Archive for the ‘Calibrations’ Category

Three Things To Know About The A2LA

Posted on: October 25th, 2014 by Dickson No Comments

Measurement - Dollar per hour

For those of you that need your temperature, humidity, or pressure devices calibrated, you will have to know about these guys. Here are three facts . . .

1. The A2LA accredits calibration laboratories like Dickson’s.

Getting A2LA accreditation isn’t easy, and requires an organization to be both skillful in, and dedicated to, quality assurance. Dickson and other calibration labs get accredited in ISO/IEC 17025, under a variety of measurement types, confirming that they adhere to the highly set standards of the A2LA.

2. The A2LA offers Industry-Specific Accreditation Programs.

Outside of laboratory and measurement uncertainty accreditation, the A2LA also offers accreditation in other fields, including:

  • Food and Pharmaceutical Testing
  • Clinical Field Testing
  • Air Emissions

For us here at Dickson, it’s all about measuring temperature and humidity. We are accredited as a calibration laboratory, and we can assure our customers that our own devices are accurate to a certain degree.

3. They offer accreditation and training.

Yup, you can take courses with the A2LA. These are specifically important for organizations that are looking for first-time accreditation, as the accreditation process can be a bit overwhelming for an organization that has never gone through a similar process. The A2LA offers training in quality assurance management systems, internal audits, root cause analysis, measurement uncertainty, and much more.


Replaceable Sensors: What are they, and how do they work?

Posted on: May 12th, 2014 by Dickson No Comments

What is it?

If you have a data logger or chart recorder, you probably have heard of calibration, and calibration has probably given you a headache. Calibration, or the process of checking and adjusting your measuring device to read temperature and humidity (or any variable, at that) more accurately is a difficult process. This process includes a lot of lost time and money, but is necessary to keep your data loggers or chart recorders reading temperature accurately.

There’s good news: We invented the Replaceable Sensor.

It takes the week long calibration process, and makes it much, much faster.


How does it work?

Like this . . . 


Is that it?

Yup, you just take off your new sensor, plug in the old one, and your device has been calibrated.


Okay, a bit more detail:

The key to our Replaceable Sensors, is that we separated the two functions of your data logger or chart recorder: measuring temperature and/or humidity and recording temperature and/or humidity.

Prior to the Replaceable Sensor, data loggers and chart recorders have measure the temperature and/or humidity of their environment internally, or inside the device, within the data logger or chart recorder.

With Replaceable Sensors, the temperature and/or humidity of your environment is measured on the Replaceable Sensor, which is separate from your device (see .GIF above).

So what does this mean for Calibrations?

When you calibrate a device, you are really only calibrating the part of the device that measures the temperature and/or humidity. The recording device (in the .GIF above, the big black box) has nothing to do with the calibration process. Formerly, this sensor would have been on the inside of the box, and our customers had to send their entire device back to us.

But no longer! Now, because the Sensor is separate from the data logger, the only thing that needs to be calibrated, is the sensor!

So now instead of packaging up your device and sending it back into us, and then waiting for us to calibrate it, you can just order a new sensor, pop the old one off, and put the new one on.

And to top it off . . . We include ALL the calibration data for the device on the sensor. You still receive your certificate, and you are still complying with auditors and regulations, in fact, better than ever before.


Last few things . . .

The benefits of Replaceable Sensors include:

  • Faster calibrations
  • More cost effective calibrations
  • Less downtime

It’s as simple as that!



More FAQ’s on Themometer Calibration

Posted on: May 12th, 2014 by Dickson No Comments

More FAQ's on Calibration

A few weeks ago, we answered four of our customer’s most frequently asked questions about temperature calibrations. We realized that only answering the four most common questions we’ve received doesn’t stop the confusion that comes with calibration and its many nuances. So, here are five more FAQ’s (and their answers, of course) taken directly from our interactions with our customers.

1. What is a 1-point calibration?

We get this question, in conjunction with the next question, a lot. Many calibration labs, Dickson’s included, offer 1-point calibrations. A 1-point calibration works like this: You send your temperature sensor into a lab for calibration. They check the devices accuracy, by comparing it with a standard (a temperature sensor that has been certified by NIST) LINK in a controlled environment. Then, after checking the devices accuracy at a specific point (usually chosen by you, or at a predetermined temperature point by the calibrating lab) they adjust to the devices readings to the correct temperature.

Is you’re a little lost, this might help to clear things up. Calibration and Adjustment are two separate terms, often used interchangeably to a fault by calibration labs. “Point” is a loose term used to define a specific temperature reading. For example, 32.7F is a point, and -5C is a point.

An example: A calibration lab determines that a device is reading 24F as 26F. So, the calibration lab adjusts the device two degrees, so that it now reads 24F. However, unless the calibration lab does a span adjustment, that device is adjusted down two degrees at 112F as well. This is also called a zero adjustment: it adjusts the readings of your temperature sensor across the entire scale.

