A. To start an ILS program with ASTM, the technical contact for the study must first register a program. To register a program, select the following link: http://myastm.astm.org/CUSTOMERS/ils.cgi. After selecting "Register a new Interlaboratory Study", you will be prompted to enter the appropriate information for your ILS. Shortly after the program is registered, the ASTM ILS staff will contact you to begin providing support. Registration of an ILS program ensures full administrative support from the ILS team.
A. When registering an ILS, it would be helpful to know which test method(s) will be included in the study, the materials or samples to be tested, the names of the supplier(s), the distributor, the number of replicates to be reported, and the name of your committee's statistical support person (if available). You will also need a copy of the standard test method or draft procedure. (ASTM will supply a copy of the standard test method to you if needed.) Please fill out the registration with as much information as you have and then submit to ASTM. If you are not sure of all the details for your study, ASTM can assist you in designing your study.
A. Yes, before you register an ILS program you will need to register a work item. (You will be asked for this information on the first page of the ILS registration.) A Work Item (WK) may be a new standard or a revision to an existing standard that is under development by a committee. The Work Item notifies the public that work is being done to revise a standard or to write a new one. ASTM publishes the Work Item descriptions in the interest of openness, as well as to solicit input from interested stakeholders who may not be members of the committee. To learn how to register a work item select the following link http://www.astm.org/ISP/PDFS/WorkItemReg.pdf.
A. Often used during the standard test method development, a ruggedness test is a screening procedure for investigating the effects of variations in environmental or other conditions in order to determine how control of such test conditions should be specified in the written description of the method. For example, the temperature of the laboratory or of a heating device used in the test may have an effect that cannot be ignored in some cases but may be much less important in others. In a ruggedness test, deliberate variations in temperature would be introduced to establish the allowable limits on control of temperature. A ruggedness test is done before a pilot test to determine the variables that will need to be considered in the study.
Once all of the controllable variables in your test method have been considered and addressed in the standard, it is strongly recommended that a pilot test be conducted. Before investing considerable laboratory time and expense in the full scale ILS, it is usually wise to conduct a pilot run in at least two laboratories, with one or two material(s) for several reasons:
A. For guidance on the number of laboratories refer to E691 Under no circumstances should the final statement of precision of a test method be based on acceptable test results for each material from fewer than 6 laboratories. This would require that the ILS begin with 8 or more laboratories in order to allow for attrition.
For guidance on the number of samples refer to E691 An ILS of a test method should include at least three materials representing different test levels, and for development of broadly applicable precision statements, six or more materials should be included in the study.
For guidance on the number of replicates refer to E691 The number may be as small as two when there is little danger that a test unit will be lost or questionable test results obtained, or as many as ten when test results are apt to vary considerably.
A. No, participants of the ILS do not need to be members of ASTM. Participants however should be familiar with the testing that is being completed.
A. Yes, as long as each data set is generated by a laboratory with its own set of environmental conditions, calibrations, and equipment conditions and is then compared to other laboratories with their own set of variables, the separate testing site requirement is met. To promote a normal distribution of data, it is recommended that no more than half of the participating labs come from any one organization.
A. Yes, an ILS should still be completed even if the recommended labs are not available. It is possible to generate a precision statement with less that six participating laboratories. The bottom line is that some precision information is preferable to no precision information.
A. Yes, ILS can assist in finding labs. First a lab solicitation will be sent to the committee looking for volunteers and then if more labs are still needed, ILS will reach out to the industry. Participants do not have to be ASTM members to take part in the study.
A. Once a program is registered with ILS, we prefer to collect the data from the labs. We have an online data report form that is sent out via an email to the lab participants. In the email, a hyperlink is provided which leads to a private webpage for that lab. After entering their data into the form the lab would select the submit button and the data will be sent directly to ASTM. Once all of the labs have submitted their data to ASTM, ILS is then able to run the data through ASTM's ILS Statistical Software. When we are ready to generate the research report, the data will be pulled directly from the software.
