18):
Mm-hmm .
Dilip Shah (05:18):
Yeah. But it's a tough thing to do.
Howard (Howie) (05:21):
So I was thinking back when we first met, and I believe it was in Toledo. Mm-hmm . And you're, you're from Toledo, correct?
Dilip Shah (05:29):
No, I am in Medina, Ohio, which is about 40 miles southwest of Cleveland. 40 miles.
Howard (Howie) (05:36):
Okay.
Dilip Shah (05:37):
And Cleveland, I lived in this one place for this year. It'll be 45 years. Same place. Wow.
Howard (Howie) (05:43):
Okay.
Dilip Shah (05:44):
I have a, this five acre property.
Howard (Howie) (05:47):
Beautiful. Ohio's a beautiful state if you haven't driven through it. Um, I went and visited a customer out there years ago, probably 20 years ago. And it was heavy thunderstorm, right?
Chuck (05:58):
Mm.
Howard (Howie) (05:59):
And you know, I lived in Orlando, Florida for 12 years and you talk about lightning storms, there's some magnificent lightning storms there. Yeah. The whole southeast is full of that type of thing. But this was a pretty healthy thunderstorm with lots of lightning and just driving through the farm, the different farms out there and just seeing the beautiful crops. It was just a beautiful drive.
Dilip Shah (06:21):
Yeah. It, it's like people say, why don't you move? And I said, I'm very happy where I am. Yeah. I enjoy, I have all the, the major sports teams, the arts and everything within 40 mile radius of May and anything you wanna do, you know, it's there. So
Howard (Howie) (06:39):
Yeah. So, so we met, I recall at the conference, it wasn't a conference, it was a training seminar that I believe Phil Stein put on one of his last
Dilip Shah (06:49):
Ones. Yes. Yeah. That was in,
Howard (Howie) (06:51):
Was that on certainty training or was that something else? What was the
Dilip Shah (06:54):
? Yeah, so it was um, a SQ conference. And that was back in 1999.
Howard (Howie) (07:01):
Yes it was.
Dilip Shah (07:02):
And Phil Stein was doing a measurement uncertainty class and there was other things he was doing and I also met Chris Gretchen and the same time
Howard (Howie) (07:13):
Bad.
Dilip Shah (07:13):
Okay. Yeah.
Howard (Howie) (07:14):
That might've been the first time I met Chris. I don't recall. Yeah, we were trying to, Chuck and I were trying to recall when we met, first met Chris and that might've been the first one for me because prior to that I was in the lab, I was a technician, I really wasn't getting out much. And 99 was my first year of getting out to these conferences in Toronto in 99 or 2000. That was my 2000 was my first year in Toronto for NCSL.
Dilip Shah (07:38):
For NCSL. Yeah. That was the only conference that was really international that was outside the us. They went that we said the
Howard (Howie) (07:47):
I-N-T-S-L-I.
Dilip Shah (07:48):
Yeah,
Howard (Howie) (07:49):
Exactly.
Dilip Shah (07:49):
Yeah. And there's some important things about that 1999 conference in Toledo. I don't know if you remember, but at one of the evening meetings we sat together and Chris Stein and everybody and was put the out of a basic foundations for the Certified Calibration technician exam.
Chuck (08:12):
Oh yes.
Dilip Shah (08:13):
That was the sort of a like startup and get the ideas in process. And Phil Stein was the basic, the driver behind it. Yeah. .
Howard (Howie) (08:24):
That's awesome. Well, I was glad that I was at that event and I'm glad that I met you.
Dilip Shah (08:29):
Yeah.
Chuck (08:30):
Well, let's go back a just a little bit before we talk about your meeting. What brought you to Metrology Dilla? How did you get involved in metrology? What drew you into the metrology business?
Dilip Shah (08:42):
My career started in metrology when I was seven years old.
Howard (Howie) (08:48):
Wow.
Dilip Shah (08:48):
And so ,
Howard (Howie) (08:49):
You got me beat,
Dilip Shah (08:51):
You know, I am a November child and I'm like the oldest guy in the class. So I was starting first grade. I hadn't been to kindergarten or anything. I just started, you know, in first grade and you know, but your parents give you this brand new book bag and pencil box and everything. Well, in my pencil box I had two rollers and the first thing I did was I lined them up and I found out, you know, that I zeroed them up in the start, but at the six inch mark it wasn't perfectly lining up. And Oh, that's awesome. So basically I said, well, this should be the same. And I used to always follow my dad, you know, my dad was a all around guy. He would do carpentry, he would do whatever, you know, around the house and I'd see them measure with, you know, big rulers and so on. So I said that, which one is right. And he didn't have an answer for me, but he was very quick weighted and he says, son, that's why you're going to school. You go figure it out. He did. And basically I just was really just interested in measurements. Yeah.
