Independent Assurance Samples (IAS) and the testing associated with those samples is a requirement of federal law. The federal definition for the independent Assurance sample process is "Activities that are an unbiased and independent evaluation of all the sampling and testing procedures used in the acceptance program."   The Federal Code does not specify a specific number of samples to obtain.  Nor does it say when or where. That decision is left to the state agencies.

Independent Assurance Sampling procedures

What are the goal the process and the procedure?

The Goals of IAS are to determine that the equipment used during any test, the testing procedures followed, and the technicians running the equipment are following the testing procedures correctly so that the results of the test are valid for the material. 

The Department procedures for IAS include the following:

A.                Yearly QARs of District laboratories to evaluate equipment calibrations and ODOT laboratory technician processes.

B.                 Yearly round robin testing for aggregate, asphalt and concrete.  District laboratories are part of this round robin process that also includes private aggregate, asphalt and concrete laboratories performing tests (whether quality control or acceptance) for the Department.

C.                 Random District notification for IA samples for specific material types that exceed a Central Laboratory determined Quantity.

D.                A yearly validation of each technician used by the Department will be targeted and performed whether they are internal technicians or a suppliers technicians. 

a.       The Central Laboratory understands that 100% cannot always be achieved but the initial target is to establish procedures that would theoretically cover 100% of the operating technicians for the year. 

                                                  i.      Each year a review will be made of the percentage and numbers, by district, and an evaluation will be made.

b.      For IAS testing of technicians, the year will be January 1 thru December 31 of each year.

Aggregate Technician IA

Each District is responsible for yearly IA testing of each technician performing gradation testing for S1069 certified suppliers in your district.  Use the following process to perform this:

1.      At the beginning of the season when you are pulling your first verification samples obtain a large enough sample to split and provide a split to the certified suppliers testing technician. This means this sample will do DOUBLE DUTY as both a verification and IA sample.

a.       Provide the technician with a reporting form for the gradation or establish a method they will document to you their gradation test results.

b.      In writing, define the time period they must provide you results by   This can be on the reporting form you provide (you could write in the date)

c.       Perform your own gradation testing and report those results in CMS as normal.  Create an 02 sample and define as IAS for INSPECTION TYPE

d.      When you receive the technician results create an 03, define as IAS and put in the technicians results. 

e.       Using the multi laboratory criteria for Precision and Bias in AASHTO T27 make a comparison between the 02 and 03. 

f.       If the results compare favorable place in the REMARKS of the 03 sample that

                                                  i.      Sample No. XXXXXX-02 was compared with No. XXXXXX-03 using T-27 criteria and the comparison was acceptable.

g.      If the results do not compare favorably an evaluation needs to be done to determine what the problem was.  The following is suggested:

                                                  i.      Check your own test results

                                                ii.      Check your own scales and sieves

                                              iii.      Discuss with your DET your test procedures

                                              iv.      If the items i, ii, iii are clear then again

1.      visit the company and pull another sample for the technician

2.      have the technician perform the test in front of you

3.      check for their scale records

4.      visually check their sieves.

                                                v.      If item iv finds issues notify the company of the problem and require, in writing, how the company is going to resolve the issue.

                                              vi.      In the 03 sample report the following:

1.      Sample No. XXXXXX-02 was compared with No. XXXXXX-03 using T-27 criteria and the comparison was not acceptable.  The following resolutions were made were taken ..

Examples would be

Equipment re calibrated and a new procedure set up

New equipment bought

Technician sent back to training

Technician retrained by company and validated by District.

h.      Upon completion of the IAS process Access the O drive O:\Construction\(IAS) Independent Assurance Test Reporting.

