Evanescent Measurement Policy

By The Metric Maven

Bulldog Edition

One day I was visiting a production plant which creates and molds materials for electronic components. I noted they were measuring the length of the component in barleycorn inches with a few zeros at the front of the decimal. The data was being entered by hand onto a paper table held with a clipboard. I indicated that it would be wiser to measure in millimeters so the data didn’t contain so many leading zeros and provide such an easy opportunity for error—and there would be less redundant digits to write down. They next measured the mass of the object in grams with a scale that went way way down into the microgram range. It also had a large number of leading zeros to the right of the decimal point.

After they had obtained the mass (in grams) and volume (using inches) they computed the density or mass/volume. I was told it was expressed in grams per cubic centimeter. I did have an attack of the vapors realizing they were using pigfish measurement, and then converting to metric, and worst of all used cubic centimeters. The metric system has a nice unit for volume called the liter. A cubic centimeter may be a volume dimensionally, but it is a milliliter which is an appropriate volume unit in my view, and identical to a cubic centimeter.  The cc is a part of the cgs system, and has long been abandoned.

Along the way I was shown the dielectric material in granular form before it undergoes processing for later fabrication into electronic parts. The materials chemist was pleased to tell me that they were all created to be about 100 microns in diameter. I cringed slightly, and then said “you mean micrometers?  Micron is a term from the 19th century and is not expressive.” Little was said after my comment and we moved on.

During a discussion about part fabrication difficulties, mils (thousandths of an inch) were bandied about constantly. I finally asked about the surface roughness of the material. I had determined it could contribute to the problems they were having. I was given a value in microinches. A metric prefix with Ye Olde English?—sigh. I could only reply with “I have no idea what size that is.”  I was then quoted a value in microns. Again with the microns? I wanted to do a face-palm, but refrained.

I have been on many tours of engineering and production facilities. It was only when I was at this particular establishment that I realized, I’ve never toured ANY company that has a measurement policy or measurement coordinator. It is not discussed, contemplated, seen as a concern—nada. When I bring up metric measurements, it is as if my statements and questions vanish into a black hole of indifference.

A week or so later another engineering client sent me a drawing which has a part made from a similar ceramic material. The dimensions on the drawing were all in inches, but in the notes, the metalization thickness on the part was called out in micrometers. The second note described the density of the part in grams per cubic centimeter (g/cc). I just stared at the drawing, and thought about my recent visit. Inches, micrometers, and the cgs unit g/cc all on the same drawing? Three different measurement types on one drawing. Why does this strike only me as bad engineering practice?

Density is mass per unit of volume. The density value on the drawing was 3.73 g/cc +/- 0.1%. In SI the milliliter (mL) would be an appropriate volume which would be 3.73 g/mL +/- 0.1%.  The cgs/SI/Ye Olde English mixing of units has become so accepted in the US that it goes without notice apparently. As I said, thus far I’ve never seen a company that has a “Measurement Coordinator.”  This would be a person who would help create a measurement policy and apply Naughtin’s Laws as well as the rule of thousands. That person would examine, simplify and coordinate measurements to maximize the understanding of data presentation and reduce possible mistakes—and implement the metric system. It never occurs to business management that measurement coordination could be a cost or efficiency issue.

I’ve always been tasked with design work, and never anything which would involve setting measurement policy. Pat Naughtin was the first to discuss the fact that NASA’s measurement policy is “change to metric, if you want to, use centimeters and/or millimeters, if you want to.” In other words NASA simply didn’t see measurement policy as a problem which is in need of any coordination or effort. This means they don’t see it as a problem at all, and so they do not have a measurement policy. Unfortunately the current former head of NIST also has a “do your own thing” measurement policy.

In the back of my mind I wondered what the reaction of one of my clients might be if I brought up the possibility of a measurement coordinator. I had concerns about it, and the next time I was on the phone with Sven, I asked him what he thought the reaction might be from management and a group of engineers.

Sven: “They would not see any need for it, and they would look at you as if you were wearing a gunny-sack with a belt and sandals, had a long beard, and were holding a sign which read REPENT!”

MM: “I was afraid you would say that.”