(10:09)
I always wanted to achieve the perfect measurement. And so, you know, I seen my dad cut wood and you know, it'd line up the yardstick and the
Howard (Howie) (10:20):
Twice cut once. Right.
Dilip Shah (10:22):
Yeah. So I always had that. And then, you know, in the, that pencil box you had the protector and the angle squares and all those things. So I was used to, you know, mess with it, draw a triangle and measure the angle with a protector and see how well I can achieve the same thing and and numbers. I just love numbers. So, but, so this is a true story and
Howard (Howie) (10:51):
Well, you know, that's an astute observation for a 7-year-old.
Dilip Shah (10:54):
Yes. That's
Howard (Howie) (10:55):
To even take that step, to line them up to say, you know, Hey wait a minute, these things are off .
Dilip Shah (11:01):
Even now, like when I go, you know, to Staples or any, you know, store and there were bin of rollers and if there are wooden rollers, plastic rolls are pretty consistent in the metal ones, the wooden ones, because all those markings, the graduation are stamped in. There's always an error. And even now I say, ha, I found one like , it doesn't match.
Howard (Howie) (11:26):
So years ago we did some training, a couple of, one of my colleagues and I did training for our salespeople. Um, and he was looking for some examples just trying to pay attention everywhere. He wanted to see if there were real world examples of metrology that they could relate to. Right. Because salespeople are technically typically not technical. Yeah. And so he is just trying to relate it, which makes sense, right? He's in the grocery store, he sees an end cap that has hand soaps and there's like three different scents and of course different colors as well. And he is looking at those and the fill, the amount of volume in each one is clearly different. Like they're not even sitting next to each other. There's some on one shelf, some on another, and the third one on the other. And he is looking at those going, that's pretty far off. So then he picks one of each and he lines 'em up and then he goes and finds the worst ones. Right. Worst examples. Mm. and bought those and brought 'em in for the training class to say, look, these are all the same price, they're just different sense. They should have the same volume. There's a problem with their fill process. Right.
Dilip Shah (12:30):
Yeah.
Howard (Howie) (12:31):
And, and so that, that was a good way to segue into the whole measurement and control of the reason metrology exists.
Dilip Shah (12:38):
Yeah. And you know, um, one of the things like I always, I travel a lot so I always weigh my back.
Howard (Howie) (12:45):
Mm-hmm . Of
Dilip Shah (12:46):
Course now I've got, you know, the different status with airlines so I don't have to worry about that 'cause I can have bag up to 70 pounds. But back when I didn't have that status. And so I had a little balance that, you know, I had calibrated uhhuh and I'd weigh my bags and I went to an airline counter and I say, okay, this sweat bag is one and a half pounds over . And so I said, well, I waited at, you know, before I left and I, you know, I said, I'm in this business. And so I said, do you mind if we weigh on the other scale for the other counter scale? And the agent, she said, yeah. And so there it was one pound under . So, so then I said, okay,
Howard (Howie) (13:35):
And these are calibrated skills. No.
Dilip Shah (13:36):
Yeah. And because I said, you know, I'm in this business and I said, which one is right? And at the end of the day, she just let me check it in without paying the charge because I say, you know, if you charge anything but by weight, volume, length, it's legal metrology and you have to have this calibrated. And so there were people in the line behind me and they were like smiling and so yeah. Somebody won finally that that didn't have to pay the access baggage fees.
Chuck (14:10):
Right.
Dilip Shah (14:10):
But those are the kind of stories that, you know, you gotta chuckle out of.
Howard (Howie) (14:14):
Um, you mentioned, you mentioned legal metrology and for our audience who may not be aware, there are different types of metrology, right? Yes. Legal metrology that Dilip was talking about is, again, it's typically weighing scales. Now that's not all there is, right. It could be commodity mm-hmm . Exchange for volume of, you know, gasoline or fuel or any type of liquid where you're transferring commodity from one owner to another. Yeah. But typical things in everyday life that you're gonna see is when you go to the deli and you're buying some meat and they're weighing it on the scale, those scales have to be calibrated. Yeah. Same thing when you go to the post office to mail something and, and they have to weigh it out to see how much the fee is. Those have to be calibrated scales, truck scales on the highway, um mm-hmm . Cattle scales or any type of livestock scales to determine how much weight there is and you're selling the product by weight.
