ACI Aggregate Testing Level 1 Technician Certification

Certification Dates


December 5-6, 2019 - Wayne County




Introduced by ACI in 2007, the Aggregate Testing Technician (ATT) – Level I Certification was developed to certify laboratory technicians in the sampling and testing of concrete aggregates. 
Certification assures owners, specifiers and other interested parties that the testing of aggregate is conducted by the qualified laboratory personnel. 

The course covers the following AASHTO aggregate test methods:
T2 Sampling of Aggregates
T11 Materials Finer than No. 200 Sieve
T85 Specific Gravity & Absorption of Course Aggregate
T255 Total Evaporable Moisture Content by Drying
T248 Reducing Samples of Aggregate to Test Size
T27 Sieve Analysis of Fine & Coarse Aggregates
T84 Specific Gravity & Absorption of fine Aggregate
T21 Test for Organic Impurities in Fine Aggregate

Course Overview

On day one, the eight AASHTO standards are reviewed through a combination of classroom and laboratory instruction. On day two, students complete written and performance exams demonstrating their knowledge of the test methods. The ATT certification meets the requirement of ASTM C1077 “Standard Practice for Laboratories Testing Concrete and Concrete Aggregates for use in Construction.” 


The “open book” written exam consists of 100 multiple choice questions divided into eight sections. Each section covers an individual AASHTO standard. Passing requires a minimum overall score of 70% AND a minimum score of 60% on each individual standard. Students have two hours to complete the written exam. 

For the performance exam, students are evaluated on their ability to correctly perform the required procedures for each of the AASHTO standards.

Note: Students successfully passing both the ACI CST and ACI ATT certifications will also receive ACI's Laboratory Testing Technician - Grade I Certification.