A. ILS is happy to assist with any data from studies previously completed. To get the process started, please register a program by selecting the following link: http://myastm.astm.org/CUSTOMERS/ils.cgi. After selecting "Register a new Interlaboratory Study", you will be prompted to enter the appropriate information for your ILS. Shortly after the program is registered, the ASTM ILS staff will contact you to begin providing support. Once the program is registered, please send the raw data to ILS@astm.org referencing the standard designation and ILS number (given to you once the ILS program is registered and submitted).
A. Once a round robin has been completed and the information has been balloted into the test method, the data shall be submitted to ASTM to be kept on file as a research report. A number will be assigned to the research report and a footnote will appear in the precision and bias section of the test method referencing the specific research report.
A. ASTM has funds available to assist with purchasing samples, sample preparation and distribution. After a proposal of costs is presented, ASTM will work with the committee to determine how much assistance can be provided. ASTM gratefully acknowledges the analyzing laboratories and the technical contacts for volunteering their time to the ILS efforts.
A. Yes, when balloting a new test method, repeatability is required in the precision and bias section. Per the ASTM Form and Style Manual Section A21.2.2 Every test method shall contain a statement (1) regarding the precision of test results obtained in the same laboratory under specifically defined conditions of within-laboratory variability (repeatability conditions). To produce repeatability conditions, one lab should test a range of samples numerous times. The recommended amount of replicates is as many as 10-20.
A. Per the ASTM Form and Style Manual Section A21 , precision and bias is required in a test method.
A21. Precision and Bias (Mandatory)
A21.2 Statement of Precision (Mandatory):
A21.2.1 Precision is the closeness of agreement between test results obtained under prescribed conditions. A statement on precision allows potential users of the test method to assess in general terms its usefulness in proposed applications. A statement on precision is not intended to contain values that can be duplicated in every user's laboratory. Instead the statement provides guidelines as to the kind of variability that can be expected between test results when the test method is used in one or more reasonably competent laboratories.
A21.2.2 Every test method shall contain a statement (1) regarding the precision of test results obtained in the same laboratory under specifically defined conditions of within-laboratory variability (repeatability conditions), and (2) regarding the precision of test results obtained in different laboratories (reproducibility conditions). Use a statement such as the following:
Precision — The repeatability standard deviation has been determined to be (insert the test values and corresponding repeatability values). The reproducibility standard deviation has been determined to be (insert test values and corresponding reproducibility values).
A. Per the Form and Style Manual Section A21.2.2:
Every test method shall contain a statement (1) regarding the precision of test results obtained in the same laboratory under specifically defined conditions of within-laboratory variability (repeatability conditions), and (2) regarding the precision of test results obtained in different laboratories (reproducibility conditions).
A. It is recommended that ruggedness testing and an interlaboratory testing program be completed before approval of a new standard test method. If a committee determines that a delay is necessary before conducting a full ILS to produce reproducibility, a temporary statement addressing repeatability conditions is permitted for five years. Included in the statement shall be language regarding the anticipated date of actual availability of reproducibility data.
A. The Form and Style for ASTM Standards mandates that all test methods contain a precision and bias statement. If a test method is discovered that does not contain this section, an evaluation should be immediately performed to determine the utility of the document and then steps should be undertaken to address the inclusion of a precision and bias statement.
A. To submit an item for ballot, simply log on to your "MyASTM" page, then select "Submit Item for Ballot" from the "My Tools" section on the left-hand side of the page. You will be prompted to enter the appropriate information. If you have any questions please contact your committee's Administrative Assistant.
RR:C21-1005 is an example of an acceptable research report.
A. A research report will be given a number once the ballot item to which it is linked passes the balloting process and is approved.
A. Footnotes for the precision and bias statement should be cited in the precision and bias section. There should be no footnotes for the precision and bias statement in the scope, reference documents or any other sections of the standard.