ACBC Quality Control SAMPLING AND TESTING PROCEDURES

1. Standard Specifications The Producer is to perform all sampling and testing in accordance with current specification and procedures referenced in the NCDOT Standard Specifications Road and Structures.

2. Lot Size Quality Control lot sizes for 16” solid CMUs will be a plant run, or 100,000 units, whichever occurs first. Quality Control lot sizes for 8” solid CMUs shall be plant run, or 300,000 units, whichever occurs first.

3. Sampling The approval plant quality control individual is to obtain a sample from each lot. QC samples will consist of one sample per lot. The sample will consist of a minimum of ten units with the units randomly taken at a rate of two units per hour of production. Each unit will be marked with the time or day that it was samples. One unit from each hour of production will be used by the Producer; the other unit from that hour will be retained for use by the Department.

4. Check Samples If the test results for a sample indicate the material does not meet the specification requirements; a sample is to be immediately obtained by the Producer. Check samples are to be twice the number and taken in the same manner as the original samples. The samples are to be clearly identified and shared with one half tested by the Producer and the other half provided to the Department.
If the check sample indicated the material meets the specification requirements, the Producer is to record on the test report form what is felt to be the reason for the original failure and then may resume normal testing procedures.
If the check sample indicated the material does not meet the specification requirements, the Producer is to initiate an investigation to determine the cause of the failure. The investigation is to include a review of the sampling procedures, the equipment used in the production and the testing of the material and the testing procedures for the individual. If the cause can be attributed to one of the above categories, the Producer is to take corrective action to bring the material, equipment or procedure into compliance. The Producer is to then record the corrective action on the test report form and take another check sample after the corrections have been made.
If the investigation into the cause of the failure of the first check sample cannot be attributed to one of the above reasons, the Producer is to notify the Department, obtain a second check sample and continue the investigation into these failures and work with the Department to determine the cause of the failure.

5. If the second check sample indicates the material meets the specification requirements, the Producer may resume normal testing procedures.

6. If the second check sample indicates the material does not meet the specification requirements, the Producer is to notify the Department and stop the shipment of material. The Producer is to continue the investigation into these failures and work with the Department to determine the cause.

7. Test Procedures- Required test procedures shall be those required to meet the ASTM specifications referenced in Sections 1040-1, 1040-2 and 1040-3 of the NCDOT Standard Specifications for Roads and Structures except that concrete brick and masonry units shall be tinted red.

8. Sample Identification and Record Keeping It is critical that care be taken to properly label samples and record test data accurately.
Producer’s Quality Control samples are to be identified with consecutive numbers: QC-1, QC-2, etc. The samples are to be numbered consecutively for the entire calendar year.
All Quality Control test results are to be entered on an approved Quality Control Test Summary Form. The form shall indicate that Quality Control sample number, type and quantity of material represented by the sample.
Quality Control and Quality Assurance data is to be retained by the Producer for at least one year and made available to the Department upon request.
After a QC Test Summary Form is completely filled with data, a copy is to be given to the NCDOT Materials Inspector and the Producer is to retain the original. At such time when it becomes possible for the Producer to transmit data directly into the Department’s computerized database, or when the volume of QC tests does not result in at least one completely filled form per month, copies of these summaries are to be provided to the Department at a minimum frequency of once per month