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APPENDIX 7 CRUDE DRUGS

7.1 SAMPLING

         Sampling of material in bulk​

         Unless otherwise specified, the sample should be taken by the following methods, and, if necessary, preserved in tightly closed containers.

         1. Examine the uniformity and the integrity of the containers (or of the outer wrapping), the markings and the labelling in the whole batch.

         2. If on external examination the batch is considered as homogeneous, take individual samples from the number of packages as indicated in the following table.

Schedule Recommended for Sampling

         3. From each container or package selected, take three original samples, taking care to avoid fragmentation. Samples should be taken from the top, middle and bottom of the container. In the case of sacks and packages, the three samples should be taken by hand, the first from a depth of not less than 10 cm from the top and the second and third from the middle and bottom after cutting into the side of the package. Samples of seeds should be withdrawn with a grain probe. Material in boxes should first be sampled from the upper layer; then approximately half of the contents should be removed and a second sample taken. Finally after further removal of material, another sample should be taken from the bottom. Samples should be as uniform as possible in mass. The three original samples should then be combined into a pooled sample which should be mixed carefully.

         The average sample is obtained by quartering. From the pooled sample, adequately mixed, into an even and square-shaped heap, and divide it diagonally into four equal parts. Take two diagonally opposite parts and mix carefully. Repeat the process as necessary until the required quantity, to within ±10 per cent, is obtained. Any remaining material should be returned to the batch.

         Using the same quartering procedure, divide the average sample into four final samples, taking care that each portion is representative of the bulk material.

         Sampling of material in retail packages

         From each wholesale container (boxes, cartons, etc.) selected for sampling, take at random two consumer packages. From small batches (1 to 5 boxes), take ten consumer packages. Prepare the pooled sample by mixing the contents of the selected consumer packages and proceed as described above to obtain the final sample.