1.      Open the excel file named 2009  IA sampling report format 1-20-09.xls 

a.       [as each year changes the year at the beginning of the file will change]

2.      Access the Aggregate Technician worksheet and complete the required info

Asphalt Technician IA

Each District is responsible for yearly IA testing of each technician performing asphalt testing at asphalt plant supplying the district.  Use the following process to perform this:

1.      At the beginning of the season when you are starting monitoring on a project, use one of your split samples during monitoring as a DOUBLE DUTY sample also for IA. 

a.       Require the technician provide you all test data for the sample on the standard reporting form.

b.      In writing, define the time period they must provide you results by  

c.       Perform your own testing and report those results in CMS as normal.  Create an 02 sample and define as IAS for INSPECTION TYPE

d.      When you receive the technician results create an 03, define as IAS and put in the technicians results. 

e.       Using the split sample ranges defined in Appendix J make a comparison between the 02 and 03. 

f.       If the results compare favorable place in the REMARKS of the 03 sample that

                                                  i.      Sample No. XXXXXX-02 was compared with No. XXXXXX-03 using Department established ranges and the comparison was acceptable.

g.      If the results do not compare favorably an evaluation needs to be done to determine what the problem was.  The following is suggested:

                                                  i.      Check your own test results

                                                ii.      Check your own equipment is calibrated

                                              iii.      Discuss with your DET your test procedures

                                              iv.      If the items i, ii, iii are clear then again

1.      visit the company and pull another sample for the technician

2.      have the technician perform the test in front of you

3.      check for their equipment calibration records

4.      visually check their equipment.

                                                v.      If item iv finds issues notify the company of the problem and require, in writing, how the company is going to resolve the issue.

                                              vi.      In the 03 sample report the following:

1.      Sample No. XXXXXX-02 was compared with No. XXXXXX-03 using Department established criteria and the comparison was not acceptable.  The following resolutions were made were taken ..

Examples would be

Equipment re calibrated and a new procedure set up

New equipment bought

Technician sent back to training

Technician retrained by company and validated by District.

h.      Upon completion of the IAS process Access the O drive O:\Construction\(IAS) Independent Assurance Test Reporting.

1.      Open the excel file named 2009  IA sampling report format 1-20-09.xls 

a.       [as each year changes the year at the beginning of the file will change]

2.      Access the Asphalt Technician worksheet and complete the required info

Concrete Technician IA

Each District is responsible for yearly IA testing of each technician performing concrete testing at the district concrete sites. 

As this testing is not directly in the control of the personnel responsible to the DET a district wide process supported by the DCE will need to be set up.  If the district has a Concrete monitor IA duties are part of those functions.  If the district does not have a Concrete monitor then a separate person will need to be assigned concrete IA duties.

POSSIBLE ALTERNATIVE PROCEDURES

1.      Track each concrete technician and assign a District person responsible for doing side by side comparison tests with each field technician at the jobsite.

a.       Each tech would run air and slump

b.      Do tests and make comparisons as listed below for concrete techs.

c.       Perform reporting of results in CMS as listed below

d.      Report the technician on the Construction website IAS list of concrete technicians checked for the year

2.      District concrete monitor perform the IAS process similar to item 1.  (original goal of concrete monitors).  

a.       If the district has a monitor the coordination should be easier as they are involved in most of the pours; can track who and who has not been tested for the year.

b.      Can test, compare and report as part of the process (similar to item 1).

                                                  i.      Record results

3.      District track work every two weeks.  If concrete testers have not been IAS then pull them together on first job and perform IAS comparison tests.

a.       Still need to designate the primary tester to make the reports and log the results

b.      Report the technician on the Construction website IAS list of Concrete technicians checked for the year

c.       Every two weeks re check the list versus the Construction website IAS list of concrete technicians perform the tests for those not listed.

4.      Project Engineer checks the Construction website IAS list of concrete technicians

a.       For any technicians doing concrete work for the PE not on the list

                                                  i.      Do side by side comparison tests with each field technician at the jobsite.

                                                ii.      Each tech would run air and slump

                                              iii.      Do tests and make comparisons as listed below for concrete techs.

