Sampling systems handbook and approval guide

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8. Conventional sampling (Non-cross-stream)

8.1 General

Samples to be forwarded to the CGC for analysis that are obtained by a conventional sampling method outlined in Chapter 8 must be accompanied by a CGC “Sample Record and Information Slip”—Form I-120 (Section 8.2). The record must clearly state the method and the equipment by which the sample was taken and any conditions present that may have an influence on the sampling process.

Samples obtained by conventional methods that are to be presented to the CGC for official certification analysis must:

• be obtained by authorized personnel using CGC procedures and appropriate sampling equipment.
  1. Authorized personnel include CGC personnel or third party agencies accredited by the CGC.
  2. CGC procedures include all CGC directives, methods, policy bulletins, and memorandums.
  3. Appropriate sampling equipment includes the conventional sampling devices listed herein.
• be of the prescribed quantity (Section 1.4 – Types of official samples and Section 1.5 – Types of unofficial samples),
• be properly identified including the method by which it was taken,
• be handled securely without being mixed with other grain samples or bulk grain, and,
• include, where required for moisture analysis, a minimum sub-sample of 300 grams in an airtight container alongside the primary sample.

Samples presented to the CGC for analysis that are taken by anyone other than the CGC or an accredited third party will be only eligible to receive a CGC Submitted Sample Certificate Type 1 or Type 2. The sampling methodology used to collect the sample may be referenced on the certificate.

The maximum number of railcar or container sub-lot samples that may be combined for analysis and inclusion on one CGC certificate is 10.

Sampling and sample-reducing equipment

Hand scoop

The hand scoop (Figure 8.1) (see chapter 9 for applicable certification) is a sampling device consisting of a rigid material scoop attached to a 50-100 centimetre handle which is stiff and durable. The sample collector capacity must be a minimum of 50 grams and not more than 200 grams.

Figure 8.1: Hand scoop

Bag trier

The bag trier (Figure 8.2) (see chapter 9 for applicable certification) is a sampling device consisting of an elongated core shaft that has a slotted opening along its length. The slot opening or sample trough must measure a minimum of 19 mm (¾ inches).

Figure 8.2: Bag trier

Grain probe

The grain probe (Figure 8.3) (see chapter 9 for applicable certification) is a sampling device consisting of an outer sleeve and an inner tube with perforations at regular intervals along its length. It is used for sampling bulk grain in railway cars, trucks, containers, bins, or holds of ships. Probes vary in length from 1 meter (40 inches) to 3.65 meters (144 inches). Grain probes may be of “open handled or compartmentalized” construction.

Figure 8.3: Grain probe

Pneumatic probe sampling unit (truck probe)

A pneumatic probe sampling unit (Figure 8.4) (see chapter 9 for applicable certification) is a hydraulic powered sampling system that may be used to sample trucks, railcars, or barges. Through a series of hydraulic pistons, a sampling probe is inserted into a bulk lot of grain. On reaching maximum probe depth, a pneumatic recovery system is activated to retrieve the sample from the bulk grain lot and to deliver it to a sample container in the inspection area.

Note: Open-ended vacuum/constant suction probes (Figure 8.6) are not approved for CGC use.

Figure 8.4 Pneumatic probe sampling unit

Figure 8.5 Compartmental and core tip probes

Figure 8.6 Open-ended vacuum/constant suction probes

Boerner-type divider

A Boerner-type divider (Figure 8.7) is a gravity-operated dividing apparatus that reduces a grain sample. The sample is placed in the upper hopper and released by opening the valve located in the hopper throat. The sample flows downward and is evenly dispersed over a cone with evenly spaced separations. The divided sample is rejoined in two grain streams which empty into two collecting pans at the bottom.

Figure 8.7 Boerner-type divider

8.2 Form I-120 – Sample record and information slip

Every sample and every separate portion of a sample must be properly identified as to the sampling process and the grain it represents on the Canadian Grain Commission’s Sample Record and Information Slip – Form I-120. Grade determining conditions such as insects, large stones, heated grain, moths or excreta that may be apparent in the lot during sampling but not in the sample must be included as comments on the sample ticket. Information from the Sample record may be referenced on CGC certification documents.

8.3 Probe sampling patterns – bulk grain

Vessels

A vessel hold cannot be manually probe sampled to determine overall quality. Probe sampling of a vessel hold may only be done to determine the quality parameters of portions of a grain lot previously sampled by automatic means to confirm grain quality for discharge or to determine grain quality to conclude a discharge.

