Proposal for SAS Interlaboratory Test Program

[John D. Barnes]

SAS Interlaboratory Test Program

Solicitatiuon of Intent to Participate

Given that the worldwide SWmall-Angle Scatterinig community consists of 
something like 1500 practitioners, now seems like a good time to evaluate 
the performace of the measuring system represented by SAS techniques in 
an objective manner.

The generally accepted way to conduct such assessments of performance of 
a measuring system is through a suitably designed interlaboratory test 
program, commonly referred to as a "round-robin." This name persists in 
spite of the fact that it is usually not necessary to pass samples from 
one laboratory to another. Simple plots of results from a couple of 
specimens of suitably homogenmeous materials obtained in different 
laboratories are usually sufficient to demonstrate whether existing 
standards are adequate or need improvement.

This announcement is intended to determine whether the SAS community is 
interested in such an undertaking and to solicit suggestions that would 
aid in the design of such a program.

Please e-mail your replies to the following questions to me at 
john.barnes at nist.gov. I will collate the results, publish them, and 
consult with other members of the IUCr SAS Commission to determine what 
the next steps ought to be.

1. Would you be interested in carrying out measurements on specimens of 
between 2 and 4 materials and reporting thye results for tabulation?

2. If your answwer to question 1 is "yes" what materials would you 
suggest as being appropriate for use in an interlaboratory test program? 
What attributes of these materials should be measured?

In order to focus the discussion I would prefer to designj the program in 
a ammner that will let virtually any member of the SAS community 
participate. This implies that test scatterers should be isotropic, so 
that people with 1-d systems can characterize them. It would be desirsble 
to have materials that are suitable for use with both neutrons and 
x-rays. The amount of sample handling required for an end user to carry 
out the measurmenets should be minimized.

3. What methods (SAXS, SANS, USAXS, SALS, etc) would you be able to 
employ?

4. Can you suggest sources of suitable materials?

5. Would you be able to manufacture samples for one or more of these 
materials?

6. What test results should participants submiut? What particulars of the 
experiment should be included asauxiliary data to be submitted by the 
participants?

Thank You


Dr. John D. Barnes               email: john.barnes at nist.gov
Natl Inst of Stds and Tech       Voice: 301-975-6786
100 Bureau Drive, Stop 8544        FAX: 301-975-4977
Gaithersburg, MD 20899             URL: http://www.nist.gov/sas
                               or http://www.ctcms.nist.gov/~jdbarnes