                                              iv.      Perform reporting of results in CMS as listed below

                                                v.      Report the technician on the Construction website IAS list of concrete technicians checked for the year

No matter the procedure used to determine how you track and assure the IA testing is done the actual testing procedure and comparison should be as follows.  When performing the IA testing

a.       Assure you are sampling testing from exactly the same load (wheel barrel) as the ODOT technician. 

b.      To keep this simple you need to first witness the technician performing the test procedure(s) on their equipment.  Then you run the same tests on your equipment with the split sample concrete.

c.       Record the results for both the technician and your tests. 

d.      Find out from the technician the sample ID for the concrete.

e.       Create an 02 sample put in the your results and define as IAS for INSPECTION TYPE

f.       Create an 03 put in the technicians results and define as IAS. 

g.      Using the following split sample ranges to make a comparison between the 02 and 03.

a.       Air test within 1.0%

b.      Slump test 1 inch 

h.      If the results compare favorable place in the REMARKS of the 03 sample that

a.       Sample No. XXXXXX-02 was compared with No. XXXXXX-03 using Department established ranges and the comparison was acceptable.

i.        If the results do not compare favorably an evaluation needs to be done to determine what the problem was.  The following is suggested:

a.    Check your own equipment is calibrated (scale and pot) 

b.    Check the technician equipment is calibrated.  Maybe the only way will be to re-calibrate.

c.    You should have already known if the technician actually did the test correctly because you witnessed it.

k.      If b or c notify the Project Engineer, the DET and the DCE of the problem and require how the issues will be resolved (whether equipment or technician).

l.        In the 03 sample report the following:

1.      Sample No. XXXXXX-02 was compared with No. XXXXXX-03 using Department established criteria and the comparison was not acceptable.  The following resolutions were made were taken ..

Examples would be:

Equipment re calibrated and a new procedure set up

New equipment bought

Technician sent back to training

Technician retrained and validated by District.

j.        Upon completion of the IAS process Access the O drive O:\Construction\(IAS) Independent Assurance Test Reporting. 

k.      Open the excel file named 2009  IA sampling report format 1-20-09.xls 

a.       [as each year changes the year at the beginning of the file will change]

2.      Access the Concrete Technician worksheet and complete the required info

Nuclear Density Technician IA

Each District is responsible for yearly IA testing of each ODOT technician performing nuclear density testing at a districts project sites. 

The District Construction Engineer, or designee, will need to set up a district wide process to assure all ODOT technicians who are testing that year are IA checked at least once during that year.   Two processes/methods are suggested:

Process 1

5.      Track each person with the gage to the jobsite and perform side by side testing to compare results of a test.

a.       The IA tester and the gage operator will run a standards tests for their gage

b.      The gage operator being tested will run a density and moisture test by setting up the site and running a direct transmission test at a six inch depth in the prepared hole.  (The IA tester will witness each operators procedures without violating the safe zone requirements.)

                                                  i.      Record the results 

c.       The IA tester (with the standarded gage) will run a density and moisture test in the same hole after waiting at least 10 minutes after the gage operator ran the test.

                                                  i.      Record the results 

1.      The IA tester will compare the two sets of results and an acceptable comparison is based on the Density and moisture values being within the acceptable ranges listed below.

d.      Record the test results in CMS for gage operator and IAS tester as listed below including whether the comparison was acceptable or not

e.       Report the gage operator information into the Excel file that is stored on the Construction website by accessing

                                                  i.      the O Drive;

                                                ii.      select the Construction sub directory

                                              iii.      select the (IAS) Independent Assurance Test Reporting sub directory

                                              iv.      Open the excel file named 2009  IA sampling report format 1-20-09.xls 

1.      Fill in the required information in the excel file under the tab Nuclear Density Technicians 

2.      [as each year changes the year at the beginning of the file will change]

Process 2

6.      Determine all gage operators who will be performing nuclear gage testing for the year.  At a site near the district, bring all those technicians together with all the districts assigned gages

a.       Each gage operator will run a standards test

a.       The gage operator being tested will run a density and moisture test by setting up the site and running a direct transmission test at a six inch depth in the prepared hole

                                                  i.      Record the results 

b.      All other gage operators (with the standarded gage) will run a density and moisture test in the same hole after waiting at least 10 minutes after the gage operator ran the test.  (The IA tester will witness each operators procedures without violating the safe zone requirements.)

                                                  i.      Record the results 

c.       Finally the IA tester (with the standarded gage) will run a density and moisture test in the same hole after waiting at least 10 minutes after the last gage operator running the test.

