Soybeans – Chapter 20 | Official Grain Grading Guide

Determination of commercially clean

Dockage is not assessed on soybean samples that meet the commercially clean specifications set out in the Soybean Export Shipments section. All samples must be analyzed to determine if they meet commercial cleanliness standards prior to dockage being assessed. The analysis of samples which are clearly not commercially clean may consist of a visual assessment. For example, if there is no doubt that a sample contains more than 0.2% of roughage material then dockage will be assessed using the procedures defined under Determination of Dockage. Where there is any doubt regarding whether the sample is commercially clean the sample must be analyzed using the procedures, and applying the specifications, listed below.

  1. Using a Boerner-type divider, divide the sample to obtain a representative portion.
    • Official samples shall be at least 1 kg.
    • Unofficial samples shall be at least 1 kg.
  2. Place approximately 250 grams of the sample at a time on the No. 8 round hole sieve.
  3. Move the sieves from left to right 30 times using a sifting motion. One complete motion is approximately 10 cm from the center to one side, back to the center, approximately 10 cm to the other side and back to the center.
  4. Separate broken soybean from the other material passing through the No. 8 round hole sieve. Note: Soybean hulls are included in the material other than broken soybeans.
  5. The material other than broken soybeans is weighed and the percentage calculated to determine if it meets the commercially clean specification for material other than broken soybeans through the No. 8 round hole sieve. (Column 1 of the commercially clean specification table)
  6. Handpick the entire sample remaining on top of the No. 8 round hole sieve for any roughage material and hulls.
  7. The roughage and hulls remaining on the No. 8 round hole sieve is weighed and the percentage calculated to determine if it meets the commercial clean specification for roughage and hulls. (Column 2 of the commercially clean specification table)
  8. The percentage of roughage and hulls and the percentage of material other than broken soybeans passing through the No. 8 round hole sieve are added together to determine if the total meets the commercially clean specification. (Column 3 of the commercially clean specification table)
  9. The broken soybeans passing through the No. 8 round hole sieve are weighed and the percentage calculated to determine if it meets the commercially clean specification. (Column 4 or column 5 of the commercially clean specification table.

Should the percentage concentration of any factors determined in steps 1 through 9 exceed the specifications set out in columns 1 through 5 of the commercially clean specification table the sample will be considered to be not commercially clean.

Dockage will be assessed on samples determined to be not commercially clean using the procedures outlined under Determination of Dockage.

Definition of commercially clean specifications for soybeans
Grade name 1 2 *3 (1+2) 4 5
Material other than broken soybeans through the #8 round hole sieve. Roughage and Hulls Total roughage, hulls and material other than broken soybeans through the #8 round hole sieve. Broken Soybeans through the #8 round hole sieve
Not direct exports Direct exports
Soybeans 1,2,3,4,5 Canada 0.1% 0.2% 0.2% 0.75% 1.0%