Barley – Chapter 6 | Official Grain Grading Guide

Determination of dockage


Dockage is assessed 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.

Dockage is assessed in two stages.

  1. Follow Normal cleaning procedures, using the Carter dockage tester.
  2. Follow procedures for Cleaning for grade improvement. This cleaning can be done at any time after the cleaning assessment has been completed.

Dockage not reported


Dockage is not reported for samples grading

  • Barley, Sample CW/CE, Account Fireburnt
  • Barley, Sample Salvage
  • Barley, Sample Condemned

Normal cleaning procedures


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 # 5
Air control No. 6
Riddle No. 6
Top sieve No. 6 buckwheat
Centre sieve No. 5 buckwheat
Bottom sieve Blank tray
Sieve cleaner 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 2 to 3 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.


These are the normal settings. Ensure when you aspirate general purpose barley that you do not remove light weight barley from the sample.

If the aspirated material contains lightweight barley,

  1. Return the material to the sample.
  2. Reset the Carter dockage tester with a lower air setting to remove only lightweight dockage material.
  3. Pass it through the Carter dockage tester again.

8. Remove the aspiration pan.

9. Determine dockage, using the list under Composition of dockage.

Composition of dockage

Dockage includes

  • Material other than barley removed over the No. 6 riddle
  • Lightweight material removed by aspiration
  • Material that is removed by the No. 5 buckwheat Carter sieve
  • A maximum of 10% of soft earth pellets handpicked from the clean sample
  • Material removed by Cleaning for grade improvement

Cleaning for grade improvement

If the grade of a sample can be improved by additional cleaning, perform the cleaning and add the additional material to dockage. Cleaning for grade improvement can be done at any time after the cleaning assessment has been completed.

  1. After the cleaning assessment has been completed, examine the material to be removed and select your equipment according to the material you want to remove. See the table Cleaning for grade improvement—Barley for the list of equipment.
  2. Sieve the sample by hand, or pass it through the Carter dockage tester, depending on the material.
  3. Weigh the additional dockage and add it to the original dockage.


When you use a hand sieve, move the sieve from left to right 30 times, using a sifting motion. One time is one complete motion from the centre, to one side, to the other side, and back to the centre. The total distance from left to right is 20 cm, about eight inches.

Cleaning for grade improvement - Barley
Class Material to be removed Equipment Effect on composition of dockage
All classes Large seeds No. 6 buckwheat hand sieve Large seeds are
  • Seeds that do not pass through the No. 4.5 round-hole sieve
  • Grains other than cereal grains, such as peas, beans, corn flaxseed and domestic buckwheat
  • Ragweed and Tartary buckwheat
Assess material as dockage, provided the grade is improved and not more than 5.0% of barley is removed.
All classes Covered smut and false loose smut Carter dockage tester, set up for Normal cleaning procedures, with air control set to 7
Note: The material originally removed by aspiration is to be reconstituted back into the sample prior to cleaning for improvement.
If the percentage by weight of material removed is
  • Less than 2.0% of the gross weight of the sample, add to dockage
  • 2.0% or more of the gross weight of the sample, the sample is sent to the Chief Grain Inspector for review
All classes Attached awns Hand rub barley, Carter dockage tester for aspiration Removes awns. Separates detached awns from working sample. Awns removed to be included in dockage.
Hulless type only Wild oats, shrunken barley and rye grass No. 9x9 wire hand sieve For the select hulless grades, wild oats, shrunken barley and rye grass removed in the cleaning procedure is included in dockage.

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.


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


95.0% Barley, No. 1 CW

4.0% Domestic Mustard Seed, No. 1 CAN Oriental

1.0% dockage