2. What is a 3-point calibration?

A 3-point calibration is a 1-point calibration three times. These are sometimes called Span adjustments, and they are more tedious, yet make a device more accurate across a wider range of temperatures than a 1-point calibration. Instead of adjusting at only say, 2F at 72F, the calibration lab will adjust your temperature readings at for example: 12F, 72F,  and 112F by however much their calibration team determines the device is out of range at those temperatures.

3. Which should I get?

Depends on what you are monitoring. If you are monitoring over a wide range of temperatures, you will want the 3-point adjustment. Applications that usually monitor over a wide-range of temperatures include: food manufacturing, transportation, materials manufacturing, medical device manufacturing, and some warehouses. However, if you know that your environment will only range from a couple of degrees, a 1 point calibration may be all you need.

4. When does my calibration expire?

It depends. I know that is a lame answer, but it really does. What does it depend on? Your environment. After reading this, get up and go look at your data logger or chart recorder, and the environment around it. If your unit is in a “harsher” environment, you need to recalibrate more often. Dust, dirt, moisture, air particles all contribute to a device needing to me recalibrated more often. Also if you drop, kick, bump, or damage your device, it will need to be recalibrated more often. At Dickson, we say ALL devices should be recalibrated after 6 months to 1 year of their last calibration. If you are in a harsher environment, you may want to calibrate more often than that.

Temperature Calibration FAQ’s

Posted on: April 14th, 2014 by Dickson No Comments

FAQ's Calibration Photo

1. What is calibration?

In its most simple form, a calibration is a comparison between two measurements. The context and associated terms around calibration can get a little confusing. Before we get to those however, let’s back up. What is a comparison between two measurements? Think of it like this: You have a ruler that is 13 inches long, and you have another ruler that is 12 inches long. Each ruler is making a different measurement. You can compare one ruler to another to see which one is correct. That, in essence, is a calibration. Calibration labs (where calibrations occur) that calibrate temperature monitors (like Dickson’s!) put a unit under test and compare it with a device that can accurately tell you exactly how hot or cold a particular point is. To be more specific, it measures accurately all temperatures: 70F, 0C, 137F, etc. The key to calibrating an instrument is knowing that one device (a ruler, thermometer, gas gage) is more accurate than another device. The device that is more accurate, and can tell us exactly what 70F, 0C, 137F, etc. are, is called a standard. The device that is less accurate (our 13 inch ruler), is properly titled the unit under test. That is calibration. A standard and a unit under test being compared with each other.

2. Why should I calibrate?

You should calibrate because we assume you want to know your device is accurate. Back to our ruler metaphor. Rulers aren’t built to be 13 inches too often. But, as part of product quality, when you purchase a ruler, it would be nice to ensure it was indeed 12 inches. That is why you should calibrate. A temperature sensor is built, and you want to ensure its accuracy. When your temperature sensor is put under test, adjustments are made (like sawing off an inch of a ruler) if inaccuracies are found. Changes are made to the device to accurately meet the standard. These changes are called an adjustment.

3. Who says what is accurate?

So who says what is accurate? Who knows what 70F feels like? Who says a yard is a yard? It may seem arbitrarily argumentative, but it’s a compelling question. The answer is NIST. Who is NIST? NIST stands for the National Institute of Standards and Technology. This government agency creates and maintains standards of measurement for length, mass, time, etc. In regards to temperature, standards are sent in by their manufacturers, and those standards are told their accuracy. They then become a NIST standard, of which some variation you will find in Calibration labs.

4. Recalibration: what and why?

Sadly, yes, recalibration is a word. Let’s head back to our ruler metaphor one last time. Overtime, your calibrated 12 inch ruler may experience some wear and tear. Let’s say a piece of the ruler breaks off 8 months after you have it. You of course would just go buy a new ruler, instead of trying to fix that one. But let’s pretend that ruler was a really, really nice ruler, and the cost of making it 12 inches again was cheaper than buying a new one. What do you do? You send it back to a company certified by NIST, and then they compare it with a NIST ruler, which is exactly, or nearly exactly, 12 inches. If there is a difference, they add a little bit or subtract a little bit from your ruler. This happens to devices that measure temperature as well. Over time, due to natural wear and tear, temperature sensors lose their pinpoint accuracy. Specifically, environmental factors such as dust, dirt, and humidity can negatively affect a sensor’s accuracy. This is called drift. These devices probably won’t read 95F in a refrigerator that feels cool, but they may be off by a few degrees. For many applications, that matters. So, if you have a temperature monitor, you send it to a Calibration lab (like Dickson!) and we recalibrate, and then adjust your device for any differences with our standards.


Dickson’s Calibration Resume

Posted on: March 20th, 2014 by Dickson 1 Comment


Dickson Calibration