Quality Magazine

Other Dimensions: The Power of Zero

November 1, 2010
There is uncertainty in all things except for death and taxes.



When I was in school-admittedly some time ago-I was taught all about the number zero. Basically, it was about nothing and meant nothing. That was the easiest number I ever dealt with, but things have certainly changed since then.

Today, everyone seems to be on the zero bandwagon. They want all the bad things in life-real or imagined-brought to zero. No drugs-except those the government can tax-no noise, no accidents and the list goes on. They start with a zero tolerance policy for whatever they want changed and then expect government, of all people, to make it happen.

All of this might be possible if humans weren’t part of the problem, but in some cases, nature is the key player, and with time and government funding, there are some special interest groups who think they can sort nature out as well.

If some little kid whacks a playmate on the kindergarten playground, the system reacts as though they’ve caught a serial killer in the making. In no time he’s up before the principal, possibly the board, a committee, shrink or others who feed on the zero tolerance hysteria.

When it comes to anything chemical, it’s bad as far as these folks are concerned. The fact that some trace amounts of a chemical may be in everyone’s body naturally is ignored along with any science that shows there’s no harm to humans. Zero chemicals is good; anything else puts the world at risk by their reckoning.

I guess it was only a matter of time before this type of thinking hit dimensional metrology. It has, and whenever I encounter it, time and money are wasted.

A customer asked for information on gage block sets and demanded the best grade possible. When he got over the price shock, he still couldn’t understand why he had to pay all that money and the blocks would still have some “errors” in them. Zero errors is what he wanted but was not ready to pay it-even if it was possible.

Not being familiar with the company, I asked the obvious questions about what type of work they did and specifically why they needed such high levels of precision. It turns out they were a production machine shop and the blocks would be used to calibrate his micrometer and calipers. He didn’t indicate how he got error-free employees to do the work.

On too many occasions I get into discussions with customers over calibration reports which note our uncertainty on them. Too many assume it automatically means error and therefore our reports are not satisfactory. Then they send the item in question to another lab that doesn’t show uncertainty on their report and claim the size is a bit different from ours. As far as the customer is concerned, the other lab must be right because they don’t have this uncertainty business on their report.

Telling the customer that the only certainties in life are death and taxes won’t cut it for those who think a calibration laboratory is supposed to be at the top of the metrology food chain. They want the exact size without qualifiers of any kind. Telling them that one way out of this is to send the gage to NIST-the official legal authority for measurement-for calibration sounds promising to some until they find out two things: the cost of doing so and that NIST’s report will show a value for uncertainty as well.

Demanding zero is easy, getting it is impossible. Labs that play fast and loose with technical details cash in on this quest for zero and are more than willing to oblige with uncertainty claims of “...a couple of millionths” as to what their uncertainty is. Customers searching for zero rarely question such claims or ask for an uncertainty budget (if there’s one to be had) to see if they make sense. It can rapidly deteriorate into a situation where you have the con artist leading the blind, both of whom actually believe that zero is possible.

I suspect this problem will remain with us for some time until folks realize that there is uncertainty in all things except for the aforementioned death and taxes-representing zero life and zero money left after the taxes.