Every engineer I know believes they understand measurement units and measurement. There is no need for a policy, we “learned” it all in college. Some co-workers have indicated to me that metrology is what people do who really don’t have any engineering talent. You can imagine how my psyche greeted that notion. I’ve met way too many “engineers” who embrace measurement methods which are ad hoc and unsound. They chase down blind alleys of impromptu measurement and waste time. But as long as a product “gets out the door” and appears to work—there is no problem here—move along.

Isaac Asimov in an essay called Forget it! pointed out that often measurement units that should have been abandoned long ago, continue to be used. The units are also only imperfectly forgotten, which leads to an even more chaotic usage. The cgs system was abandoned many years ago, but the inertia of unrestricted usage propels them into the future.

I spoke with a medical researcher at a block party last summer, and mentioned metric. He proudly stated he uses metric in his work and cited the cubic centimeter. I pointed out that the cc was part of centimeter-gram-second system, and the cgs system is not compatible with SI. He should be using milliliters. He looked at me as if I was daft, and going out of my way trying to be annoying.

The technical drawings I received with cc’s on them, show an incomplete ability to forget cgs, as do the density measurements performed by another client. Recall they first started in inches with a long number of zeros past the decimal point, then converted the inches to cc’s, and then finally computed grams/cc for a density. The inch is Ye Olde English, the gram is SI, and the cc is cgs. Both the inch and cc should be forgotten and eschewed; but the 10th, 14th and 19th  centuries live on in the US, never forgotten or allowed to be. They are the products of the “unexamined engineering life.”

I wholeheartedly agree with Pat Naughtin’s call for measurement coordinators and measurement policies in industry. As he himself pointed out, often questions of measurement are considered so minor, that scales and other measurement instruments are chosen and ordered by secretaries or interns. To show they are giving the company the most value, they order dual or multiple scale measurement devices. This perpetuates the farrago of units in use.

NASA demonstrated itself to be immune to the notion of measurement coordination even after the Mars Climate Orbiter disaster. The much less well-known DART “mishap” even appears to have been obfuscated with a mantle of junk prose. It was more important for NASA to deny there is a need for measurement coordination, than to address the problem. I really have no idea what it might take for the technical community, educators and the public to realize that measurements are the real currency upon which our modern technical society operates, and there is a need to coordinate and simplify them. I can only hope for the US metric coma to finally recede, the country to wake up, and then finally address the problem.

13 thoughts on “Evanescent Measurement Policy

  1. “His name is Standard. Leland K. Standard. He uses some of my girls, yes.”

    —prostitute in the 1981 Robert DeNiro/Robert Duvall film “True Confessions”

    Why do people of knowledge “turn out” measurement units as if measurement is the 14-year-old Iris in “Taxi Driver? It seems there is a whoredom among measurers that they would contaminate a process with multiple unit systems that begs to be unified under one world measurement system. It is as if they lust at measuring things, but will not respect the process in the morning. They want to show erudition, but at the expense of standardization. The status quo is illustrated in U.S. labeling. My bottle of Pellegrino sparking water just HAS to be required to tell me the bottle’s volume in fluid ounces AND quarts/pints AND liters! Even though it is the realm of the consumer instead of the engineer, the water product still shows that measurement is a universal activity which, in this standards-loving society of ours, deserves the respect given to Caesar’s wife.

    • Paul,

      The status quo is demonstrated in law, not in the bottling plant. The FPLA and FDA rules supporting it REQUIRE the metric volume, the Customary volume in cascading largest whole units (qts, pts, leftover fl oz) The FDA also encourages total ounces because it knows consumers don’t understand the cascading largest units as required by law. Until USMA and other metric supporters convince Congress to amend the FPLA to metric-only (either permissive or Customary-is-forbidden) the madness will continue.

      TL,DR: It’s Congress’ fault.

      • The marketplace loves confusion because confusion makes it impossible to

  2. I’m puzzled; this has not been the same as my experience.. I talk with engineers and see factories in my work with automation. The vast majority WANT to be working in metric. They might not be up on the sins of centimeters, they might use microns because that is what it says on the container, but they realize these legacy units are antiquated, error producing and should go away. (I find the younger ones quite receptive to learning about units).