Open top containers - approximately 20 tonnes

Probe size: 1.6 metre min.

No. of probe samples: 5

Probe where indicated by o.

Note: If the indicated probes do not provide an adequate sample size, additional probes should be taken where indicated by *

Hopper car – approximately 85 tonnes

Probe size: 1.6 metre min.

No. of probe samples: 8 per 4-compartment car

No. of probe samples: 9 per 3-compartment car

Probe as indicated by arrows.

Hatch top container – approximately 20 tonnes

Probe size: 1.6 metre min.

No. of probe samples: 4 minimum

Probe as shown for a two-hatch container.

Note: Take as many probes as possible and record any limitations on Form I-120 – Sample Record and Information Slip

Flat Bottom Trucks

Probe size: 1.6 metre min.

No. of probe samples: 8 minimum/single trailer, 10 minimum/truck and trailer

Probe where indicated by .

Hopper bottom trucks

Probe size: 1.6 metre min.

No. of probe samples: 8 minimum/single truck, 10 minimum/partitioned truck or truck and trailer

Probe where indicated by .

8.4 Hand scoop sampling procedure

(Figure 8.1)

Caution: Sampling must be done in an area where the entire grain stream is accessible. All safety precautions must be adhered to in attempting to sample from a grain stream or near a moving conveyor.

• The minimum amount of sample required to be taken prior to any dividing down must be at least 4 times the amount of sample outlined in Chapter 1 – Sections 1.4 and 1.5.
• The maximum number of railcar or container sub-lot samples that may be combined for analysis and inclusion on one CGC certificate is 10.

Procedure:

1. The sampling frequency must be at least one sample selection per minute taken systematically throughout the transfer.
2. On commencement, insert the hand scoop into the grain stream at alternating points across the stream (left, middle, right). The scoop should be replaced into the grain flow “upstream” and overturned. While moving “downstream”, the scoop is turned to fill grain. Moving the scoop with the grain flow allows sampling of the appropriate location in the grain stream without splashing grain or overflowing the scoop.
3. Examine the increments for uniformity while sampling.
4. Combine the increment scoop samples in a sample container.
5. Reduce the sample to the appropriate size.
   • *If a moisture test is required, place the sample or a 300-gram portion of the sample in an airtight container with proper identification.
   • **A Boerner-type divider must be used to reduce “official samples”.
6. Complete a Sample Record and Information Slip (Form I-120) and include it with the sample.

8.5 Probe sampling procedure for sacked grain

(Figures 8.2 and 8.3)

Caution: Safety precautions must be adhered to while sampling stacked grain sacks.

• Sacked grain refers to grain in any type of bag or tote.
• The facility/requestor must provide personnel to move sacks as necessary.
• All sacks in the lot must be accessible.
• All sacks in the lot must be of the same product, weight value and identification.
• All sacks must be tagged or stencilled with lot number/identification.
• Lot information must be identified on the Sample Record and Information Slip (Form I-120).
• The minimum amount of sample required to be taken prior to any dividing down must be at least 4 times the amount of sample outlined in Chapter 1 – Sections 1.4 and 1.5.
• The maximum number of railcar or container sub-lot samples that may be combined for analysis and inclusion on one CGC certificate is 10.

Table 1 – Lot/sub-lot unit requirement

Item	Number of bags	Bags to be sampled	Totes
1	1 - 30	All	All totes must be sampled (maximum 300 totes per lot)
2	31 - 150	30
3	151 - 300	60
4	301 - 450	90
5	451 - 1200	120
6	1201 - 2000	200
7	2001 - 3000	300
8	3001 - 4000	400
9	4001 - 5000	500

Procedure A: Grain in bags

Bags are grain sacks generally weighing 50 kg or less.

1. Examine the lot and determine the number of bags (frequency) to be sampled and the quantity of sample required from each bag. (i.e. 4000-gram sample/120 bags sampled = 33.3grams/bag)
2. Select the required bags to be probed in a well distributed pattern.
   • *It is recommended that lower stacked bags be struck with the large end of the trier to relieve the pressure on the bag and prevent it from bursting.
3. With the slot opening of the bag trier facing down, insert the trier in between the fibres of the bag using a push-and-turn motion. Rotate the trier 180 degrees and tilt the trier handle downwards to allow some of the product to flow out of the bag. Retract the trier and readjust the bag fibres to close the gap. For official samples, a CGC bag patch must be applied over the probing site. Examine each increment for uniformity and ensure a suitable amount of sample is taken from each bag.
4. 4. Reduce the sample to the appropriate size
   
   • * If a moisture test is required, place the sample or a 300-gram portion of the sample in an airtight container with proper identification.
   • **A Boerner-type divider must be used to reduce “official samples”.
5. Complete a Sample Record and Information Slip (Form I-120) and include it with the sample.