                                                  i.      Record the results 

d.      The IA tester will make a comparison of each operators results with the IA testers results for density and moisture. Favorable comparisons will be when the differences in the results fall within the acceptable ranges listed below

                                                  i.      Record the test results in CMS for gage operator and IAS tester as listed below including whether the comparison was acceptable or not

e.       Report the gage operator information into the Excel file that is stored on the Construction website by accessing

                                                  i.      the O Drive;

                                                ii.      select the Construction sub directory

                                              iii.      select the (IAS) Independent Assurance Test Reporting sub directory

                                              iv.      Open the excel file named 2009  IA sampling report format 1-20-09.xls 

1.      Fill in the required information in the excel file under the tab Nuclear Density Technicians 

2.      [as each year changes the year at the beginning of the file will change]

When recording results of the IA tester and the gage operator(s) in CMS do the following: 

1.      Report the results as an IA testers results as an IAS sample, sample number XXXXXX-01

2.      The gage operators test results will be recorded and reported as sample number XXXXXX-02 

3.      The IA operators comparison of the results between XXXXXX-01 and XXXXXX-02 will be listed in the REMARKS of the 02 sample.   If the operators procedures were correct and the test results compare favorably place:

a.       Sample No. XXXXXX-01 was compared with No. XXXXXX-02 using Department established ranges as follows:

                                                  i.      Density - Two operator results in the same hole difference not greater than 1.0 lbs.

                                                ii.      Moisture two operator results in the same hole difference not greater than 1.2%.

4.      If the operators procedures or the comparison of test results did not compare favorably then in the 02 sample REMARKS report the following:

a.       Sample No. XXXXXX-01 was compared with No. XXXXXX-02 using Department established criteria and the comparison was not acceptable.  The following resolutions were made were taken ..

Examples would be:

Equipment re calibrated and a new procedure set up

New equipment bought

Technician sent back to training

Technician retrained and validated by District.

Remember to also complete the IA testing excel file by accessing the O drive and following the instructions listed in one of the two (2) processes listed above.

Procedure during the year for Checking if a technician has met IA requirements

Whether it is aggregate, asphalt, concrete or nuclear density, check the spreadsheet on the O  at O drive O:\Construction\(IAS) Independent Assurance Test Reporting to see if the technician you are working with has been IAd. 

If the technician has been IAd then just continue on with your work.  If the technician hasnt been IAd then notify the DET and see that the IA tests are performed following one of the procedures listed above. 

Central Laboratory Quality Assurance Procedures

At least Quarterly checks will be made of the excel file on the O Drive to see how each district is progressing in IA testing and posting of those technicians.  Districts will be notified of their status and how they compare to other districts.

District Laboratory Testing technician IA

For Aggregate and Asphalt Technicians in each District the district will perform IA as follows:

Aggregate

All technicians who will either perform aggregate, asphalt or concrete cylinder testing will obtain round robin samples from the central laboratory and report their results to the lab. 

Departmental Random IA sample procedures

1.         When the Department determines an IAS sample will be required based on the requirements of the below IAS sampling frequency table. 

5.                  A material has to have been sampled for acceptance.  Tests run on that material sample to determine acceptability and test values are reported for that material. 

3.         When an IA sample is required based on item 1, a second sample of the originally sampled and tested material in item 2 needs to be obtained.  The IAS sample will be obtained by a different technician, qualified to take the sample and perform the test, than the acceptance sample (item 1 sample)

4.         The IAS will be sampled from the same location and have the same tests performed as the original acceptance sample  (based on material type, the Department may determine that not all tests performed on the acceptance sample will be run on the IAS).  The testing of the IAS will be performed by a different technician than the acceptance sample

5.         Compare the results of the Acceptance sample and the IAS to determine if the IAS provided acceptable results.

a.         The test results should be reasonably close for the IAS results to compare favorably     

i.          Reasonably close may be determined as follows:

(1)        Use the criteria established under the Aggregate, Asphalt or concrete technician sections to determine reasonably close conformity

ii.          If test results compare favorably, the IAS process is complete.:

(1)                Input the IAS results into CMS

a.       Create an 02 copy of the acceptance sample and make it IAS.