    The problem is that of positive feedback. To make changes means a one time expense and confusing your customers. I have ordered PCBs with a Gerber file in metric – sent off to a so-called metric country, only to have them call and ask for it in Inches. The reason is they don’t want both coming in the door – as having both creates confusion, wastage, and change creates confusion.

    I work with legacy units – i ship in LBs, I deal with English threads, I use standard garden hose connectors, but when and where I can, I use metric. I’m not alone, every year more people are working in metric. I see movement – yes slow, but real. (yet I constantly confuse people talking about the weather in centigrade. )

    Realize that measurement is only one place where such insanity rules. Take English spelling – it is absolutely insane. It should be reformed – it wastes countless hours in needless memorizations. (to contrast it – I started studying Spanish one year ago – and already I spell better in Spanish than English – our foreign host students, struggle with our spelling exceptions constantly.)

    So it isn’t just measurement – it is a class of problems where what is done continues to be done that way because historically it is how it was done. It is frustrating.

    The best place to work on moving in the correct direction would be a bill that any procurement by the government needs to be in metric. The problem is that the election process selects narcissistic egomaniacs rather than the best person for the job (as a group they demonstrate very poor math skills, poor critical thinking skills and a willingness to be bought) so I think you will see resistance from some that think the legacy units act as a form of protectionist trade restriction.

    Yes it is not a perfect world. Positive feedback has far worse effects than the slow pace of metrification – think of the superstitions that lead to wars, poor decision process. ( for some reason we don’t teach about cognitive biases until after grade school – tradition?).

    Yes, we should ridicule the use of these obsolete units, but we should also rejoice that there is movement – the glass is more than half full ( my approx 500ml glass has well over 300ml in it).

    PS – my spell checker doesn’t know how to spell ‘metrification’

    • Cubic centimeter; milliliter. To-may-to, to-mah-to.
      The important thing is to get people using them.

      Good news: I have bought bottles of cold medicine (“cold” as in “the common cold”) that had the dose written in metric. They even came with metric-only dose cups, and IIRC the instructions said to measure only using the provided cup. Yes, this was in the U.S. The bad news is, the bottle size was in “hard” fluid ounces, which didn’t make sense as the number of doses per container was not an integer.

    • Karl,

      You may find this of interest:


      There is no problem with an automated factory working completely in SI. It is the old Luddite small ma & pa shops that cling to a mess. They struggle to make a profit, but don’t seem to want to make any change that would reduce or eliminate wastage. It is always someone Else’s fault for them struggling, mostly foreign competition.

      I have observed that no American company can be 100 % USC. There is always some degree of metric usage. Store bought products can be labelled in USC but can be hidden metric. When you go to put things together and parts don’t line up precisely because one is trying to mate round millimetre with rounded inch, time is wasted with rework, filing and grinding to make parts fit.

      Products that operate differently at different temperatures are tested and performance given per degree Celsius, yet, ovens and other heating devices maybe in Fahrenheit only or both, even if the specs are in degrees Celsius. I have personally test materials with different temperatures and found that ovens often set to wrong temperatures damage the material and shorten its life, but no one seems to care as long as it survives the warranty period. Of course if you tell someone the temperature is wrong, you get that silly, dumb retort: “But, we been doing it this way for 100 years and never had a problem”.

      But when foreign competitors enter the neighbourhood and despite some higher labour costs in the home country, they are able to sell your customer a better product at a lower rate, then all of those wastages do add up. But you may as well be talking to the wall to get a small ma & pa shop to change or to make improvements. They will simply keep going in their bliss until one day they try to pull into the parking lot only to find the gates paddocked and a for sale sign on the gate.

      PS. There is no such word as metrIFication. It is metrication. There is no IF in metrication.

      • Re:Metrication vs metrification
        What is bothers me the most is that this isn’t the first time I made the error!

        Wikipedia has it both ways.

        I was aware that there are a lot of industrial hoses moving metric – garden hoses seem stuck in the past (positive feed back loop) world-wide. There is a type of tubing connector where instead of a fitting, you just shove the end of a tube in – Something like this could actually end up replacing the garden hose connector.