(15:05)
Those types of things are legal metrology. And the reason that's different than the other types of metrology, which are scientific and industrial metrology, is because legal metrology is not gonna go back and make a correction. If they find an error, they're not gonna go give you an extra slice of meat if it was off when it was calibrated six months later. Right. They're just gonna fix it and move forward. Yeah. Industrial metrology is more interested in, hey, there's something wrong with the instrument. It's outside of what we expected it to be. Whatever its parameters are allowed to be, we need to now go back and see how that impacted every measurement it was used for, because it could have a detrimental effect. And that gets more into legalities. So industrial metrology is gonna live backwards and try to set it correct going forward as well. Legal, legal metrology is only gonna correct it and go forward. They're not gonna go back and fix it. Same thing with gasoline pumps, you know, at your gas station mm-hmm . Um, and then scientific metrology is more involved with the definition and realization of different measurement units and the traceability chain. So just wanted to make that, it was a good point that you brought up about legal meteorologists. Wanted to clarify that for our audience who may or may not understand that.
Dilip Shah (16:23):
Yes. Excellent. And you know, the business we are in, which is that industrial metrology, uh, it's kinda interesting because, um, sometimes let's say if that balance that I was talking about was something that we were calibrating and it was off by the one and a half pounds I mentioned and if he adjusted it, um, so one of the things that I worry about is, um, how good is that measurement? And that gets into the traceability and accuracy because one of the dangers in the business we are in is sometimes we over adjust and if we over adjust, it has got, you know, if I just adjust that based on that one measurement and didn't look at the whole range and all, all like that, right? It has other consequences. And uh, for those of you that are interested, um, you could Google, Dr. Deming was a quality guru and Dr. Deming talks about this dangers of our adjustment and it's called the Deming funnel experiment. So that's something really neat to see. Like what can or adjustment do for you? A lot of labs will overreact and they'll have a knee jerk reaction without studying the variation in their measurement. So that's the other thing I just wanna mention that in our business that we have to be careful that wouldn't,
Chuck (18:06):
Wouldn't you say almost every Cal lab does that a lot? Mostly they just a nominal.
Dilip Shah (18:12):
Yeah, it is possible because now when a Cal lab has a customer's equipment, I mean that's the only chance they have. And now if I was a customer sending my equipment to a Cal lab, I would tell them like, tell me how far it's off by. But again, I am an educated consumer.
Howard (Howie) (18:34):
Mm-hmm .
Dilip Shah (18:35):
I know a lot about stuff, but most consumers of calibration services will basically say Yeah, just to nominal. And if you do that, then that demo demings, you know, funnel experiment scenario happens. So the issues related to over adjustment because the next time you measure it, it may not be off by one and a half pounds, it may be off by half because there's variation in everything we do. And that's part of that random variation that we have to look about. So, um, it's a very fascinating thing that he demonstrated and he did that back in the 1980s and he was demonstrating that to the, back then it was the big four automotive, uh, CEOs and they were talking about, you know, the problems they had and they say they get everything down to the exact values and their drawings and they were still having quality issues. And he says, yeah, that's the problem because you don't know the variation associated with your process and you're over adjusting without studying the variation associated with your measurement process.
Howard (Howie) (19:53):
Yeah. In my undergraduate and graduate programs, we studied Deming insured and Deming was really focused on process capability. Yeah. And um, you know, not just the shift in the process, but the variations in the process as well. Yeah. Yeah.
Chuck (20:11):
Interesting. Okay. What are some of the misconceptions then that these labs can adjust without really making mistakes? You know, do they have to do, apply this principle every single time? Because when most Cal Labs, they get something, they don't have time mm-hmm . To do the research and do the variation analysis before they wanna adjust it. Would you recommend that they don't adjust it?
