Dockage is assessed and recorded to the nearest 0.1%.
Dockage is defined under the Canada Grain Act as “any material intermixed with a parcel of grain, other than kernels of grain of a standard of quality fixed by or under this Act for a grade of that grain, that must and can be separated from the parcel of grain before that grade can be assigned to the grain.” Dockage is removed by following the cleaning procedures described in this section of the guide.
The sample as it arrives is referred to as the uncleaned or dirty sample. Its weight is the gross weight of the sample. Dockage is assessed on the gross weight of the sample.
▲ Important: Dockage is not reported for samples grading
▲ Important: Wear gloves and a mask to handle any samples that you suspect may contain hazardous substances.
1. Set up the Carter dockage tester as follows:
| Feed control | #7 #9 for large-seeded varieties |
|---|---|
| Air control | #5 #7 for large-seeded varieties |
| Riddle | none |
| Top sieve | none |
| Centre sieve | blank tray |
| Bottom sieve | none |
| Sieve cleaner control | none |
2. Using a Boerner-type divider, divide the uncleaned sample to obtain a representative portion.
3. Sieve portions of approximately 250 grams at a time.
4. Nest the No. 24 or No. 18 round-hole sieve over one of the following sieves, depending on the size of the seeds:
5. Handpick from the material remaining on top of the No. 24 or No. 18 round-hole sieve all whole or broken sunflower seeds. Return them to the portion passing through the No. 24 or No. 18 round-hole sieve and remaining on top of the No. 10 round-hole or No. 6 buckwheat sieve.
6. Pass through the Carter dockage tester the material which has passed through the No. 24 or No. 18 round-hole sieve and remains on top of the No. 10 round-hole sieve (or the No. 6 buckwheat sieve).
7. Handpick whole sound sunflower seeds from the material removed by aspiration and return them to the cleaned sample.
8. Using a Boerner-type divider, divide a portion of approximately 250-g.
Note: At this point the handpicked 250-g portion should be used to determine test weight.
9. Handpick the 250-g portion for inseparable material including broken hulls. Determine what components of the handpicked inseparable material will be considered dockage as directed under Composition of dockage.
10. Determine dockage, using the list under Composition of dockage.
Primary samples with dockage levels up to 5.0% are considered commercially clean.
Where a shipper requests special cleaning of a carlot of grain at a terminal or transfer elevator, and the elevator manager agrees, dockage material will be analyzed for the presence of grain. The percentage and grade of any grain contained in the dockage will be reported and elevator stocks will be adjusted on the basis of the analysis. Agreement of the shipper and unload elevator must be conveyed to the CGC in writing prior to the analysis being performed.