Sampling stored bulk free-flowing powders

3 Sampling stored bulk free-flowing powders 

It is practically impossible to sample representatively, stationary free-flowing powder because of the severe segregation that has almost certainly occurred. There is only one sound piece of advice to give regarding sampling such material. 

Number of containers in lot Number of containers to be sampled Number of containers in lot Number of containers to be sampled 

For every additional 100 containers one additional container shall be sampled. 

Suppose an analysis is required from several tons of material that is available in bags or small containers. Should a bag be selected at random with the hope that it is representative of the bulk Having selected the bag how should a sample be withdrawn for subsequent analysis  

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