Canary seed: Determination of dockage

Definitions

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 chapter.

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.

Dockage not reported

Important: Dockage is not reported for

  • Canary Seed, Sample CW/CE Account Fireburnt
  • Canary Seed, Sample Salvage
  • Canary Seed, Sample Condemned
  • Unofficial samples declared as processed

Normal cleaning procedures

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:
    Carter dockage tester specifications
    Feed control No. 3
    Air control Minimum No. 3.5 (may be increased to remove the maximum amount of light weight material without removing whole seeds)
    Riddle No. 000 or No. 1 (for large seeds)
    Top sieve No. 4.5 round-hole
    Centre sieve Blank tray
    Bottom sieve None
    Sieve cleaner control Off
  2. Using a Boerner-type divider, divide the uncleaned sample to obtain a representative portion.
    Official samples shall be at least 1 kg.
    Unofficial samples shall be at least 1 kg.
  3. Turn on the Carter dockage tester.
  4. Pour the sample into the hopper.
  5. After the sample has passed through the machine, turn on the sieve cleaner control for two to three seconds to remove kernels lodged in the sieve.
  6. Turn off the dockage tester.
  7. Lightly snap the retainer rod of the aspiration pan to loosen material gathered on the air screen.
  8. The sample portion removed through the No. 4.5 round-hole machine sieve, is passed over a No. 4.5 round-hole hand sieve. Whole and hulled seeds remaining on top of the No. 4.5 round-hole hand sieve are returned to the sample.
  9. Using a Boerner-type divider, divide the sample to a representative portion of not less than 20g.
  10. Analyze the representative portion to determine the percentage by weight of admixture remaining in the sample.
  11. Analyze the representative portion to determine the percentage by weight of hulled seeds in the sample.
  12. Determine dockage using the list under Composition of dockage.

Composition of dockage

Dockage includes

  • material removed by the riddle
  • material removed by aspiration
  • material that passes through the No. 4.5 round-hole hand sieve (see Normal cleaning procedure No.8)
  • admixture handpicked from the cleaned sample
  • hulled seeds handpicked from the cleaned sample and recorded as a percentage of the gross weight of the sample

Optional analysis

Where a shipper requests special cleaning of a carlot of grain at a terminal 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.

Procedures

  1. Analyze the official sample.
  2. Record the following on inspection records:
    • percentage by gross weight to the nearest 0.1% and the grade of canary seed
    • percentage by gross weight to the nearest 0.1% and the grade of grain separable from dockage.
    • percentage of dockage

      Example:

      95.0% Canary Seed, Canada
      4. 0% Domestic Mustard Seed, No. 1 Canada Oriental
      1.0% dockage