Corroboration Sample Program (CSP)
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What is the CSP?
CSP Test Method for 2023
Technician Participation Requirements
Notification of CSP Testing
Scheduling a CSP Appointment
CSP Testing Process (Day of the Test)
Results Evaluation & Retesting
Certification Suspension & Reinstatement
What is the CSP?
The statewide Corroboration Sample Program (CSP) is an integral part 23 CFR 637 B (see Caltrans IAP), more specifically 637.207.a.2.ii which states, “Testing personnel shall be evaluated by observations and split samples or proficiency samples.” Caltrans, through the METS Independent Assurance Program (Caltrans IAP), established the CSP not only to meet the requirements of 23 CFR 637 B, but also to ensure consistent and reliable test results from all qualified technicians statewide. By annually requiring active technicians to perform testing on control samples (samples of known properties), Caltrans IAP can evaluate the technician’s ability to provide reliable and accurate results. The intended outcome of the CSP process is to improve technician testing abilities and to bring uniformity to materials testing on all Caltrans projects.
CSP Test Method for 2023
For 2024, Caltrans IAP has selected CT 202 – Sieve Analysis of Fine and Coarse Aggregates (Fine Gradation) for CSP evaluation. If you hold current certification in this test method, please contact your regional IA Staff (IA Staff Regional Contacts) to set an appointment for CSP testing.
- Past Test Methods used for CSP evaluation:
- 2023: CT 227 – Evaluating Cleanness Value of Coarse Aggregates
- 2022: CT 202 – Sieve Analysis of Fine and Coarse Aggregates
- 2021: CT 217 – Sand Equivalent
Technician Participation Requirements
Each year the CSP will identify a test method for evaluation. Technicians that are currently certified in the identified test method must participate in the CSP testing. However, if the test method is included in a Joint Training and Certification Program (JTCP) module and the technician will be attending the JTCP module in the same year as the CSP evaluation, the technician will be exempt from the CSP testing. Technicians that fail to participate in the annual testing will be suspended in the test method under CSP evaluation.
CSP testing must be conducted in a laboratory that is accredited in the test method identified for evaluation. If the lab does not hold the accreditation, but a technician needs to maintain the certification, the technician will need to arrange testing at an alternate accredited laboratory.
Notification of CSP Testing
Caltrans IAP will provide notification of CSP testing in advance of the evaluation year, typically in the final months of the previous year or the first month of the evaluation year. Individual technicians and their associated laboratories will be notified by email, which will include instructions and IA staff contact information. Since the Statewide Independent Assurance Database (SIAD) is Caltrans IAP’s primary source for contact information, it is imperative that technicians and laboratories assure their SIAD profile is accurate. The technician is responsible for scheduling an appointment with regional IA staff (IA Staff Regional Contacts) or the CSP coordinator at CSP@dot.ca.gov. After the initial notification, Caltrans IAP will send out quarterly reminder emails.
Scheduling a CSP Appointment
Technicians are responsible for scheduling a CSP testing appointment by contacting regional IA staff (IA Staff Regional Contacts) or the CSP coordinator at CSP@dot.ca.gov. An easy and convenient way to fulfill the requirement is to perform CSP testing in conjunction with the lab’s annual accreditation or during technician recertification of other test methods. Caltrans IAP recommends that technicians schedule this testing early in the year, as soon as the notification is received, so that the requirement is not forgotten during busier parts of the construction season. If the laboratory does not hold the appropriate accreditation, please arrange for conducting the testing at an alternate accredited lab prior to contacting regional IA Staff.
Testing Process (Day of the Test)
On the day of CSP testing, IA staff will arrive with a control sample and CSP reporting form. IA Staff will verify the technician’s identity then provide the sample, reporting form, and a verbal explanation of the process. The technician must have the appropriate equipment available with visible calibration decals where required. IA Staff may, as time permits, examine the laboratory equipment and/or witness the technician performing the test procedure and calculations. CSP testing is open book, so the technician may use the test method itself for guidance.
Upon completion of testing, calculations, and reporting, IA Staff will collect the split sample (if required) and the CSP reporting form. If IA Staff does not witness the testing, then the technician must report results to IA Staff and the CSP Coordinator (CSP@dot.ca.gov) within 2 business days of receiving the sample.
Please note: Only the designated technician can perform the testing. Alternate technicians cannot perform the testing on behalf of the designated technician. If Caltrans IAP obtains evidence that an alternate technician has been employed to conduct the testing, both the technician and laboratory risk suspension in all qualifications due to submission of fraudulent test results.
Results Evaluation & Retesting
Upon receipt of the CSP reporting form, Caltrans IAP will compare the technician’s test results to the IAP’s results on the same control sample lot. A “Degree of Corroboration” will be determined based on the test method under evaluation. For previous and current CSP testing years (2021 – 2023), the degree of corroboration and respective rating is shown for each test method in following table:
CALTRANS IA CORROBORATION TEST RESULTS
| CT METHOD | DESCRIPTION OF TEST PROCEDURE | DEGREE OF CORROBORATION* | ||
| GOOD | FAIR | POOR | ||
| 227 | CLEANNESS VALUE | ≤ 3 |
4-6 | ≥ 7 |
| 202 | SIEVE ANALYSIS (% Passing) | |||
|
≤ 2 | 3-4 | ≥ 5 | |
|
≤ 2 | 3 | ≥ 4 | |
|
≤ 2 | 3 | ≥ 4 | |
|
≤ 1 | 2 | ≥ 3 | |
| 217 | SAND EQUIVALENT | ≤ 3 | 4-5 | ≥ 6 |
*Degree of corroboration is the absolute value of the difference between the tester's result and the IA test results.
The technician’s CSP requirement will be considered complete once they receive a "Good” or “Fair” degree of corroboration. If the technician receives a “Poor” result, then the technician will need to test another sample provided by Caltrans IAP. The retesting must be witnessed in its entirety by IA staff. If the technician receives a poor degree of corroboration on the retest, they will be required to retest a second time. If failing to produce a good or fair result on the second retest, the technician will be suspended in the CSP test method under evaluation.
Certification Suspension & Reinstatement
If the technician opted out of CSP testing or failed to produce “Good” or “Fair” results after initial testing and 2 retests, they will receive a Notice of Action letter from Caltrans IAP detailing the conditions of suspension in the test method. The technician will be suspended until their certification expiration date, at which point they must go through the requalification process, including written and practical exams. To reinstate the certification before expiration, the technician must follow the appeals process as defined in the Caltrans IA Manual.
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