        I disagree with “It is the old Luddite small ma & pa shops that cling to a mess” – I run a small shop – I get jobs from large companies full of legacy units. Ever heard of Boeing?

        All companies – large and small alike – are risk adverse – for good reasons. Changing anything is a risk – and if a change in units costs money – or screws up an order, someone will get blamed. CYA is actually more important at large companies than small.

        I use metric hardware in my designs – and feel free to do so because I’m the boss. If I worked for a larger company, I would have to get permission to make the change. Hard to get – if it isn’t broken – don’t fix it etc etc…

        Realize that positive-feedback is the central element of overcome – it effects everyone. I tell someone it is 10degC out and they say “yes, but what does that feel like?” they don’t know because they haven’t used it and they won’t use it because they don’t know it. Rinse and repeat.

  3. I suppose the centimeter is also part of the cgs system (as is the gram). However, the SI allows the use of any prefix with any unit, including the centimeter. If you are so sure it is deprecated, please quote chapter and verse from the SI Brochure.

    Of course “cc” is an incorrect symbol, spell out the words in full or use cm³ (section 5.1, final paragraph). The cgs units that are deprecated are the specially named units (section 4.1 and table 9) such as erg, dyne, poise, and several others.

    The micron is a 20th century unit, explicitly reaffirmed in a 1948 resolution of the CPGM (Appendix 1 of the SI Brochure) and was not deprecated until 1968, eight years after µ became a prefix.

    Finally, the liter is not strictly an SI unit, but is accepted for use with the SI (Table 6). Some authorities prefer cubic measure, cubic decimeters and cubic centimeters, to the liter and milliliter, even if they accept both (SAE TSB003, the SAE metric practice guide). In 1964, the CGPM reiterated the liter was a special name for the cubic decimeter.

    If you wish to argue one choice is preferred and another is only acceptable, that is fine. I do not think you should proclaim as “unacceptable” things that the SI Brochure accepts. Of course that means reading it and considering it before writing the blog. I understand “holier than thou” but when it comes to the SI, I don’t understand “holier than the CGPM.”

    • How do you expect a busy medical worker to type that superscript 3?

      They also type micrograms as “mcg”, because it’s too hard to type Greek letters. Remember, these people have jobs to do.

      Actually, I can’t help but wonder why handwritten prescriptions don’t have quantities shown in words, like the dollar amount on a check.

      • as cm^3. ug is also an acceptable representation of µg and only an idiot would confuse it with mg.

    • The “stere”, being exactly 1 cubic meter, would be more “SI-like” than the liter* (which would thus be one millistere):


      Sometimes, one wonders why they abandoned “good” original metric units, like this one…

      * The liter, being based on the deci- prefix, is less elegant in a purely SI-based context, so to speak.

  4. Since the US doesn’t have a Weight & Measures Act, it would be a moot point to have a Measurement Coordinator. Such a person would be to make sure the legal units are in all aspects of life. Some would see such a person as the metrication police.

    Does such a person exist in a foreign country that is competing against US interests and does that person give the foreign country and added trade advantage?

    We all know the US is a dying empire heading nose first into the abyss. All of these little nasty nuisances are all part of the movement towards destruction. It won’t be until after the demise is past that the surviving masses will be kicking themselves for not trying to fix the problems while they still had a chance.

    Best to speak out, but to let the cycle complete itself and for the next empire to correct the mistakes the present one is making. The Luddites though won’t be around to experience it.

  5. We have a good set of comments here among like-minded persons. What we need is to have it all done in an SI manner in a single book, which exists, namely Dennis R. Brownridge’s book Metric in Minutes: The Comprehensive Resource for Learning and Teaching the Metric System (SI).

    For those who don’t have this book, it is Strongly recommended you get a copy, which will well be worth whatever it happens to cost.

    [Note to Maven: Look at the way “which” is used in what is written here, which is completely correct. You (and many others) seem to use it repeatedly instead of “that”, which leads to good prose that [not which!] becomes annoying…]

Comments are closed.