DIME Overview & Definitions

What is DIME?

DIME is the acronym for Data Interchange for Materials Engineering. DIME is a web application developed by the California Department of Transportation, Materials Engineering & Testing Services (METS) to allow material testing laboratories the ability to easily submit sample information and test data to Caltrans' database via the internet.


In the near future, Caltrans' specifications will require non-Caltrans organizations submit quality control test results to Caltrans via the internet. DIME was developed to facilitate this submission process. DIME provides material testing laboratories an easy-to-use web application to upload data, view data, edit data and verify data. A goal for DIME is to efficiently store and share material test data for California transportation projects and is not meant to be used by external laboratories as a laboratory management tool. Each external laboratory should save and back up their files locally.


DIME provides a number of advantages over manually submitting test results via email or parcel post. For instance, DIME checks if submitted data meets data requirements. If data requirements are not met, the data is not accepted. Secondly, after preliminary data is submitted (by laboratory staff for example), a user with data-verifying privileges (the laboratory manager for example) can verify accuracy of the sample information and test results prior to final publication. Thirdly, test data is protected and can be easily shared if other laboratories choose to do so. Finally, email notifications can be sent out to designated persons for actions performed on data.

Submitting Data

DIME allows the user to input data manually. This means the user types in sample information and test data in a form on the DIME website and clicks a "Submit" button when all required fields are filled out and valid. The data uploaded to DIME is private and not publicly shared.

How Does a Company/Laboratory Sign up for DIME?

You can submit your request for a DIME account online. Please see the instructions found on the Sign In / Registration page.

Definitions used in DIME


A Caltrans construction project usually identified by an EFIS or DEA/EA number.

Material Types

Material Types in DIME refer to the kind of material that is sampled and subsequently tested.

For example, Aggregate, Asphalt Binder, Concrete, Hot Mix Asphalt, Methacrylate and Paint are all Material Types supported in DIME.


A Sample in DIME refers to a subset of a bigger lot or batch of material that is to be used on a Caltrans construction project. What constitutes a Sample in DIME depends on the type of material and the reporting requirements.

Typically, the Sample is taken from a single unique lot or batch so that results from testing point to the characteristics of the larger lot, batch, etc.

In DIME, all Samples in DIME need to be associated with a Project and must be of a DIME-supported material type.

DIME Sample ID

The DIME Sample ID is a unique identifier generated automatically by the DIME system that is based on the date the sample was taken and a system generated date‐based sequence Number. Examples below:

Sample Taken Date Automatically Generated Sequence Number Resulting Sample ID
2024-06-23 1 2024-06-23‐1
2024-06-23 2 2024-06-23‐2
2024-06-23 3 2024-06-23‐3
2024-06-24 1 2024-06-24‐1
2024-06-24 2 2024-06-24‐2
Specimen / Replicate

The concept of a Specimen or Replicate is not necessarily used in DIME, but it is important to distinguish a Specimen or Replicate from a Sample.

Normally, a Specimen or Replicate refers to one or more portions of the same Sample that multiple tests can be performed on.

For example, from a single lot and heat, 1,000 bolts are produced to be used on a Project. Various tests such as tensile strength, hardness and proof load testing are required to be performed on this lot and heat so 10 bolts are taken as a Sample for testing. In this situation, each of the 10 bolts is referred to as a Specimen. From those 10 Specimens, bolts are taken for each of the different kinds of tests.

Typically, the test results for each Specimen are reported under the same Sample record.

Test / Test Method

A Test Method (or simply "Test") in DIME refers to a procedure performed on Samples of Material Types to assess properties of the material. These procedures are typically described in documents developed by standards setting organizations such as ASTM, AASHTO, Caltrans (for California Test Methods), etc.

Examples of Test Methods implemented in DIME include, ASTM C39 v17a, AASHTO T201 v15, AASHTO T269 v14, CTM (California test Method) 217, etc.

Testing Lab

The laboratory or other organization that the Tester belongs to. Testing Labs are typically required to be independently accredited to perform the test.


The individual that performs a Test on a Sample. Testers are typically required to be independently certified to perform the Test.

Sampling Lab / Organization

A Sampling Lab or Organization refers to the lab, company, organization or unit that physically obtained the material Sample from the supplier, producer, job site, etc.

Test Result

Result values are obtained after a Tester performs a Test. These Test Results are recorded in DIME so that they can be shared with appropriate Project personnel. What Test Result values are required to be reported are normally found in the document which describes a Test Method.

Test Card

A Test Card in DIME refers to the form used to input Test Results. The term is a leftover from long ago when Test Results were recorded and maintained on paper cards.

Published / Verified Test

A Published Test in DIME refers to test results that have been reviewed and made public. Typically, test results are available immediately after running Tests on Samples and submitting the results, but the user has the option to set a date that the Test Results are to be made available to the public. Published and Verified Test Results can be searched on and viewed by any visitor to DIME. Only Caltrans staff can Publish test results.

Verified Tests are very similar to Published Tests but only users from non-Caltrans organizations can Verify test results.


The DIME Test ID is a unique identifier generated automatically by the DIME system to identify a test performed on a sample. A sequential test number will be appended to the DIME Sample ID to generate the DIME Test ID. The format and a few examples of the DIME Sample ID and DIME Test ID are shown below.

DIME Sample ID Test Sequence Number Resulting DIME Test ID
2024-06-23‐1 1 2024-06-23‐1‐1
2024-06-23‐1 2 2024-06-23‐1‐2
2024-06-23‐1 3 2024-06-23‐1‐3
2024-06-23‐2 1 2024-06-23‐2‐1
2024-06-24‐1 1 2024-06-24‐1‐1
Environmental Product Declaration

An Environmental Product Declaration, or EPD, is a declarative document that quantifies environmental information on the life cycle of a product to enable comparisons between products fulfilling the same function. The EPD methodology is based on the Life Cycle Assessment (LCA) tool that follows ISO series 14040.

Caltrans uses the DIME system to accept EPDs for Projects.

METS Representative

The METS representative assists the resident engineer with management of source-inspected materials. The METS inspector acts as the eyes and ears of the METS representative and resident engineer at the material's source.

METS Representatives are assigned to a Caltrans District and is based on the type of contract the Project falls under.

Organization Manager

An Organization Manager in DIME is a role that has privileges to manage the data submitted and reported out from the organization. The DIME Organization Manager is also the point of contact for adding, changing or removing DIME users from their organization.


A Vendor in DIME is a supplier of material to be used on Caltrans' projects.