Dilip Shah (20:37):
Well, um, one of the things that should be part of the discussion between the supplier, the calibration labs and the consumer is instead of just calibrating it or adjusting it to the nominal, um, you know, everything that calibrate is to a certain specification. So, um, you should like decide like if it's within let's say 10, 15, 20% of the specifications, then leave it as it is. And if it's beyond 70%, 80%, then you digest. So you would've some kinda decision rules. Now when I said decision rules, obviously we have other decision rules that, um, 2017 brought out, but I'm not talking about that decision rules. Right. So I wanna make sure, but but that should be the thing because we have this sort of thing like we wanna get it perfect, but it's really perfect this one time. Right. You made that adjustment later on your one measurement and I call it the single measurement bliss.
Chuck (21:52):
Yeah.
Dilip Shah (21:53):
And bliss is ignorance in disguise and because next time you measure the same artifact and you adjusted it, now you know it's off by on the other side, you know, it's high by one pound and so on. That's a tough thing that, and it's an education process not between the labs and the consumers too. Yeah.
Howard (Howie) (22:19):
I mean there's variability in the measurement process and we're talking about leading into measurement uncertainty.
Dilip Shah (22:24):
Yeah.
Howard (Howie) (22:27):
Good. Um, so we do have some customers at Transcat who require nominalization every time. Mm-hmm . And they may have their reasons for that. They also may not understand this whole concept of measurement bliss. Right? Yeah. And measurement uncertainty. I wouldn't say there's very many, but there are some. But to your point then, how do you determine what that decision rule should be or when to make the adjustment? Is there a hard and fast? Is there something standardized in the industry or is it case by case?
Dilip Shah (22:58):
Uh, it's really case by case. And my argument is the lab should not make that rule for the end user, the customer. And that's a difficult thing because, um, what happens is the customer is looking at the calibration lab and they're the experts most of the time. I mean, probably 90% of the base wants a calibrated equipment, which is perfect. Meaning, you know, it has set at the domino value. The other consumers that are probably calibration labs that are sending their equipment to get that traceability, those are the ones that are gonna tell you I want to not to adjust it or adjust it
Chuck (23:51):
Mm-hmm .
Dilip Shah (23:51):
Uh, when it's, you know, 15, 20% Right. Outside calibration and so on. And then obviously it's just not the data point. And then you got the measurement uncertainty associated with that and so on. So, but there's no hard and fast rule. It's really the end user. So calibration labs basically have a huge challenge to educate the customer and it's always gonna be, uh, uphill battle. Um, because end of the day the, once the equipment calibrated as as soon as possible and mm-hmm . Hopefully, you know, there are no issues with their equipment
Howard (Howie) (24:33):
And some customers are curious about it. There are customers who don't want to have it explained to them. Right.
Dilip Shah (24:40):
Yeah.
Howard (Howie) (24:40):
But they don't know. Right. And so that's the challenge.
Chuck (24:43):
Mm-hmm . I would say most consumers don't wanna explain to 'em. I vaguely most customers just want it calibrated.
Howard (Howie) (24:50):
Yeah. Well this goes back to an old paper, right? Written by Shell Stein called Buyer Beware. Mm-hmm . And there's been versions of that that have been updated, right? Different, same concept but different papers. But it's the whole concept of, you know, trying to relate calibration services, uh, to what you, what you experience in everyday life. And a typical example would be you take your car in for service, you don't really know the details of your, how your vehicle operates and what can go wrong and what can't. Or if they're ripping you off trying to make money or if they're actually telling you the truth. And so isn't it in your best interest to know more? You don't have to be an expert, but you gotta know more so you can judge whether or not what they're telling you is right or whether you should push back against it.
(25:37)
Same thing with healthcare. You know, being your own advocate is the best, safest way to go because the doctor's not always right. I mean, you've got more education than you do in that specific field, but it's to your best interest to have some ability to weigh it out. Right. Same thing with health services. You should be able to understand basic concepts. And I've had some consulting I've done, and I'm sure you've had the same situation where you'll take a look at a caler, you'll look at how the instrument was calibrated, you'll point out some obvious errors, not necessarily trying to, you know, be biased, but just to say, here's some things you could verify yourself. And I'll give you one example of that. Had a customer who had a temperature instrument calibrated, had two channels at one and two, four different thermocouples, jk, t and E on both channel.
(26:31)
If you look at the calibration, sir, and only channel one and JK was scouted and that's it. So my question to the client was, Hey, where are you using this thing thing? How are you using it? Let's go back and look at that application. And what they found out is they're using both channels and JK and t thermocouples on both. So my next step was to say, now you should see from the cert that this other channel's not calibrated at all, and your T cut thermocouple on channel one's not calibrated, but you're relying on those measurements for your product for pass fail
Chuck (27:05):
Mm-hmm .
