The Truth About Leak Test Equipment Specifications

These days it seems uncovering the truth and gaining access to unbiased factual information can prove challenging.  If you’re a Product Development Engineer, Quality Engineer, Manufacturing Engineer, where can you go for accurate sensor-based NDT test method information you can trust?  Where can you get the truth about leak test equipment specifications?

While relying on a blind internet search might seem like the best place to start.  Consider this, you can find information on the internet about every topic you can imagine.  But how can you tell if the information is accurate?  How do you know that the information you get isn’t being influenced by sales goals or marketing strategy?  

Unless you have substantial experience with an extensive variety of applications in several industries, it can seem almost impossible to determine what specification information isn’t “too good to be true.”  As someone fits the above description, I feel qualified to offer perspective on technical specifications as it applies to leak testing.

Where technical specifications can fall short.

In any sensor-based NDT test methods, including leak testing the accuracy of sensors will inevitably have bearing on the test results. I think we can all agree on that. But sensors alone are never the whole story. It’s the accuracy of the entire leak testing SYSTEM that needs to be considered.

Too good to be true is almost always true!

There are actually some telling ways to identify sensor accuracy reports that seem like they are “too good to be true” because they ARE “too good to be true”.

Any NIST traceable sensor would always be calibrated by an independent calibration device that has four or five times the accuracy of the sensor being calibrated.  There are a few questions you can ask the equipment manufacturer/supplier to be sure you’re looking at unbiased data:

• Can you get access to the published and third-party independently verified calibration standards?
  
  
• Can you watch a calibration at work in the instrument manufacturer’s facility? If such a visit is off-limits—this is a red flag and indication you should consider other options.
  
  
• Is the accuracy ONLY for the sensor or if it is for the entire system that the sensor works within? You should keep in mind that there is not much point of having the most precise sensor if the manufacturer has not considered A/D conversion, resolution, and software validation?

If a “best in class” sensor inside your instrument and is integrated it into an automatic system, what happens when the system designer has allowed loose tolerances or substandard part handling and sealing into the system? This is where meaningful, factual and truthful discussions about your application should begin. Believe me, these discussions can sometimes be uncomfortable and unveil less-than-ideal information. But, as they say, sometimes the truth hurts.

I recently received a call asking if we could achieve measurement accuracy a full order of magnitude higher than that used by the majority of medical device manufacturers whom USON has helped with leak testing solutions for over half a century. If I was going to be flip, I’d say "Sure, we can get you that accuracy if you want each test cycle to last about a week.”

However, I don’t want to be flip.  For obvious reasons, this doesn’t bode well for the customer, or for Uson.  There is far too much at stake for the customer, consumers of their products, and for Uson to make claims that are not backed by data.

Instrument specifications that make claims such as accuracies taken out of real world contexts are nothing more than works of fiction for managers who want comfort rather than objective sourcing of best-in-class NDT methods that align with the laws of physics.

Uson can help!

As you embark on research for your next project, consider the points and advice presented here.  These suggestions can help you sort through the noise and get down to the truth more quickly and identify the best leak testing solution for your application.

If you need additional assistance with your upcoming projects, Uson’s leak testing experts can help. Contact us directly or reach out to your local Uson representative.