This blog post, the fourth in Gilson's series on preparing for a technician certification exam, will focus on aggregates. As with the concrete and asphalt industries, state and federal agencies often require that those working on their construction projects have a higher level of expertise and experience, and hold a related technician certification. Those awarding contracts for road and other infrastructure projects, both government and private, may also require that the contractor awarded the project only use workers with a specific certification(s).
|Sampling Aggregates||T 2||D75|
|Reducing Samples of Aggregate to Testing Size||T 248||C702|
|Materials Finer Than 75-µm (No. 200) Sieve in Mineral Aggregates by Washing||T 11||C117|
|Sieve Analysis of Fine and Coarse Aggregates||T 27||C136|
|Specific Gravity and Absorption of Coarse Aggregate||T 85||C127|
|Specific Gravity and Absorption of Fine Aggregate||T 84||C128|
|Total Moisture Content of Aggregate by Drying||T 255||C566|
|Organic Impurities in Fine Aggregate for Concrete||T 21||C40|
The American Concrete Institute appears to be the only industry testing organization that offers national aggregate technician certification programs that are specific to testing operations. However, there are numerous other testing institutes, colleges and universities, industry associations, and state departments of transportation throughout the country that offer preparation materials and study resources, training, and/or testing. There may also be an industry-related company in your area that partners with a state aggregate association to provide classroom and hands-on lab training in preparation for the certification exam.
Gilson has an ongoing relationship with the Ohio Aggregates & Industrial Minerals Association (OAIMA) through which we host OAIMA's two-day training and testing sessions to prepare participants for the Ohio Level II Aggregate Technician Certification. This two-day training event is the same required by Ohio DOT of Aggregate Technicians, and meets Part 637 of the Federal Highway Administration (FHWA) Code of Federal Regulations regarding "qualified" sampling and testing persons.
Getting Started at the National Level
As stated earlier, ACI offers training and national certification examinations for Aggregate Technicians, many which go hand-in-hand with a number of concrete technician certifications. Note that with the progression of technician certification levels, there are additional standards that the applicant must be well-versed in. The links in the chart below take you to the respective ACI pages with these standards, as well as information on ACI study materials and more.
|Certification||ACI Definition||Certification Requirements/Recertification|
|Aggregate Testing Technician - Level 1 Job Task Analysis||"An individual who has demonstrated the knowledge and ability to properly perform, record, and report the results of basic field and laboratory procedures for aggregates.”|
|Aggregate Testing Technician - Level 2 Required Knowledge of ASTM/AASHTO Standards||"An individual who has demonstrated the knowledge and ability to properly perform, record, and report the results of advanced laboratory procedures for aggregates.”|
|Aggregate/Soils Base Testing Technician Required Knowledge of ASTM/AASHTO Standards||"An individual who has demonstrated the knowledge and ability to properly perform, record, and report the results of basic field and laboratory procedures for aggregates and soils."|
How to Find State Aggregate Technician Certification Training & Exam Programs
The FHWA's list of State Transportation Web Sites can get you started. Your state department of transportation (DOT) will have its own protocols on technician certification, specifically any required over and above federal regulations. Additionally, most if not all, state DOTs offer technician training programs and certification exams through the agency itself or in partnership with a state-approved entity. Bear in mind that a state DOT may also require a related concrete or asphalt technician certification, in conjunction with an aggregate certification, for those who work on its transportation construction projects.
In addition to state agencies, colleges and state universities often have technical programs geared to aggregate technician certifications. The information below can guide you further in knowing what to search for and what else to keep in mind:
- Search for aggregate technician certification on your state DOT website to see what exists. For instance, the Arizona DOT takes you to the Arizona Technical Testing Institute link, an arm of ADOT that oversees the scheduling, scheduling, study guides, examinations, list of certified technicians and more.
- Again, it's not uncommon for a state DOT to require an aggregate technician certification in addition to the asphalt or concrete certification. For instance, Colorado requires a Level-E Aggregate Certification of those who determine characteristics of aggregate used in asphalt mixtures for state projects. CDOT works in partnership with LABCAT, FHWA and other entities on certification; criteria include a demonstrated proficiency in aggregate sampling, sand equivalency, uncompacted void content of fine aggregate, specific gravity measurement of aggregate and more.
- Similarly, the Oregon DOT Certified Aggregate Technician (CAgT) program is a joint effort with the Asphalt Pavement Association of Oregon. State specifications require a CAgT to conduct quality control testing during the production of aggregate materials used in HMAC, EAC, PCC, base and shoulder aggregate, chip seals, oil mats and other highway applications. In addition to the Certified Aggregate Technician, they offer an expanded Greenhorn version of the certification program for those new to the industry.
- Many universities and technical colleges work cooperatively with their state DOT to provide certification training and testing. For instance, Michigan DOT offers Aggregate Certification Level 1 through Lawrence Technological University, while Wisconsin DOT and the University of Wisconsin-Platteville together offer three aggregate technician certification programs. Also searching universities in your state for aggregate technician certifications will help you find out what else is out there.
Additional Study/Prep Resources
There is no shortage of study guides, training programs with pre-tests, and exam sites from ASTM, ACI, National Highway Institute, state agencies or schools. A Google search of training materials for aggregate technician certification came back with several links, among which are:
- ASTM Aggregate Testing E-Learning Bundle (updated annually)
- National Highway Institute aggregates-related courses
- National Asphalt Paving Association, webinars and manuals
- ACI Bookstore, ACI University online learning, free online presentations on aggregates
Finally, when starting the process, do your homework prior to registering for any in-person or online training/CE courses from a private training entity. Some things to consider are:
- Does the training program encompass all ASTM/AASHTO standards required for the specific certification?
- Does it specifically prepare for the aggregate technician certification exam from a nationally-recognized testing agency such as ACI or a qualified agency in your state?
- Does it offer practice exams?
Missed the other four blogs in this series? Check them out: Construction Materials Testing: 7 Things to Know About Certification, The Road to Earning a Technical Certification in Concrete, Paving the Way to an Asphalt Technician Certification, and Soil Technician Certification for Materials Testing.