Procedure B: Grain in totes

Totes are grain sacks generally weighing 250 kg or more.

1. All totes in the lot must be accessible and must be sampled.
2. The maximum number of totes in a lot or sub-lot is limited to 300.
3. After reaching maximum depth, open the probe.
4. Close the probe.
5. Extract the probe and release the sample onto a cloth, trough or into a sample container and examine it for uniformity. Based on the quality and quantity of sample taken by the probe, determine if multiple probes are required.
6. A minimum of 2 probes per tote is required.
7. Reduce the sample to the appropriate size.
   • * If a moisture test is required, place the sample or a 300-gram portion of the sample in an airtight container with proper identification.
   • **A Boerner-type divider must be used to reduce “official samples”.
8. Complete a Sample Record and Information Slip (Form I-120) and include it with the sample.

8.6 Probe sampling procedure for railcars or trucks

(Figure 8.3)

• Sample drop cloths or troughs must be of adequate length and free from holes or damage to allow for the visual inspection and the retention of the sample.
• The minimum amount of sample required to be taken prior to any dividing down must be at least 4 times the amount of sample outlined in Chapter 1 – Sections 1.4 and 1.5.
• The maximum number of railcar or container sub-lot samples that may be combined for analysis and inclusion on one CGC certificate is 10.

Procedure:

1. Complete the Sample Record and Information Slip (Form I-120) as much as possible prior to ascending any conveyance.
2. With the slots closed, insert the probe into the grain.
3. On reaching maximum depth, open the probe.
4. Close the probe.
5. Extract the probe and release the sample.
6. Repeat steps 2 through 5 until an appropriate number of samples have been collected. (Section 8.3 – probe patterns). Based on the quality and quantity of sample taken by each probe, determine if additional probes are required.
7. Check the sample for uniformity and note irregularities.
8. Combine the sample into a sample container.
9. Reduce the sample to the appropriate size.
   • * If a moisture test is required, place the sample or a 300-gram portion of the sample in an airtight container with proper identification.
   • ** A Boerner-type divider must be used to reduce “official samples”.
10. Complete a Sample Record and Information Slip (Form I-120) and include it with the sample.

Note: Probe sampling of a vessel hold is to be conducted only to reaffirm or conclude specific quality parameters of grain previously sampled by an automatic sampling system during or for a discharge.

8.7 Pneumatic truck probe sampling

(Figure 8. 4)

Caution: Pneumatic probe samplers must be operated by facility staff trained in the operation and use of the device.

• The minimum amount of sample required to be taken prior to any dividing down must be at least 4 times the amount of sample outlined in Chapter 1 – Sections 1.4 and 1.5.
• The maximum number of railcar or container sub-lot samples that may be combined for analysis and inclusion on one CGC certificate is 10.
• Sampling patterns outlined in Section 8.3 – Probe sampling patterns – must be followed for probe sampling of railcars and trucks.

Procedure:

1. The probe is inserted into the grain to the bottom of the carrier.
2. After the probe has reached its maximum depth:
   • Compartmentalized probe – after the compartments are opened and closed, the pneumatic recovery system is activated to transfer the sample to the collection box.
   • Core tip – the pneumatic recovery system is activated to transfer the sample to the collection box.
3. Repeat steps 1 and 2 until an appropriate number of samples has been collected. (Section 8.3 – Probe sampling patterns).
4. While drawing the sample, each increment should be checked for uniformity. Based on the quality and quantity of the samples taken, determine if additional probes are required.
5. Reduce the sample to the appropriate size.
   • * If a moisture test is required, place the sample or a 300-gram portion of the sample in an airtight container with proper identification.
   • ** A Boerner-type divider must be used to reduce “official samples”.
6. Complete a Sample Record and Information Slip (Form I-120) and include it with the sample.

8.8 Point type and strip type automated sampling

Samples taken by either point type or strip type sampling systems are only eligible for a CGC Submitted Sample Certificate Type 2 regardless of the overseeing authority.

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