(2)                Input your test results form the IA sample

(3)        In the REMARKS portion for the IAS sample

 (a)       Input the acceptance sample number the IAS sample was compared to

(b)       Input that the IAS sample compared favorably and the reason.

b.         If the sample test results dont compare favorably? 

i.          An investigation is required to determine why.  This investigation will include

(1)        Were the acceptance sample and the IAS both sampled properly? [Were the correct procedures followed]

(2)        The equipment that was used was calibrated OR is calibrated. 

(a)        A check of both the IAS equipment and the acceptance sample equipment to verify correct.

(i)         equipment includes everything.

(3)        Review technician procedures.

(a)        The IAS testing technician will obtain a sample of the same material type and watch the technician who ran the tests on the acceptance sample.

ii.         Determine what part of the investigation caused the un favorable comparison.

(1)        Require correction of the problem and verify the corrections have been made before continued sampling, use of equipment, or the technician continues to perform tests.

iii.         Document the final results of the IAS process

(1)       Input the IAS results into CMS by creating an 02 sample of the acceptance.

(2)        Input the test results from your IA sample

(3)        In the REMARKS portion for the IAS sample

(a)       Input the acceptance sample number the IAS sample was compared to

(b)       Input that the IAS sample did not compare favorably and the reason(s).

An IAS is not an acceptance sample for a material.  A result outside of specification limits or an unfavorable comparison will not change the materials original acceptance status.

Department Random IAS sampling frequency

301, 302, 304, 442, 446, 448, 451, 452, 511, 842 materials

OMM will determine projects for IAS sampling based on the table below.  The District will perform IAS sampling and Testing, evaluate the results and report in CMS.

The queries for IA samples for a project are based on the equaling or exceeding the Bid quantity in the following table.  Where there were multiple construction items of the same type, the quantities were combined for this query.  The DET only needs to follow the IA sample process on at least one of those construction items for that project.

When the monthly IA sample list includes a project and construction item in your district, assure at least one IA sample is taken for that project.

The District Engineer of Tests (DET) is responsible for the sampling, testing, comparison and final determination for all independent assurance samples that are required based on the above table.  The DET may use the central laboratory as a source of information and testing, if required.

Other Departmental Methods for evaluation Technicians  

QPL and Certification Programs

For certification programs OMM requests random project samples for guardrail, rebar, and fencing samples by e-mail on a bi-weekly basis. Districts will pull samples from the field and provide those samples and copies of the shipping paperwork to OMM for testing.

OMM is responsible for testing, comparison and final determination for all independent assurance samples that are required for certification programs. 

For QPL programs OMM will request random samples based on the following:

A.                 OMM has the capabilities to test the actual materials within the laboratory

B.                 The actual material has true testing requirements

a.       QPL products may be a combination of elements that are more certification than actual piece by piece material sampling and testing. 

C.                 Reported problems with materials in the field

OMM is responsible for testing, comparison and final determination for all independent assurance samples that are required for the QPL items the Laboratory requests. 

Round Robin Processes

Yearly round robins are performed by central laboratory on aggregate, asphalt suppliers and on precast and prestressed concrete suppliers performing compression testing.  

Districts also participate in these round robins.  All results are posted on the Department inter-office websites.

YEARLY REPORTING

District End of Year reporting Documentation

1.                  Find all IAS samples for the year

2.                  Create a table showing what sample was compared with what sample (this should be the same sample number but 02 or 03 etc.

3.                  Define which compared favorably and which didnt

4.                  For the ones that didnt copy the REMARKS on what was found and the corrections and put that into separate table of sample numbers that didnt compare well

For the Aggregate, Asphalt, Concrete and Nuclear density technician IA create a final table that shows for each the percent of favorable compared and not favorably compared

Provide the report by January 31 following the IA year.

Overall Departmental Report

A yearly report will be issued by the Department.  This report will include all IAS samples and their general resolution.  To prepare this report the District and OMM sections will submit to the Administrator of the Office of Materials Management a yearly report of all for IAS they were responsible for.  Submit the report by 1-31 of each year.

That district format will be as defined in the section above.  Section report formats will be as agreed to by the Administrator.