Measures and mistakes due to our lack of the metric system

triptick

The scene when the Spinal Tap’s manager discovers the prop is MUCH smaller than he expected.

In a scene in Rob Reiner’s mockumentary, This Is Spinal Tap, the rock group’s manager (played by Tony Hendra) goes to pick up a piece of scenery that is meant to evoke Stonehenge in connections with one of the group’s songs. He indicates that he’s quite pleased with the model with which he’s been presented with until he finds out that it is the finished piece and not a model. He expected something 18 feet high, not 18 inches high.

The designer (played by Anjelica Huston) seeks to defend herself and pulls out the napkin she’d been given to work from to show that the specifications indicated 18″ by 18″. She’d done exactly as instructed.

Closeup of napkin with specifications

A zoom in on the napkin held in the character’s hand reveals the specifications she was given was, in fact, not 18 feet but 18 inches.

Within our measurement system, the difference between (“) and (‘)* is huge. In fact, the difference is 279.4 mm or 11 inches!

“Well,” defenders of our current measures might say, “that was done for comic effect and bears no relationship to the real world.”

I beg to differ by way of an example supplied to me by a coworker.

Her husband needed a metal bar fabricated and specified on the order “3/4″ x 3/4” x 1/2′ Long.” However, instead of getting a bar that was three-quarters of an inch wide and three-quarters of an inch thick and six inches long, he instead received a small block since the (1/2’), or a half foot, direction was read instead as part of an inch rather than part of a foot.

Shows the instructions

The instructions as provided to the fabricators.

Photo of small aluminum block.

Instead of a six-inch-long bar, he ended up with a block slightly smaller than an inch in all dimensions.

As if that isn’t confusing enough, the (“) and (‘) symbols can denote both lengths and durations. Thus, 5’ 4” could mean either five feet and four inches or five minutes and four seconds if there were no context indicating which measure was intended.

So, along with the many stumbling blocks of education and medicine, and other errors related to commerce, this particular vendor had to record the original order as a loss and make and send an item that actually conformed to what the customer had originally specified.

Such errors would be greatly reduced if orders were written in “mm” for the measures rather than in the easily mistaken (“) and (‘) units.

Thus, the order could have been written: “19.05 mm x 19.05 mm x 152.4 mm.”

A lot less ambiguous.

I wasn’t able to find any information on how frequently such errors are made, but if I only had to look to the office next to mine to find an example, can they be very far away from any of us in this country?

Close up of ruler with metric and customary units.

U.S. rulers often contain a confusing mix of whole, half, quarter, eighth and sixteenth units. Metric system rulers usually just mark on the whole (10) and half (5) counts.

In conducting research for this piece, I also came across information related to “how to read a ruler/tape measure.” One source went into detail about how to distinguish between the half- and quarter-inch marks on such tools. In contrast, metric system-based rules only have differing marks to help count the “fives” and “tens.”

As I continue to look, the more examples I find of how we’re making our lives more difficult since we don’t use the metric system exclusively in this country.

Have an example of confusion/problems you’ve encountered due to our lack of metric system adoption you’d like to share? Feel free to comment on this page or send an email to me at milebehind@gmail.com.

Stay tuned. Right now I’m researching our very early history with the metric system in this country. Luckily, prior to the last metric system push in the mid-1970s, our government put out a 200+ page document that goes into just such history. I’m now rereading it within the context of the book I’m writing.

Thanks for getting all the way down here.

Linda

* Note: Marks for feet and inches should always be indicated by straight lines, rather than by using quotation marks, which are usually curved. Did I have to look up how to make the straight lines to indicate feet and inches to write this article? Yes, yes I did.