Special Purity Tolerances

To all Seed Analysts, Seed Technologists, and Seed Control Officials,

Now available is the updated AOSA Special Tolerances Computer Program (program) for automatically calculating special purity tolerances for seed mixtures with particle-weight ratios of 1.45:1 or greater using Tables 14D, 14E, and 14F (non-chaffy, chaffy, and super-chaffy seed mixtures, respectively) in the AOSA Rules, Volume 1.  The program will also return tolerance calculations based on Table 14B in cases when the components is 1.44:1 or less.  Funding for this updated program was generously provided by the American Association of Seed Control Officials (AASCO). 

This is a web-based application (no files to download).  Please read the User Manual before using the program as some data entry requirements and file save features have changed from the previous version of the program.  Please refer to AOSA Rules, Volume 1, Table 2A to determine whether a particular component is classified as non-chaffy, chaffy, or super-chaffy.   Please read Sec. 14.2a to determine which tolerance values to ‘generate’ when using the program.   The program will return the same tolerance value determinations as described in Section 14.2c in a format similar to the example provided in Table 14C.

Data you will need to supply when using the program:

  1. Label information (kind of seed, pure seed percentages).
  2. Results of second test (your test results).
  3. Number of seeds per gram (found in Table 2A) for each component.

Please e-mail Andrew Meyer (software developer) at meyer95864@gmail.com if you have any questions or comments about the program. 

Finally, to avoid confusion, you should delete any previously downloaded version of the program from your computer as the previous version did not allow for calculation of tolerances for mixtures containing super-chaffy species.

Good luck with your Special Tolerance calculations!

Purity Subcommittee Co-chairs – Gil Waibel (waibel@indianacrop.org) and Deborah Meyer (Deborah.meyer@cdfa.ca.gov)

Statistics Subcommittee Chair – Sabry Elias (sabry.elias@oregonstate.edu)


Program User Manual

Click here to download the full PDF.