Howard (Howie) (27:06):
And you have no traceability whatsoever. Nothing is checking that at all. Right. And we look back in the cow history and it had gone on for years. That's the buyer beware. I'm talking about. You don't have to be the expert, just take a look at how are you using it and is it, is it covering and do you have any questions that pop up? And if you do, then come to your account provider and ask some questions.
Dilip Shah (27:26):
Yeah. And, and you know, this is where the end user ultimately is responsible for their equipment. And, and what I tell the end user is if it's critical to you, then you should do some intermediate checks in between your calibration intervals.
Howard (Howie) (27:47):
Right.
Dilip Shah (27:47):
And because there's nothing like sending an equipment out for calibration, let's say if it's a one year interval, and then find out that it's out of tolerance. Right. Now you gotta do all that investigation.
Howard (Howie) (28:03):
Yep. You gotta go back and look and that's that industrial metrology application. You gotta go back and see if it impacted any decisions you made on products passing or failing.
Dilip Shah (28:10):
Yeah.
Howard (Howie) (28:11):
Um, and we've had, I've seen some examples where there's five 10 year calibration intervals on equipment. Now maybe it's lower risk for how they're using it and whether it really impacts product or not. But have they considered that? A lot of times you'll hear them say, I don't know who made that decision. Those people are long gone. Yeah. And yet they're living with that risk.
Dilip Shah (28:34):
So yeah,
Howard (Howie) (28:35):
Mitigating risk is also not just about the measurement, but it's also about the cal interval and reviewing certs and understanding how these things apply.
Dilip Shah (28:45):
Yeah. And sometimes, you know, we have a reliance on manufacturers suggested calibration interval.
Howard (Howie):
Yeah.
Dilip Shah:
And I say, yeah, that is fine, but you are not exactly using it. The equipment, the way the manufacturer anticipates that you're going to use, everybody's gonna use it. You know, somebody's gonna use, you know, digital multimeter by a still blast furnace, which has got 140, 150 degrees, you know, fahrenheit temperatures versus somebody's gonna, you know, use it in a pristine pharmaceutical manufacturing equipment. And so, um, if, if you rely just on the manufacturer's recommended calibration interval, you are setting yourself up for some kind of risk that's gonna come Yeah. And hit you. So, so
Howard (Howie):
Those interim checks you're talking about, sometimes they're called cross checks, sometimes they're, I just call 'em sanity checks or, you know Yeah. Risk, risk mitigation checks. And it doesn't have to be a traceable standard that a Cal lab would use. Just my recommendation on those interim checks is when you get the thing back through Cal, you get an instrument back from calibration, whatever you're gonna use for your crosscheck, make a measurement right. Then
Dilip Shah:
Yeah.
Howard (Howie):
Then, you know, from my crosscheck, here's what it was reading today. And let's say it's a one year accountable at six months, I'm gonna check it again. And if it changed appreciably and how much is appreciably, well, we talk about it in a different conversation, but if it changed enough for you to be concerned, you might wanna have it calibrated before you let it go another six months and then you have a recall.
Dilip Shah:
Yeah. And um, there was one time I was working with a lab that were talking about intermediate checks and they were, um, they were doing pipette calibrations and so balance very important, uh, in there, but they say, what should we use? What kinda standard do we need for these balances? You know, once they calibrated and I kind of stayed in a jovial mode and I said, well, you go out in the yard and you pick a stone, a rock and use that. And as long as the rock is stable and it doesn't crumble, it's consistent. Right? Yeah. Don't have to have a precision weight or anything like that. And that's what I was trying to say, because they thought, oh, we gotta buy a, you know, class zero zero oh yeah. Weight set and all those kind of things I said matter, it's just a sanity check. You want us make sure the rock weighs the same all the time. Yeah. And, and first they were like, you know, baffled by that. And then once they realized like, okay, it doesn't have to be, you know, ultra class weight or anything like that, I say, these are the things you have in the lab and you're doing crosscheck. So I like the sanity check. Yeah.
