Ever wonder what is actually behind the all of the AASHTO re:source proficiency samples you receive? How long it takes to process them, or where samples are shipped? Previous articles on this topic include: "Not Just a Box of Rocks: An Introduction to the AMRL Proficiency Sample Program," "Proficiency Sample Ratings: Being Average Has Never Been So Good," and "Getting the Most Out of the Proficiency Sample Program: A Guide to Our Online Features and Tools." These articles can give you a great understanding of the program, but they only tell you what you need to know. Check out this infographic for a visual representation of our proficiency sample program.

If there is something that you’ve been dying to ask us, please let us know! We welcome any questions related to AASHTO re:source’s programs and services, and I will answer questions here in future newsletters. We may even use your questions as topics for future newsletter articles or webinars! For the inaugural column, here are some questions that we commonly receive about the AASHTO re:source Proficiency Sample Program.

Why can’t AASHTO re:source conduct on-site assessments only during the winter instead of during the busy construction season? We are swamped in the summer! On a related note, can you also please stop sending proficiency samples during the summer?!

Why doesn’t AASHTO re:source provide enough soil to properly perform ASTM D698 and D1557 on the proficiency samples? Why aren’t extra proficiency samples (XPS) available for emulsified asphalt and paint?

The AASHTO re:source Proficiency Sample Program (PSP) was created in March 1966 as a mechanism to evaluate testing competency by comparing the results of each participating laboratory to a large body of laboratories that are testing the same material. The program also provides laboratories with the means to check both the testing apparatus and the operator under actual testing conditions. Originally there were only four basic material types in our program. The program has grown extensively over the years and we now distribute fifteen different sample types each year.

Samples, data, ratings…Oh My! It can be a challenge to keep everything straight when enrolled in the AASHTO re:source Proficiency Sample Program (PSP). If your laboratory is already registered at www.AASHTOresource.org, you know how it can help you keep track of everything PSP-related. This article will cover some of the features on our website that will make participation in the Proficiency Sample Program a bit more manageable.

You just received an e-mail notifying you of low PSP ratings. This means that at least one of your scores was more than two standard deviations from the grand average, or that your laboratory did not submit data. (If you want more information on what ratings mean and how we calculate them, please review Proficiency Sample Ratings: Being Average Has Never Been So Good).

Thousands of laboratories in over 30 countries around the world participate in the AASHTO re:source Proficiency Sample Program (PSP). However, many of us never stop to think about the time, manpower, and logistics needed to produce and distribute these high-quality test samples. This article is intended to provide a better understanding of the complex process involved in proficiency sample production and analysis.

Why did I receive low ratings on the samples even though my results meet the precision estimate of the test method? That is bogus! Okay, I made up the “bogus” part, but you get the general idea. Why on Earth does AASHTO re:source disregard the precision estimate information when determining each laboratory’s proficiency sample ratings? It seems crazy, doesn’t it? Allow me a chance to explain the method to our madness.

In March 2017, the AASHTO re:source Proficiency Sample Program (PSP) gained accreditation for ISO/IEC 17043 General Requirements for Proficiency Testing. Accreditation to this standard means our sample program must adhere to specific international requirements relating to the operation of a proficiency testing program. These include requirements for the development and implementation of the proficiency testing program; homogeneity and stability testing; handling, storage, and packaging of materials; data analysis; management requirements; and corrective actions.

So you opened up your email notification to see that the latest AASHTO re:source proficiency sample ratings were just posted, you log into the website to view your ratings (Figure 1), and you see ratings of **, -5, -3, 5,4. You think to yourself, "I know that 4 and 5 are good, but what about the negative numbers? Those are below 3, so they must be bad... and what are the stars for? I doubt they're like the stars that my elementary school teacher used to give me... and what is this repeatability rating?"

In the latest episode of the AASHTO re:source Q & A Podcast, “Rolling Forward: Exploring the New Hamburg Wheel Track Proficiency Sample Program”, the hosts, with guests John Malusky and Ryan LaQuay, dive into the details of an exciting new addition to the Proficiency Sample Program (PSP). This episode is a must-listen for anyone involved in balanced mix design and testing and quality assurance, as it introduces this new sample type.

On season 3episode 20. we discuss how as AASTHO members, state DOTs can best use AASHTO re:source’s services.

Infographic: Here are the top ways you can use our Proficiency Sample Program.