Howard (Howie):
It is a sanity check. So I'll go back to your example. At seven years old, you got two rulers. You line them up at the bottom end and they're off a little bit, so you know there's something wrong and you don't know which one's correct. Yeah. For absolute measurement, but that becomes a good crosscheck, right? Yep. For when you do have them calibrated and then it's, they're both intolerance, but they're just off by their part of a minor division that's less than tolerant. That could be good, a good crosscheck to say, okay, it's still at that amount of difference every time I check it or No, it's shifted again because you wore the end of it down or something. And so that's what you're talking about with a crosscheck doesn't have to be the calibration standard. It could just be anything that says it hasn't changed.
Dilip Shah:
Yeah. And you know, I once like going through the grades and so on, once it got started, and I was very fortunate to have really, really good teachers all through high school and we started doing calculus back in eighth and ninth grade and derivatives and integration and so on. And I posed that question about the rulers to my math teacher.
Howard (Howie):
Yeah.
Dilip Shah:
He was a really good math teacher, but he wasn't a meteorologist , so he wasn't a practitioner. So he kind of gives me a quizzing look and I kind of explained that to him and I said, look, these are rollers. And back then you all you had was wooden rollers, so, uh mm-hmm . I said, you could take any two and put together and though you'll have a difference. Uh, didn't happen
Howard (Howie):
To have an Egyptian cubit sitting by that you could measure.
Dilip Shah:
No. And of course that has its own set of problems, right? Because
Howard (Howie):
Yes,
Dilip Shah:
It was based on the living pharaoh's middle finger and the tip of the elbow, but they were able to still build pyramids and you know, with the accuracy we can't achieve in certain things why
Howard (Howie):
It's called a ruler.
Chuck:
Yeah. . Yeah. Let me change gears a little bit here. Let me, um, okay. You know, de you're an expert at statistics and you've got quite a bit of familiarity with PTs. We, you know, back in the day you ran a PT organization, and I want to get your opinion on doing PT statistics. Do you think that 13 528 is appropriate, or do you think there should be other methods that providers should be doing analysis by?
Dilip Shah:
Well, the 13 5 28 and, uh, what Chuck is talking about is the ISO 13 5 28 standard, and it gives you different statistical methods for evaluating your proficiency test results. And it's got a lot of different methods in there. So there's a lot in there, but it doesn't constrain you to just use those. There's probably a lot of, a lot more other statistical methods in there. So, um, and one of the things I deal with is I deal with both the testing and calibration labs. Okay. Now, in the calibration labs from the PT perspective, most of the time you use the e bend number and that's like our, like the judge to say whether we pass the PT or not. But when you fail that then you know, you have to do a corrective action and then you say, okay, let me look at it and analyze it statistically and what is appropriate or not. Um, but the 13 5 28 standard has a lot of methods in there, and it is a good standard in that respect. But there are times where you may wanna look at other things. One of the things I look at is I look at analysis of variance.
Chuck):
Mm-hmm .
Dilip Shah:
That is a nice and quick and easy way to do that. And, um, Excel is already, you know, has a built in function to do that. Uh, but there are other statistical methods that you could look at too.
Chuck:
Yeah.
Well I, you know, I know it, we, we pretty much don't depend on the, you know, robust analysis or weighted mean is our, our preferred methods that we do. Probably 90% is our, are the means that we methods that we choose to do our analysis on. Yeah. But we do mostly all, you know, calibration is what we, our, our labs are. But yeah, testing, I can certainly see where other methods, but you know, I'm just curious, you being an expert, I could, you know, pick your brain for a minute or two if there were other methods that you thought would better give us, that we should think about. And we are trying to make sure that we establish a proper reference value because, you know, that's the most important thing you can do. If you're not a hundred percent comfortable with that established reference value and the associated uncertainty of that value, then you're the, the entire test is meaningless. And that's gotta be accurate as can be.
Dilip Shah:
Yeah. So, um, so kinda maybe, um, let me just clarify. This is from the PT providers perspective, to make sure the reference value you establish for your PT artifact, you need to have a lot of confidence in it. And so establishing that value and then obviously establishing specifications for that. Now, those of you that may not be familiar, NIST as a semi semitech statistics book, it's available on NIST website. And one of the things they do a very good job of establishing tolerances for the artifact. Okay. So they kind of go through the method there and it looks at the kai squared analysis. So, but that helps you establish the specifications associated with your artifact. You still have to do the establishing the mean and establishing the mean. Obviously the 13 five to eight kind of talks about different way of establishing the main and the four or five methods are also in the 17 0 4 3, uh, you know, and one of the methods is how do you establish the main, and obviously uncertainty is the other part that, you know, uh, right. You would've to do a robust analysis of uncertainty associated with that artifact. Um,
Chuck:
Right. Yeah.
Dilip Shah:
Fred, I,
Chuck:
Let's need you some, let's gimme some fun questions, Howard. Yeah, yeah,
Howard (Howie):
Yeah. Let, lemme kick it off with this. Um, you had been a mentor for many, you've been an inspiration to many of us over the years. And I'm curious, who was your mentor when you were early on in your career? Who was your inspiration?
Dilip Shah:
Okay. And, uh, or multiple people you mentioned Phil Stein, obviously Phil Stein was one of my mentors to, and those of you, Phil Stein unfortunately passed away at an early age of 62. Yeah. Back in 2004. I was very unexpected in there. So, but Phil Stein was one of the mantras, but as I mentioned earlier, I was very fortunate right from grade one through grade 12 to have some excellent teachers. You know, like I said, I was doing calculus integration back in eighth and ninth grade and science and everything. And then I was also fortunate that our high school had the best physics and chemistry labs, and I used to volunteer as a assistant to set up all the chemistry physics labs. And so that was good. So
Howard (Howie):
Yeah,
Dilip Shah:
I would say most of my high school teachers was my mentors. One of my high school teachers was my mentor. He, he is alive, he lives in the United Kingdom, and so I have to give him credit for that. One of the chemistry teachers who was from Canada. And, but those were the guys because the foundation is very important. Any That's
Howard (Howie):
What I was gonna say, you know, everything you're talking about there
Dilip Shah:
Yeah.
Howard (Howie):
Gives you that really solid foundation that everything else you do is built upon.
Dilip Shah:
Yeah.
Howard (Howie):
If you have very weak having, having great detail there and, and that knowledge base is key to success.
Dilip Shah:
Yeah. Yeah. And it's kinda interesting because, um, I know in our physics lab in high school we had the cesium, you know, ent, it was, you know, lead en closure and so on. Of course, back then we weren't very, you know, safe about dangers of radioactivity and so on.
Howard (Howie):
Right.
Dilip Shah:
But that was a level, and it was kind of interesting. Both my sons, you know, were born here in the States and I used to like go to their high school to help out. But when I look at their high school labs and the ones I was in, there's a day and night difference. Difference. Yeah. I was so fortunate that I had those kinda, you know, labs with all that kind of equipment. And, and some of them, I mean, was primitive when we look at it now where we had the all like the wi on bridges with sliders and things. Um, and, and that really like made you more meticulous because you had to just get it right. You, you develop that art and technique to balance the bridge and when you do chemistry titration or like that, you just had to get it right or you had to start over again.
Howard (Howie):
Right.
Dilip Shah:
But yeah, so the mantras, but more recently Phil Stein, so those of you that may not know the, the, the people who listen to the podcast and Howard mentioned about some of the articles Phil Stein has written, Phil Stein started this column called Measure for Measure. It was in the A SQ American Society for Quality. If you're a member of American Society for Quality, they have a monthly quality progress magazine. And he started that column back in 1999. We were talking about 1999.
Chuck:
What a great year.
Dilip Shah:
A lot of things. And, and when he passed away, I was pretty active with the measurement quality division. I was in fact the chair. And back then he only wrote that. And, uh, uh, but those are available, if you remember all the ones that, you know, Phil Stein wrote and several of us wrote. And unfortunately, you know, I start to revive it recently, but a SQ is going the other way, but it should be really nice if, you know, somebody starts that kinda thing that would be regular.
Howard (Howie):
Well, the thing, one of the things that he wrote about are, are timeless. Right. There's still good concepts to learn from.
Dilip Shah:
Yeah. One of the examples is like, you know, we were talking about ruler, but the question that comes up is the resolution, especially with analog instrumentation. And so between the two divisions, how far can you resolve? Right?
Howard (Howie):
Yeah.
Dilip Shah:
And we say, well, all the best you could resolve is half whatever the, the units are, you know, and here an article and it says, well, you could resolve within 10 divisions
Chuck:
Mm-hmm
Dilip Shah:
. The invisible divisions as long as you do this, this, this, and this. And, and he based it because it's based on what NIST had done. And he, he cites the reference to the NIST scientist who did that, because back then that's all he had to deal with. And that's how we got the resolution.
Howard (Howie):
Yeah. That's, that's quite a feat to go 10 divisions between
Dilip Shah:
Yeah.
Howard (Howie):
Two solid lines. Right. I actually wrote a, a shorter paper on that just for information purposes, but in that, in that article I write about the fact that if you have one solid line and one imaginary line, you could go in between what you imagine there, and that's about it. So pretty much four divisions. Yeah. And the, the difference being you could go to five divisions in my mind, and maybe I'm right or wrong, but in five, five divisions because the, um, the value that you end up with or that division might be an odd number that doesn't fit quite right. Right. So if you have 200 PSI, let's say on a pressure gauge between two solid lines, if you divide four times, you could end up with 50 PSI per or imaginary division between, if you divide five times, it'd be 40 psi. So there's that one, it would make sense to just divide four times, but you might end up with a, a really strange number that has a repeating decimal, and in that case, dividing by five might make more sense, but now you've gotta go in between the imaginary lines. Yeah. And that's about the furthest I would take it. I know that steroid has had some papers on how they divide by 10 for between minor divisions, but mainly relying on the standard to tell them where they're Right. Yeah. Because it has greater resolution. But if you're using the gates, you can't necessarily do that. You don't have a standard attached to it. So 10 divisions questionable to me, but I I, I'll have to pull up that paperwork.
Dilip Shah:
Yeah. And basically says about doing a repeatability reproducibility study between technicians. Okay.
Howard (Howie):
Yeah.
Dilip Shah:
And so if you add a new technician, then you gotta go through that to make sure all the technicians can consistently read the same number between the divisions.
Howard (Howie):
Yeah. We're getting a lot of requests for problems with torque wrenches, torque devices
Dilip Shah:
Ah, yeah.
Howard (Howie):
From multiple customers. And that goes down to how you use them. Right. And trying to train that. You can't see the, the value, you just feel the click on a wrench. Mm-hmm. But how you apply it and how consistent or inconsistent you are can make a huge difference.
Chuck:
Yep. Yeah. Well, gentlemen, I I, I really hate to be the bearer or bad news, but believe it or not, we've already been talking for 45 minutes.
Dilip Shah:
Easy. Yeah. Time flies when, you know,
Chuck:
I, I know I, we try to keep the, the podcast between 30 and 45 minutes because podcast listeners, that's what they tell us. They won't listen to it. So, so obviously, you know, Philip 45 minutes is not enough time to even begin to talk about everything that you can share with us. So you're just another, a guest that we're gonna have to have back more multiple times because
Dilip Shah:
It'll be my pleasure to be back and talk about different things. So
Chuck:
Yeah, we probably next time we should, we should make a, a topic, because today we kind of wanted to talk about you.
Howard (Howie):
Yes.
Chuck:
And we, we ended up talking about other things as well, but we didn't, we still didn't get a lot of questions answered that I wanted to ask that were relative to you, you know, like where you went to high school and things like that. So we definitely gotta, we gotta have you back to make sure that we finish that part first and then we can explore the other topics. Like I said, I had a whole list of questions that I wanted to ask and we didn't get to it, so just not enough time. So with that being said, any, any parting words that you have? D
Dilip Shah:
No. Um, thanks for having me. It was a pleasure to be in that podcast and I'll look forward to like talking about other specific topics and I hope to the listeners you find this useful and the other podcasts that are there. So one of the things is, you know, we are all graying and we're gonna fade into the sunset and I worry about how do we pass this knowledge. Yeah. And then, you know, unfortunate things like Phil Stein passing away just suddenly and, you know, all that knowledge is gone. Mm-hmm . And that's one of the things I always worry about. And in any profession really, we should be having some kind of depository knowledge base
Howard (Howie)):
Agree
Dilip Shah:
That gets passed on because then people take that and build upon it and make it better and better and better, so,
Chuck:
Right. I agree. I'm with you on that. Howard, any last thoughts?
Howard (Howie):
Not today, Chuck. I think I'm all talked out.
Chuck:
Yeah. Well, my, my last thoughts are as always, you know, it's my humble opinion that proficiency testing is the only way that you can absolutely prove that you're technically competent. So if you're not doing proficiency testing, you're not technically competent, at least you haven't proved it. So sign up for a proficiency test today. So with that being said, thank you to our sponsor, national Association for Proficiency Testing, and we look forward to seeing you on the next podcast.
Howard (Howie)
All right. Thank you. Thank you. Bye-bye. I easy you up.